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Plastics materials and its applications-I
Unit-I (Natural polymers)
How a polymer is formed?
Polymers are formed by chemical reactions in which a large number of molecules called monomers are joined sequentially, forming a chain. In many polymers, only one monomer is used. In others, two or three different monomers may be combined.
When many molecules of a simple compound join together, the product is termed a polymer and the process polymerization. The simple compounds whose molecules join together to form the polymers are called monomers. The polymer is a chain of atoms, providing a backbone, to which atoms or groups of atoms are joined.
What elements are plastic made of?
The carbon atom can link to other atoms with up to four chemical bonds. When all of the bonds are to other carbon atoms, diamonds or graphite or carbon black soot may result. For plastics the carbon atoms are also connected to the aforementioned hydrogen, oxygen, nitrogen, chlorine, or sulfur.
What are polymers and what are they made of?
polymer, any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, that are multiples of simpler chemical units called monomers. Polymers make up many of the materials in living organisms, including, for example, proteins, cellulose, and nucleic acids.
Shellac Resin
Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes and dissolved in ethanol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and it seals out moisture.
Production of shellac
Shellac is scraped from the bark of the trees where the female lac bug also known as Laccifer lacca, secretes it to form a tunnel-like tube as it traverses the branches of the tree. Though these tunnels are sometimes referred to as "cocoons", they are not literally cocoons in the entomological sense. This insect is in the same Superfamily as the insect from which cochineal is obtained. The insects suck the sap of the tree and excrete "sticklac" almost constantly. The least coloured shellac is produced when the insects feed on the kusum tree (Schleichera).
The number of lac bugs required to produce 1 kilogram (2.2 lb) of shellac has variously been estimated as 50000, 200000 or 300000. The root word lakh is a South Asian unit for 100,000 and presumably refers to the huge numbers of insects that swarm on host trees, up to 150 per square inch.
The raw shellac, which contains bark shavings and lac bugs removed during scraping, is placed in canvas tubes (much like long socks) and heated over a fire. This causes the shellac to liquify, and it seeps out of the canvas, leaving the bark and bugs behind. The thick, sticky shellac is then dried into a flat sheet and broken into flakes, or dried into "buttons" (pucks/cakes), then bagged and sold. The end-user then crushes it into a fine powder and mixes it with ethyl alcohol prior to use, to dissolve the flakes and make liquid shellac.
Liquid shellac has a limited shelf life (about 1 year), hence it is sold in dry form for dissolution prior to use. Liquid shellac sold in hardware stores is clearly marked with the production (mixing) date, so the consumer can know whether the shellac inside is still good. Alternatively, old shellac may be tested to see if it is still usable: a few drops on glass should quickly dry to a hard surface. Shellac that remains tacky for a long time is no longer usable. Storage life depends on peak temperature, so refrigeration extends shelf life.
The thickness (concentration) of shellac is measured by the unit "pound cut", referring to the amount (in pounds) of shellac flakes dissolved in a gallon of denatured alcohol. For example: a 1-lb. cut of shellac is the strength obtained by dissolving one pound of shellac flakes in a gallon of alcohol. Most pre-mixed commercial preparations come at a 3-lb. cut. Multiple thin layers of shellac produce a significantly better end result than a few thick layers. Thick layers of shellac do not adhere to the substrate or to each other well, and thus can peel off with relative ease; in addition, thick shellac will obscure fine details in carved designs in wood and other substrates.
Shellac naturally dries to a high-gloss sheen. For applications where a flatter (less shiny) sheen is desired, products containing amorphous silica, such as "Shellac Flat," may be added to the dissolved shellac.
Shellac naturally contains a small amount of wax (3%-5% by volume), which comes from the lac bug. In some preparations, this wax is removed (the resulting product being called "dewaxed shellac"). This is done for applications where the shellac will be coated with something else (such as paint or varnish), so the topcoat will adhere. Waxy (non-dewaxed) shellac appears milky in liquid form, but dries clear.
Application of shellac......
Sheets of Braille were coated with shellac to help protect them from wear due to being read by hand.
Shellac was used from the mid-19th century to produce small moulded goods such as picture frames, boxes, toilet articles, jewelry, inkwells and even dentures. Advances in plastics have rendered shellac obsolete as a moulding compound.
Shellac was once used for fixing inductor, motor, generator and transformer windings, where it was applied directly to single layer windings in an alcohol solution. For multilayer windings, the whole coil was submerged in shellac solution, then drained and placed in a warm place to allow the alcohol to evaporate. The shellac then locks the wire turns in place, provides extra insulation and prevents movement and vibration, reducing buzz and hum. In motors and generators it also helps transfer force generated by magnetic attraction and repulsion from the windings to the rotor or armature. In more recent times, synthetic resins, such as glyptol, (Glyptal), have been substituted for the shellac. Some applications use shellac mixed with other natural or synthetic resins, such as pine resin or phenol-formaldehyde resin, of which Bakelite is the best known, for electrical use. Mixed with other resins, barium sulfate, calcium carbonate, zinc sulfide, aluminium oxide and/or cuprous carbonate (malachite), shellac forms a component of heat-cured capping cement used to fasten the caps or bases to the bulbs of electric lamps.
Natural rubber
Natural rubber consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds plus water. Malaysia is a leading producer of rubber. Forms of polyisoprene that are used as natural rubbers are classified as elastomers. Natural rubber is used by many manufacturing companies for the production of rubber products. Currently, rubber is harvested mainly in the form of the latex from certain trees. The latex is a sticky, milky colloid drawn off by making incisions into the bark and collecting the fluid in vessels in a process called "tapping". The latex then is refined into rubber ready for commercial processing. Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and high resilience, and is extremely waterproof
Application of natural rubber-
It is used for cements; for adhesive, insulating, and friction tapes; and for crepe rubber used in insulating blankets and footwear. vehicle tires and conveyor belts,hose, tires, and rollers,various kinds of shock absorbers and for specialized machinery mountings designed to reduce vibration,air hoses, balloons, balls, and cushions.
The resistance of rubber to water and to the action of most fluid chemicals has led to its use in rainwear, diving gear, and chemical and medicinal tubing, and as a lining for storage tanks, processing equipment, and railroad tank cars. Because of their electrical resistance, soft rubber goods are used as insulation and for protective gloves, shoes, and blankets; hard rubber is used for articles such as telephone housings, parts for radio sets, meters, and other electrical instruments. The coefficient of friction of rubber, which is high on dry surfaces and low on wet surfaces, leads to the use of rubber both for power-transmission belting and for water-lubricated bearings in deep-well pumps.
Properties.....
Current sources
Rubber is generally cultivated in large plantations. The bulk of the rubber produced is of the synthetic variety, which is derived from petroleum, the price of natural rubber is determined, to a large extent, by the prevailing global price of crude oil. Today, Asia is the main source of natural rubber, accounting for about 94% of output in 2005. The three largest producing countries, Thailand, Indonesia and Malaysia, together account for around 72% of all natural rubber production. Natural rubber is not cultivated widely in its native continent of South America due to the existence of South American leaf blight, and other natural predators of the rubber tree.
Vulcanization
Vulcanization Natural rubber is often vulcanized, a process by which the rubber is heated and sulfur, peroxide or bisphenol are added to improve resistance and elasticity, and to prevent it from perishing. The development of vulcanization is most closely associated with Charles Goodyear in 1839. Before World War II era manufacturing, carbon black was often used as an additive to rubber to improve its strength, especially in vehicle tires.
Casein
Casein ( from Latin caseus, "cheese") is the name for a family of related phosphoproteins. These proteins are commonly found in mammalian milk, making up 80% of the proteins in cow milk and between 20% and 45% of the proteins in human milk. Casein has a wide variety of uses, from being a major component of cheese, to use as a food additive, to a binder for safety matches. As a food source, casein supplies amino acids, carbohydrates, and the two inorganic elements calcium and phosphorus
Uses
Polymers are formed by chemical reactions in which a large number of molecules called monomers are joined sequentially, forming a chain. In many polymers, only one monomer is used. In others, two or three different monomers may be combined.
When many molecules of a simple compound join together, the product is termed a polymer and the process polymerization. The simple compounds whose molecules join together to form the polymers are called monomers. The polymer is a chain of atoms, providing a backbone, to which atoms or groups of atoms are joined.
What elements are plastic made of?
The carbon atom can link to other atoms with up to four chemical bonds. When all of the bonds are to other carbon atoms, diamonds or graphite or carbon black soot may result. For plastics the carbon atoms are also connected to the aforementioned hydrogen, oxygen, nitrogen, chlorine, or sulfur.
What are polymers and what are they made of?
polymer, any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, that are multiples of simpler chemical units called monomers. Polymers make up many of the materials in living organisms, including, for example, proteins, cellulose, and nucleic acids.
Shellac Resin
Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes and dissolved in ethanol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and it seals out moisture.
Production of shellac
Shellac is scraped from the bark of the trees where the female lac bug also known as Laccifer lacca, secretes it to form a tunnel-like tube as it traverses the branches of the tree. Though these tunnels are sometimes referred to as "cocoons", they are not literally cocoons in the entomological sense. This insect is in the same Superfamily as the insect from which cochineal is obtained. The insects suck the sap of the tree and excrete "sticklac" almost constantly. The least coloured shellac is produced when the insects feed on the kusum tree (Schleichera).
The number of lac bugs required to produce 1 kilogram (2.2 lb) of shellac has variously been estimated as 50000, 200000 or 300000. The root word lakh is a South Asian unit for 100,000 and presumably refers to the huge numbers of insects that swarm on host trees, up to 150 per square inch.
The raw shellac, which contains bark shavings and lac bugs removed during scraping, is placed in canvas tubes (much like long socks) and heated over a fire. This causes the shellac to liquify, and it seeps out of the canvas, leaving the bark and bugs behind. The thick, sticky shellac is then dried into a flat sheet and broken into flakes, or dried into "buttons" (pucks/cakes), then bagged and sold. The end-user then crushes it into a fine powder and mixes it with ethyl alcohol prior to use, to dissolve the flakes and make liquid shellac.
Liquid shellac has a limited shelf life (about 1 year), hence it is sold in dry form for dissolution prior to use. Liquid shellac sold in hardware stores is clearly marked with the production (mixing) date, so the consumer can know whether the shellac inside is still good. Alternatively, old shellac may be tested to see if it is still usable: a few drops on glass should quickly dry to a hard surface. Shellac that remains tacky for a long time is no longer usable. Storage life depends on peak temperature, so refrigeration extends shelf life.
The thickness (concentration) of shellac is measured by the unit "pound cut", referring to the amount (in pounds) of shellac flakes dissolved in a gallon of denatured alcohol. For example: a 1-lb. cut of shellac is the strength obtained by dissolving one pound of shellac flakes in a gallon of alcohol. Most pre-mixed commercial preparations come at a 3-lb. cut. Multiple thin layers of shellac produce a significantly better end result than a few thick layers. Thick layers of shellac do not adhere to the substrate or to each other well, and thus can peel off with relative ease; in addition, thick shellac will obscure fine details in carved designs in wood and other substrates.
Shellac naturally dries to a high-gloss sheen. For applications where a flatter (less shiny) sheen is desired, products containing amorphous silica, such as "Shellac Flat," may be added to the dissolved shellac.
Shellac naturally contains a small amount of wax (3%-5% by volume), which comes from the lac bug. In some preparations, this wax is removed (the resulting product being called "dewaxed shellac"). This is done for applications where the shellac will be coated with something else (such as paint or varnish), so the topcoat will adhere. Waxy (non-dewaxed) shellac appears milky in liquid form, but dries clear.
Application of shellac......
Sheets of Braille were coated with shellac to help protect them from wear due to being read by hand.
Shellac was used from the mid-19th century to produce small moulded goods such as picture frames, boxes, toilet articles, jewelry, inkwells and even dentures. Advances in plastics have rendered shellac obsolete as a moulding compound.
Shellac was once used for fixing inductor, motor, generator and transformer windings, where it was applied directly to single layer windings in an alcohol solution. For multilayer windings, the whole coil was submerged in shellac solution, then drained and placed in a warm place to allow the alcohol to evaporate. The shellac then locks the wire turns in place, provides extra insulation and prevents movement and vibration, reducing buzz and hum. In motors and generators it also helps transfer force generated by magnetic attraction and repulsion from the windings to the rotor or armature. In more recent times, synthetic resins, such as glyptol, (Glyptal), have been substituted for the shellac. Some applications use shellac mixed with other natural or synthetic resins, such as pine resin or phenol-formaldehyde resin, of which Bakelite is the best known, for electrical use. Mixed with other resins, barium sulfate, calcium carbonate, zinc sulfide, aluminium oxide and/or cuprous carbonate (malachite), shellac forms a component of heat-cured capping cement used to fasten the caps or bases to the bulbs of electric lamps.
Natural rubber
Natural rubber consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds plus water. Malaysia is a leading producer of rubber. Forms of polyisoprene that are used as natural rubbers are classified as elastomers. Natural rubber is used by many manufacturing companies for the production of rubber products. Currently, rubber is harvested mainly in the form of the latex from certain trees. The latex is a sticky, milky colloid drawn off by making incisions into the bark and collecting the fluid in vessels in a process called "tapping". The latex then is refined into rubber ready for commercial processing. Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and high resilience, and is extremely waterproof
Application of natural rubber-
It is used for cements; for adhesive, insulating, and friction tapes; and for crepe rubber used in insulating blankets and footwear. vehicle tires and conveyor belts,hose, tires, and rollers,various kinds of shock absorbers and for specialized machinery mountings designed to reduce vibration,air hoses, balloons, balls, and cushions.
The resistance of rubber to water and to the action of most fluid chemicals has led to its use in rainwear, diving gear, and chemical and medicinal tubing, and as a lining for storage tanks, processing equipment, and railroad tank cars. Because of their electrical resistance, soft rubber goods are used as insulation and for protective gloves, shoes, and blankets; hard rubber is used for articles such as telephone housings, parts for radio sets, meters, and other electrical instruments. The coefficient of friction of rubber, which is high on dry surfaces and low on wet surfaces, leads to the use of rubber both for power-transmission belting and for water-lubricated bearings in deep-well pumps.
Properties.....
- Rubber latex Rubber exhibits unique physical and chemical properties. Rubber's stress-strain behavior exhibits the Mullins effect and the Payne effect, and is often modeled as hyperelastic. Rubber strain crystallizes.
- Due to the presence of a double bond in each repeat unit, natural rubber is susceptible to vulcanisation and sensitive to ozone cracking. The two main solvents for rubber are turpentine and naphtha (petroleum). The former has been in use since 1764 when François Fresnau made the discovery. Giovanni Fabbroni is credited with the discovery of naphtha as a rubber solvent in 1779. Because rubber does not dissolve easily, the material is finely divided by shredding prior to its immersion.
- An ammonia solution can be used to prevent the coagulation of raw latex while it is being transported from its collection
Current sources
Rubber is generally cultivated in large plantations. The bulk of the rubber produced is of the synthetic variety, which is derived from petroleum, the price of natural rubber is determined, to a large extent, by the prevailing global price of crude oil. Today, Asia is the main source of natural rubber, accounting for about 94% of output in 2005. The three largest producing countries, Thailand, Indonesia and Malaysia, together account for around 72% of all natural rubber production. Natural rubber is not cultivated widely in its native continent of South America due to the existence of South American leaf blight, and other natural predators of the rubber tree.
Vulcanization
Vulcanization Natural rubber is often vulcanized, a process by which the rubber is heated and sulfur, peroxide or bisphenol are added to improve resistance and elasticity, and to prevent it from perishing. The development of vulcanization is most closely associated with Charles Goodyear in 1839. Before World War II era manufacturing, carbon black was often used as an additive to rubber to improve its strength, especially in vehicle tires.
Casein
Casein ( from Latin caseus, "cheese") is the name for a family of related phosphoproteins. These proteins are commonly found in mammalian milk, making up 80% of the proteins in cow milk and between 20% and 45% of the proteins in human milk. Casein has a wide variety of uses, from being a major component of cheese, to use as a food additive, to a binder for safety matches. As a food source, casein supplies amino acids, carbohydrates, and the two inorganic elements calcium and phosphorus
Uses
- Paint- Casein preparation in an old etching operation in Müllheim Casein paint is a fast-drying, water-soluble medium used by artists. Casein paint has been used since ancient Egyptian times as a form of tempera paint,with the advent of acrylic paint, casein became less popular. It is still widely used by scene painters, although acrylic has made inroads in that field as well.
- Glue- Casein-based glues, formulated from casein, water, hydrated lime and sodium hydroxide were popular for woodworking, including for aircraft, as late as the de Havilland Albatross airliner. Casein glue is also used in transformer manufacturing (specifically transformer board) due to its oil permeability. While largely replaced by synthetic resins,
- Cheesemaking- Cheesemaking Cheese consists of proteins and fat from milk, usually the milk of cows, buffalo, goats, or sheep. It is produced by coagulation of casein. Typically, the milk is acidified and then coagulated by the addition of rennet, containing a proteolytic enzyme, typically obtained from the stomachs of calves. The solids are separated and pressed into final form.
- Unlike many proteins, casein is not coagulated by heat. During the process of clotting, milk-clotting proteases act on the soluble portion of the caseins, κ-casein, thus originating an unstable micellar state that results in clot formation.
- Plastics and fiber/fibre Some of the earliest plastics were based on casein. In particular, galalith was well known for use in buttons.
- Protein supplements An attractive property of the casein molecule is its ability to form a gel or clot in the stomach, which makes it very efficient in nutrient supply. The clot is able to provide a sustained slow release of amino acids into the blood stream,
- Medical and dental uses Casein-derived compounds are used in tooth remineralization products to stabilize amorphous calcium phosphate (ACP) and release the ACP onto tooth surfaces, where it can facilitate remineralization.
Unit-II (Commodity plastics- Olefins & Styrene plastics)
Application of plastics
Uses of plastics in Agriculture-
A wide range of plastics are used in agriculture, including, polyolefin, polyethylene (PE), Polypropylene (PP), Ethylene-Vinyl Accetate Copolymer (EVA), Poly-vinyl chloride (PVC) and, in less frequently, Polycarbonate (PC) and poly-methyl-methacrylate (PMMA)
Greenhouses:
Greenhouses are like intensive-care units. Thanks to them, plants are exposed to the sunlight and can grow in ideal conditions according to their physiological properties. The use of greenhouses indeed provides farmers with the possibility to create the appropriate environmental conditions that plants require for faster and safer growth, to avoid extreme temperatures and protect crops from harmful external conditions.
Tunnels:
Tunnels have the same features as greenhouses, except for their complexity and their height. Crops that are the most commonly cultivated in tunnels are asparagus, watermelon, etc.
Mulching:
Mulching or covering the ground with plastic film helps maintain humidity as evaporation is reduced. It also improves thermal conditions for the plant’s roots, avoids contact between the plant and the ground and prevents weed from growing and competing with for water and nutrients.
Plastic reservoirs and irrigation systems:
When combined, plastic reservoirs and plastic irrigation systems make an essential contribution to water management. Water can be stored in dams covered with plastics materials to avoid leaking and distributed via pipes, drop irrigation systems and systems for water circulation.
Silage:
This application, which was developed to store animals’ grains and straw during the winter, is another proof of the value of plastics. Plastic films used to store silage are resistant and the content canbe stored for years.
Other plastic applications include boxes;
crates for crop collecting, handling and transport; components for irrigation systems like fittings and spray cones; tapes that help hold the aerial parts of the plants in the greenhouses, or even nets to shade the interior of the greenhouses or reduce the effects of hail
Application of plastics in Packaging__
Food packaging
Lamination
Wrapers
Packaging of electrical and electronic parts
Water & milk packaging
Application of plastics in building__
Application of plastics in transport.......
Automotive
More plastics, by volume, than steel are now used in today's cars for a myriad of components. At the end of a vehicle's working life, plastics components can be recycled or the energy can be recovered through incineration Plastics versatility aids the automotive industry in meeting ever more stringent requirements in terms of economical performance, safety, comfort and environmental considerations
Aerospace
The aerodynamic requirements of aerospace products demand maximum design flexibility and minimal weight. Plastics can be formulated to meet a wide variety of specifications and are ideal for components incorporating smooth curves. Composites are widely used in the panels of military jets and helicopters as well as for wing skins, nacelles, fairings, flaps and helicopter rotor-blades in commercial applications. Plastics are also found throughout aircraft interiors in, for example, bulkheads, galleys, stair units, seating and flooring.
Rail
Materials used in railway locomotives, carriages and other rolling stock have to withstand wear and tear from heavy use. The durability of plastics is one of the factors making them the first choice for engine and carriage panels, flooring, luggage racks, seating and doors.
Marine
Plastics' ability to withstand a harsh marine environment makes them essential in all types of marine craft, from ocean liners to sailing dinghies. Plastics do not corrode or warp and need less maintenance than other traditional materials to remain attractive and in good working condition.
Application of plastics in electrical-electronics & telecommunication ___
MCB
IC
Circuits
Cabinets
Display
Optical fiber
Current carrying springs & relays
Micro-motors
Remote
Camera
LCDs
Application of plastics in Medical…………..
Medicine packaging
Artificial body parts like hand,legs,heart
Contact lenses
Blood bags
Injection
Stretcher
X-ray
Surgical tools
Surgery
Application of plastics in Furniture__
Chair, Tables, shower heads, dishes, skylights, eye glasses, cameras, floor waxes, carpets, piano keys, switch cover plates, buttons, door knobs, papers, shoe heels, toothbrush handles, pen and pencil barrels, beads, toys, fisherperson's floats and tackle, cutlery handles, combs, washing machines, detergent dispensers, salad bowls, ash trays, croquet balls, water hose nozzels, football helmets, inks, clothing, rainwear, cellophane, wash tubs, luggage, costume jewlery, beverage cases, trash-can liners, produce bags, canteens, synthetic leather, refrigerator insulation, sponges, furniture cushioning, model airplane and car kits, place mats, envelope windows, ice buckets, egg cartons, shower curtains
Application of plastics in automobiles __
Application of plastics in aerospace...
Plastics offer a number of advantages for the aerospace industry when compared with other materials, such as metals and ceramics. One important advantage of plastics is their low specific gravity. A typical plastic will have half the density of aluminum and one-sixth (1/6) the density of steel. When fillers such as glass or carbon fibers are used, plastics can achieve relatively high modulus (stiffness), and the combination of high stiffness and light weight results in a high specific modulus. This is beneficial for aerospace applications because low weight tends to result in fuel efficiency.
Uses of plastics in Agriculture-
A wide range of plastics are used in agriculture, including, polyolefin, polyethylene (PE), Polypropylene (PP), Ethylene-Vinyl Accetate Copolymer (EVA), Poly-vinyl chloride (PVC) and, in less frequently, Polycarbonate (PC) and poly-methyl-methacrylate (PMMA)
Greenhouses:
Greenhouses are like intensive-care units. Thanks to them, plants are exposed to the sunlight and can grow in ideal conditions according to their physiological properties. The use of greenhouses indeed provides farmers with the possibility to create the appropriate environmental conditions that plants require for faster and safer growth, to avoid extreme temperatures and protect crops from harmful external conditions.
Tunnels:
Tunnels have the same features as greenhouses, except for their complexity and their height. Crops that are the most commonly cultivated in tunnels are asparagus, watermelon, etc.
Mulching:
Mulching or covering the ground with plastic film helps maintain humidity as evaporation is reduced. It also improves thermal conditions for the plant’s roots, avoids contact between the plant and the ground and prevents weed from growing and competing with for water and nutrients.
Plastic reservoirs and irrigation systems:
When combined, plastic reservoirs and plastic irrigation systems make an essential contribution to water management. Water can be stored in dams covered with plastics materials to avoid leaking and distributed via pipes, drop irrigation systems and systems for water circulation.
Silage:
This application, which was developed to store animals’ grains and straw during the winter, is another proof of the value of plastics. Plastic films used to store silage are resistant and the content canbe stored for years.
Other plastic applications include boxes;
crates for crop collecting, handling and transport; components for irrigation systems like fittings and spray cones; tapes that help hold the aerial parts of the plants in the greenhouses, or even nets to shade the interior of the greenhouses or reduce the effects of hail
Application of plastics in Packaging__
Food packaging
Lamination
Wrapers
Packaging of electrical and electronic parts
Water & milk packaging
Application of plastics in building__
- Flooring
- Roofing
- Insulation
- Wall
- Pipes
- Windows
- Doors
- Pipes : Electrical Conduits, Rain Water & Sewage pipes, Plumbing, Gas Distributions.
- Cables : PVC Insulation on cables, Insulation Tapes .
- Flooring : Flooring tiles & Rolls .
- Domes / sky lights : Opaque as well as transparent.
- Roofing : Coloured or Double skinned for insulation.
- Windows & doors : Extruded sections for Door and windows and panels.
- Storage tanks : Storage tanks.
- Hardware accessories : Washers, Nut bolts, Sleeves, Anchoring wires.
- Temporary structures: Guard cabins, tents
- Insulation materials: PVC sheets, insulating membranes.
Application of plastics in transport.......
Automotive
More plastics, by volume, than steel are now used in today's cars for a myriad of components. At the end of a vehicle's working life, plastics components can be recycled or the energy can be recovered through incineration Plastics versatility aids the automotive industry in meeting ever more stringent requirements in terms of economical performance, safety, comfort and environmental considerations
Aerospace
The aerodynamic requirements of aerospace products demand maximum design flexibility and minimal weight. Plastics can be formulated to meet a wide variety of specifications and are ideal for components incorporating smooth curves. Composites are widely used in the panels of military jets and helicopters as well as for wing skins, nacelles, fairings, flaps and helicopter rotor-blades in commercial applications. Plastics are also found throughout aircraft interiors in, for example, bulkheads, galleys, stair units, seating and flooring.
Rail
Materials used in railway locomotives, carriages and other rolling stock have to withstand wear and tear from heavy use. The durability of plastics is one of the factors making them the first choice for engine and carriage panels, flooring, luggage racks, seating and doors.
Marine
Plastics' ability to withstand a harsh marine environment makes them essential in all types of marine craft, from ocean liners to sailing dinghies. Plastics do not corrode or warp and need less maintenance than other traditional materials to remain attractive and in good working condition.
Application of plastics in electrical-electronics & telecommunication ___
MCB
IC
Circuits
Cabinets
Display
Optical fiber
Current carrying springs & relays
Micro-motors
Remote
Camera
LCDs
Application of plastics in Medical…………..
Medicine packaging
Artificial body parts like hand,legs,heart
Contact lenses
Blood bags
Injection
Stretcher
X-ray
Surgical tools
Surgery
Application of plastics in Furniture__
Chair, Tables, shower heads, dishes, skylights, eye glasses, cameras, floor waxes, carpets, piano keys, switch cover plates, buttons, door knobs, papers, shoe heels, toothbrush handles, pen and pencil barrels, beads, toys, fisherperson's floats and tackle, cutlery handles, combs, washing machines, detergent dispensers, salad bowls, ash trays, croquet balls, water hose nozzels, football helmets, inks, clothing, rainwear, cellophane, wash tubs, luggage, costume jewlery, beverage cases, trash-can liners, produce bags, canteens, synthetic leather, refrigerator insulation, sponges, furniture cushioning, model airplane and car kits, place mats, envelope windows, ice buckets, egg cartons, shower curtains
Application of plastics in automobiles __
- dashboard
- Seat
- steering wheel
- roof, after Wai
- engine cover and floor mats
- Bumper
- pedal
- radiator grille
- fender
- Inlet
- deflector Light
- Class
- fender
- Inlet
- deflector
- Light Class
Application of plastics in aerospace...
Plastics offer a number of advantages for the aerospace industry when compared with other materials, such as metals and ceramics. One important advantage of plastics is their low specific gravity. A typical plastic will have half the density of aluminum and one-sixth (1/6) the density of steel. When fillers such as glass or carbon fibers are used, plastics can achieve relatively high modulus (stiffness), and the combination of high stiffness and light weight results in a high specific modulus. This is beneficial for aerospace applications because low weight tends to result in fuel efficiency.
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Unit-III (Commodity plastics- Vinyl & Cellulosic plastics)
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Unit-IV (Engineering plastics)
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Plastics processing technology - I
Unit-I (Introduction)
1._introduction_to_plastics_processing..ppt | |
File Size: | 825 kb |
File Type: | ppt |
Q. Why we use plastics?
Ans- These are the following properties, that's why we use plastics...
Ans- These are the following properties, that's why we use plastics...
- Light weight
- Electrical insulation
- Pleasant to touch
- Freedom of color & design
- Low temperature melting capacity
- Electroplating
- Transparency
- Chemical & water resistance
- Hygienic and non Allergic
- Non resistance to heat and sun light
Unit-II (Injection moulding process)
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Unit-III (Extrusion)
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Unit-IV (Blow moulding)
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Unit-V (Automation)
automated_material_handling_systems.ppt | |
File Size: | 1178 kb |
File Type: | ppt |
Fundamental of plastics product and mould design
Unit-I (Engineering drawing concepts)
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Unit-II (Product design)
plastic_product_design..ppt | |
File Size: | 1067 kb |
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Unit-III
Injection mould design
injection_mould_design..ppt | |
File Size: | 4357 kb |
File Type: | ppt |
Split moulds
types_of_moulds-split_mould.ppt | |
File Size: | 714 kb |
File Type: | ppt |
Unit-IV
Blow mould design
blow_mould_design..ppt | |
File Size: | 1404 kb |
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Compression mould design
compression_mould..ppt | |
File Size: | 217 kb |
File Type: | ppt |
Plastics testing technique-I
Unit-I (Concept of testing & Identification of plastics)
The following are some of the major reasons for testing:
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Unit-II (Material characterization)
material_charecterization..ppt | |
File Size: | 516 kb |
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Unit-III (Mechanical properties)
3.mechanical_properties..ppt | |
File Size: | 1177 kb |
File Type: | ppt |
Unit-IV (Thermal properties)
Fundamental of polymer science
thermal_properties..ppt | |
File Size: | 7988 kb |
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Unit-I (Introduction to polymer science)
introduction_to_polymer_science.pdf | |
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polymer_science_and_fundamental..ppt | |
File Size: | 1987 kb |
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Unit-II (Polymerization)
polymerization..pdf | |
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Unit-III
thermal_transition..pdf | |
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Unit-IV (Polymer characterization)
polymer_science__book_..pdf | |
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Additives and compounding
Unit-I (Introduction to Additives)
Q. What is additives?
Ans- Additives are substances that are added in a polymer to modify its properties. (Plastic Additives)
Classification of plastic additives
Plastic additives is an important and indispensable raw materials of plastic products, there many kinds of plastic additives. Now, let's introduce the classification of plastic additives.
The most common plastic additives includes heat and light stabilizer, antioxidant, antistatic additives, lubricant, fire retardant, and plasticizers and impact modifiers, etc. The other special additives, includes an anti caking and anti smoke agent, foaming agent, antimicrobial agent, and clarify and nucleating agent..
Ans- Additives are substances that are added in a polymer to modify its properties. (Plastic Additives)
Classification of plastic additives
Plastic additives is an important and indispensable raw materials of plastic products, there many kinds of plastic additives. Now, let's introduce the classification of plastic additives.
The most common plastic additives includes heat and light stabilizer, antioxidant, antistatic additives, lubricant, fire retardant, and plasticizers and impact modifiers, etc. The other special additives, includes an anti caking and anti smoke agent, foaming agent, antimicrobial agent, and clarify and nucleating agent..
Unit-II (Additives)
additives.ppt | |
File Size: | 222 kb |
File Type: | ppt |
Natural fiber
Natural fibers can be defined as substances produced by plants and animals that can be spun into filament, thread or rope and in a next step be woven, knitted, matted or bound.
Cellulose
Cellulose is an organic compound with the formula (C6H10O5)n, a polysaccharide consisting of a linear chain of several hundred to many thousands. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth.
The cellulose content of cotton fiber is 90%, that of wood is 40–50% and that of dried hemp is approximately 45%.
Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Cellulose for industrial use is mainly obtained from wood pulp and cotton.Structure and properties
Cellulose has no taste, is odorless, is hydrophilic with the contact angle of 20–30, is insoluble in water and most organic solvents, is chiral and is biodegradable. It can be broken down chemically into its glucose units by treating it with concentrated acids at high temperature.
Cellulose is a straight chain polymer: unlike starch, no coiling or branching occurs, and the molecule adopts an extended and rather stiff rod-like conformation, aided by the equatorial conformation of the glucose residues. The multiple hydroxyl groups on the glucose from one chain form hydrogen bonds with oxygen atoms on the same or on a neighbor chain, holding the chains firmly together side-by-side and forming microfibrils with high tensile strength. This confers tensile strength in cell walls, where cellulose microfibrils are meshed into a polysaccharide matrix.
Cotton fibres represent the purest natural form of cellulose, containing more than 90% of this polysaccharide.Compared to starch, cellulose is also much more crystalline. Whereas starch undergoes a crystalline to amorphous transition when heated beyond 60–70 °C in water (as in cooking), cellulose requires a temperature of 320 °C and pressure of 25 MPa to become amorphous in water.
Many properties of cellulose depend on its chain length or degree of polymerization, the number of glucose units that make up one polymer molecule. Cellulose from wood pulp has typical chain lengths between 300 and 1700 units; cotton and other plant fibers as well as bacterial cellulose have chain lengths ranging from 800 to 10,000 units. Molecules with very small chain length resulting from the breakdown of cellulose are known as cellodextrins; in contrast to long-chain cellulose, cellodextrins are typically soluble in water and organic solvents.
Cellulose is soluble in Schweizer's reagent, cupriethylenediamine (CED), cadmiumethylenediamine (Cadoxen), N-methylmorpholine N-oxide, and lithium chloride / dimethylacetamide.[16] This is used in the production of regenerated celluloses (such as viscose and cellophane) from dissolving pulp. Cellulose is also soluble in many kinds of ionic liquids.
Cellulose consists of crystalline and amorphous regions. By treating it with strong acid, the amorphous regions can be broken up, thereby producing nanocrystalline cellulose, a novel material with many desirable properties. Recently, nanocrystalline cellulose was used as the filler phase in bio-based polymer matrices to produce nanocomposites with superior thermal and mechanical properties
Applications
A strand of cellulose (conformation Iα), showing the hydrogen bonds (dashed) within and between cellulose molecules.
Cellulose for industrial use is mainly obtained from wood pulp and cotton.[6] The kraft process is used to separate cellulose from lignin, another major component of plant matter.
Jute
Jute" is the name of the plant or fiber that is used to make burlap, Hessian or gunny cloth. Jute is one of the most affordable natural fibers and is second only to cotton in amount produced and variety of uses of vegetable fibers.
Jute fibers are composed primarily of the plant materials cellulose and lignin. It falls into the bast fibre category (fiber collected from bast, the phloem of the plant, sometimes called the "skin") along with kenaf, industrial hemp, flax (linen), ramie, etc.
The industrial term for jute fiber is raw jute. The fibers are off-white to brown, and 1–4 metres (3–13 feet) long.
Jute is also called "the golden fiber" for its color and high cash value
Uses
Making twine, rope, and making matting are among its uses.
Together with the sugar can be used to build aeroplane panels.
Jute is in great demand due to its cheapness, softness, length, lustre and uniformity of its fibre. It is also called the 'golden fibre' due to its versatile nature.It is called the 'brown paper bag' as it is also used to store rice, wheat, grains, etc.
Fiber
Jute fabric
Coffee sacks made of jute.
Jute fiber is extracted from retted stem of jute plantsJute matting is used to prevent flood erosion while natural vegetation becomes established. For this purpose, a natural and biodegradable fiber is essential.
Jute is the second most important vegetable fiber after cotton due to its versatility. Jute is used chiefly to make cloth for wrapping bales of raw cotton, and to make sacks and coarse cloth. The fibers are also woven into curtains, chair coverings, carpets, area rugs, hessian cloth, and backing for linoleum.
While jute is being replaced by synthetic materials in many of these uses, some uses take advantage of jute's biodegradable nature, where synthetics would be unsuitable. Examples of such uses include containers for planting young trees, which can be planted directly with the container without disturbing the roots, and land restoration where jute cloth prevents erosion occurring while natural vegetation becomes established.
Jute is regularly used in the production of clothes, particularly sweaters and underwear. Its soft fabric structure is known to be very comfortable to the person wearing it and therefore, popularity for jute clothes has increased significantly over the last decade.[citation needed]
The fibers are used alone or blended with other types of fiber to make twine and rope. Jute butts, the coarse ends of the plants, are used to make inexpensive cloth. Conversely, very fine threads of jute can be separated out and made into imitation silk. As jute fibers are also being used to make pulp and paper, and with increasing concern over forest destruction for the wood pulp used to make most paper, the importance of jute for this purpose may increase. Jute has a long history of use in the sackings, carpets, wrapping fabrics (cotton bale), and construction fabric manufacturing industry.
Traditionally jute was used in traditional textile machineries as textile fibers having cellulose (vegetable fiber content) and lignin (wood fiber content). But, the major breakthrough came when the automobile, pulp and paper, and the furniture and bedding industries started to use jute and its allied fibers with their non-woven and composite technology to manufacture nonwovens, technical textiles, and composites. Therefore, jute has changed its textile fiber outlook and steadily heading towards its newer identity, i.e., wood fiber. As a textile fiber, jute has reached its peak from where there is no hope of progress, but as a wood fiber jute has many promising features.
Jute is used in the manufacture of a number of fabrics such as Hessian cloth, sacking, scrim, carpet backing cloth (CBC), and canvas. Hessian, lighter than sacking, is used for bags, wrappers, wall-coverings, upholstery, and home furnishings. Sacking, a fabric made of heavy jute fibers, has its use in the name. CBC made of jute comes in two types. Primary CBC provides a tufting surface, while secondary CBC is bonded onto the primary backing for an overlay. Jute packaging is used as an eco-friendly substitute.
Diversified jute products are becoming more and more valuable to the consumer today. Among these are espadrilles, soft sweaters and cardigans, floor coverings, home textiles, high performance technical textiles, Geotextiles, composites, and more.
Jute floor coverings consist of woven and tufted and piled carpets. Jute Mats and mattings with 5 / 6 mts width and of continuous length are easily being woven in Southern parts of India, in solid and fancy shades, and in different weaves like, Boucle, Panama, Herringbone, etc. Jute Mats & Rugs are made both through Powerloom & Handloom, in large volume from Kerala, India. The traditional Satranji mat is becoming very popular in home décor. Jute non-wovens and composites can be used for underlay, linoleum substrate, and more.
Jute has many advantages as a home textile, either replacing cotton or blending with it. It is a strong, durable, color and light-fast fiber. Its UV protection, sound and heat insulation, low thermal conduction and anti-static properties make it a wise choice in home décor. Also, fabrics made of jute fibers are carbon-dioxide neutral and naturally decomposable. These properties are also why jute can be used in high performance technical textiles.[7]
Moreover, jute can be grown in 4–6 months with a huge amount of cellulose being produced from the jute hurd (inner woody core or parenchyma of the jute stem) that can meet most of the wood needs of the world. Jute is the major crop among others that is able to protect deforestation by industrialisation.[clarification needed]
Thus, jute is the most environment-friendly fiber starting from the seed to expired fiber, as the expired fibers can be recycled more than once.
Jute is also used to make ghillie suits, which are used as camouflage and resemble grasses or brush.
Another diversified jute product is Geotextiles, which made this agricultural commodity more popular in the agricultural sector. It is a lightly woven fabric made from natural fibers that is used for soil erosion control, seed protection, weed control, and many other agricultural and landscaping uses. The Geotextiles can be used more than a year and the bio-degradable jute Geotextile left to rot on the ground keeps the ground cool and is able to make the land more fertile.
Culinary usesIn Nigeria, leaves of Corchorus olitorius are prepared in sticky soup called ewedu together with ingredients such as sweet potato, dried small fish or shrimp.[16] The leaves are rubbed until foamy or sticky before adding to the soup. Amongst the Yoruba of Nigeria, the leaves are called Ewedu, and in the Hausa-speaking northern Nigeria, the leaves are called turgunuwa or lallo. The jute leaves are cut into shreds and added to the soup which would normally contain other ingredients such as meat and/or fish, pepper, onions, and other spices. Likewise, the Lugbara of Northwestern Uganda eat the leaves as soup, locally called pala bi. Jute is also a totem for Ayivu, one of the Lugbara clans.
In the Philippines, especially in Ilocano-dominated areas, this vegetable, locally known as saluyot, can be mixed with either bitter gourd, bamboo shoots, loofah, or sometimes all of them. These have a slimy and slippery texture.
Jute stalks are being dehydrated under the sun, later they will be used as fuel.Diversified byproducts from jute can be used in cosmetics, medicine, paints, and other products.
Features
Jute fiber is 100% bio-degradable and recyclable and thus environmentally friendly.
Coir
Coir is a natural fibre extracted from the husk of coconut and used in products such as floor mats, doormats, brushes, mattresses, etc. Coir is the fibrous material found between the hard, internal shell and the outer coat of a coconut. Other uses of brown coir (made from ripe coconut) are in upholstery padding, sacking and horticulture. White coir, harvested from unripe coconuts, is used for making finer brushes, string, rope and fishing netsCoir fibres are found between the hard, internal shell and the outer coat of a coconut. The individual fibre cells are narrow and hollow, with thick walls made of cellulose. They are pale when immature, but later become hardened and yellowed as a layer of lignin is deposited on their walls. Each cell is about 1 mm (0.04 in) long and 10 to 20 µm (0.0004 to 0.0008 in) in diameter. Fibres are typically 10 to 30 centimetres (4 to 12 in) long.Uses
Red coir is used in floor mats and doormats, brushes, mattresses, floor tiles and sacking. A small amount is also made into twine. Pads of curled brown coir fibre, made by needle-felting (a machine technique that mats the fibres together), are shaped and cut to fill mattresses and for use in erosion control on river banks and hillsides. A major proportion of brown coir pads are sprayed with rubber latex which bonds the fibres together (rubberised coir) to be used as upholstery padding for the automobile industry in Europe. The material is also used for insulation and packaging.
The major use of white coir is in rope manufacture. Mats of woven coir fibre are made from the finer grades of bristle and white fibre using hand or mechanical looms. White coir also is used to make fishing nets due to its strong resistance to saltwater.
In horticulture, coir is a substitute for sphagnum moss because it is free of bacteria and fungal spores. Coir is also useful to deter snails from delicate plantings, and as a growing medium in intensive glasshouse (greenhouse) horticulture.[citation needed]
Coconut coir from Mexico has been found to contain large numbers of colonies of the beneficial fungus Aspergillus terreus, which acts as a biological control against plant pathogenic fungi.
Coir is also used as a substrate to grow mushrooms. The coir is usually mixed with vermiculite and pasteurized with boiling water. After the coir/vermiculite mix has cooled to room temperature, it is placed in a larger container, usually a plastic box. Previously prepared spawn jars are then added, spawn is usually grown in jars using substrates such as rye grains or wild bird seed. This spawn is the mushrooms mycelium and will colonize the coir/vermiculite mix eventually fruiting mushrooms.
Coir is an allergen, as well as the latex and other materials used frequently in the treatment of coir.
Coir can be used as a terrarium substrate for reptiles or arachnids.
Linen
Linen
is a textile made from the fibers of the flax plant, Linum usitatissimum. Linen is laborious to manufacture, but the fiber is very absorbent and garments made of linen are valued for their exceptional coolness and freshness in hot weather.
Many products are made of linen: aprons, bags, towels (swimming, bath, beach, body and wash towels), napkins, bed linens, tablecloths, runners, chair covers, and men's and women's wear.
PropertiesLinen fabric feels cool to the touch. It is smooth, making the finished fabric lint-free, and gets softer the more it is washed.
Linen fabrics have a high natural luster; their natural color ranges between shades of ivory, ecru, tan, or grey. Pure white linen is created by heavy bleaching. Linen fabric typically varies somewhat in thickness and is crisp and textured, but it can in some cases feel stiff and rough, and in other cases feel soft and smooth.
Linen is a very durable, strong fabric, and one of the few that are stronger wet than dry. The fibers do not stretch, and are resistant to damage from abrasion. However, because linen fibers have a very low elasticity, the fabric eventually breaks if it is folded and ironed at the same place repeatedly over time.
Mildew, perspiration, and bleach can also damage the fabric, but it is resistant to moths and carpet beetles. Linen is relatively easy to take care of, since it resists dirt and stains, has no lint or pilling tendency, and can be dry-cleaned, machine-washed or steamed.
Linen should not be dried too much by tumble drying, and it is much easier to iron when damp. Linen wrinkles very easily, and thus some more formal garments require ironing often, in order to maintain perfect smoothness.
Uses
Linen uses range from bed and bath fabrics (tablecloths, dish towels, bed sheets, etc.), home and commercial furnishing items (wallpaper/wall coverings, upholstery, window treatments, etc.), apparel items (suits, dresses, skirts, shirts, etc.), to industrial products (luggage, canvases, sewing thread, etc.).[5] It was once the preferred yarn for handsewing the uppers of moccasin-style shoes (loafers), but its use has been replaced by synthetics.
A linen handkerchief, pressed and folded to display the corners, was a standard decoration of a well-dressed man's suit during most of the first part of the 20th century.
Currently researchers are working on a cotton/flax blend to create new yarns which will improve the feel of denim during hot and humid weather.
Linen fabric is one of the preferred traditional supports for oil painting. In the United States cotton is popularly used instead as linen is many times more expensive there, restricting its use to professional painters. In Europe however,
Linen is also used extensively by artisan bakers. Known as a couche, the flax cloth is used to hold the dough into shape while in the final rise, just before baking.
In the past, linen was also used for books Due to its strength, in the Middle Ages linen was used for shields and gambeson (among other roles such as use for a bowstring), much as in classical antiquity it was used to make a type of body armour, referred to as a linothorax. Also because of its strength when wet, Irish linen is a very popular wrap of pool/billiard cues, due to its absorption of sweat from hands. Paper made of linen can be very strong and crisp, which is why the United States and many other countries print their currency on paper that is made from 25% linen and 75% cotton.
Natural fibers can be defined as substances produced by plants and animals that can be spun into filament, thread or rope and in a next step be woven, knitted, matted or bound.
Cellulose
Cellulose is an organic compound with the formula (C6H10O5)n, a polysaccharide consisting of a linear chain of several hundred to many thousands. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth.
The cellulose content of cotton fiber is 90%, that of wood is 40–50% and that of dried hemp is approximately 45%.
Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Cellulose for industrial use is mainly obtained from wood pulp and cotton.Structure and properties
Cellulose has no taste, is odorless, is hydrophilic with the contact angle of 20–30, is insoluble in water and most organic solvents, is chiral and is biodegradable. It can be broken down chemically into its glucose units by treating it with concentrated acids at high temperature.
Cellulose is a straight chain polymer: unlike starch, no coiling or branching occurs, and the molecule adopts an extended and rather stiff rod-like conformation, aided by the equatorial conformation of the glucose residues. The multiple hydroxyl groups on the glucose from one chain form hydrogen bonds with oxygen atoms on the same or on a neighbor chain, holding the chains firmly together side-by-side and forming microfibrils with high tensile strength. This confers tensile strength in cell walls, where cellulose microfibrils are meshed into a polysaccharide matrix.
Cotton fibres represent the purest natural form of cellulose, containing more than 90% of this polysaccharide.Compared to starch, cellulose is also much more crystalline. Whereas starch undergoes a crystalline to amorphous transition when heated beyond 60–70 °C in water (as in cooking), cellulose requires a temperature of 320 °C and pressure of 25 MPa to become amorphous in water.
Many properties of cellulose depend on its chain length or degree of polymerization, the number of glucose units that make up one polymer molecule. Cellulose from wood pulp has typical chain lengths between 300 and 1700 units; cotton and other plant fibers as well as bacterial cellulose have chain lengths ranging from 800 to 10,000 units. Molecules with very small chain length resulting from the breakdown of cellulose are known as cellodextrins; in contrast to long-chain cellulose, cellodextrins are typically soluble in water and organic solvents.
Cellulose is soluble in Schweizer's reagent, cupriethylenediamine (CED), cadmiumethylenediamine (Cadoxen), N-methylmorpholine N-oxide, and lithium chloride / dimethylacetamide.[16] This is used in the production of regenerated celluloses (such as viscose and cellophane) from dissolving pulp. Cellulose is also soluble in many kinds of ionic liquids.
Cellulose consists of crystalline and amorphous regions. By treating it with strong acid, the amorphous regions can be broken up, thereby producing nanocrystalline cellulose, a novel material with many desirable properties. Recently, nanocrystalline cellulose was used as the filler phase in bio-based polymer matrices to produce nanocomposites with superior thermal and mechanical properties
Applications
A strand of cellulose (conformation Iα), showing the hydrogen bonds (dashed) within and between cellulose molecules.
Cellulose for industrial use is mainly obtained from wood pulp and cotton.[6] The kraft process is used to separate cellulose from lignin, another major component of plant matter.
- Paper products: Cellulose is the major constituent of paper, paperboard, and card stock.
- Fibers: Cellulose is the main ingredient of textiles made from cotton, linen, and other plant fibers. It can be turned into rayon, an important fiber that has been used for textiles since the beginning of the 20th century. Both cellophane and rayon are known .
- Consumables: Microcrystalline cellulose (E460i) and powdered cellulose (E460ii) are used as inactive fillers in drug tablets[30] and as thickeners and stabilizers in processed foods. Cellulose powder is, for example, used in Kraft's Parmesan cheese to prevent caking inside-of the package.
- Science: Cellulose is used in the laboratory as a stationary phase for thin layer chromatography. Cellulose fibers are also used in liquid filtration, sometimes in combination with diatomaceous earth or other filtration media, to create a filter bed of inert material.
- Energy crops:
The major combustible component of non-food energy crops is cellulose, with lignin second. Non-food energy crops produce more usable energy than edible energy crops (which have a large starch component), but still compete with food crops for agricultural land and water resources.[31] Typical non-food energy crops include industrial hemp (though outlawed in some countries), switchgrass, Miscanthus, Salix (willow), and Populus (poplar) species. - Biofuel: TU-103, a strain of Clostridium bacteria found in zebra waste, can convert nearly any form of cellulose into butanol fuel.
- Building material: Hydroxyl bonding of cellulose in water produces a sprayable, moldable material as an alternative to the use of plastics and resins. The recyclable material can be made water- and fire-resistant. It provides sufficient strength for use as a building material.[34] Cellulose insulation made from recycled paper is becoming popular as an environmentally preferable material for building insulation. It can be treated with boric acid as a fire retardant.
- Miscellaneous: Cellulose can be converted into cellophane, a thin transparent film. It is the base material for the celluloid that was used for photographic and movie films until the mid-1930s. Cellulose is used to make water-soluble adhesives and binders such as methyl cellulose and carboxymethyl cellulose which are used in wallpaper paste. Cellulose is further used to make hydrophilic and highly absorbent sponges. Cellulose is the raw material in the manufacture of nitrocellulose (cellulose nitrate) which is used in smokeless gunpowder.
Jute
Jute" is the name of the plant or fiber that is used to make burlap, Hessian or gunny cloth. Jute is one of the most affordable natural fibers and is second only to cotton in amount produced and variety of uses of vegetable fibers.
Jute fibers are composed primarily of the plant materials cellulose and lignin. It falls into the bast fibre category (fiber collected from bast, the phloem of the plant, sometimes called the "skin") along with kenaf, industrial hemp, flax (linen), ramie, etc.
The industrial term for jute fiber is raw jute. The fibers are off-white to brown, and 1–4 metres (3–13 feet) long.
Jute is also called "the golden fiber" for its color and high cash value
Uses
Making twine, rope, and making matting are among its uses.
Together with the sugar can be used to build aeroplane panels.
Jute is in great demand due to its cheapness, softness, length, lustre and uniformity of its fibre. It is also called the 'golden fibre' due to its versatile nature.It is called the 'brown paper bag' as it is also used to store rice, wheat, grains, etc.
Fiber
Jute fabric
Coffee sacks made of jute.
Jute fiber is extracted from retted stem of jute plantsJute matting is used to prevent flood erosion while natural vegetation becomes established. For this purpose, a natural and biodegradable fiber is essential.
Jute is the second most important vegetable fiber after cotton due to its versatility. Jute is used chiefly to make cloth for wrapping bales of raw cotton, and to make sacks and coarse cloth. The fibers are also woven into curtains, chair coverings, carpets, area rugs, hessian cloth, and backing for linoleum.
While jute is being replaced by synthetic materials in many of these uses, some uses take advantage of jute's biodegradable nature, where synthetics would be unsuitable. Examples of such uses include containers for planting young trees, which can be planted directly with the container without disturbing the roots, and land restoration where jute cloth prevents erosion occurring while natural vegetation becomes established.
Jute is regularly used in the production of clothes, particularly sweaters and underwear. Its soft fabric structure is known to be very comfortable to the person wearing it and therefore, popularity for jute clothes has increased significantly over the last decade.[citation needed]
The fibers are used alone or blended with other types of fiber to make twine and rope. Jute butts, the coarse ends of the plants, are used to make inexpensive cloth. Conversely, very fine threads of jute can be separated out and made into imitation silk. As jute fibers are also being used to make pulp and paper, and with increasing concern over forest destruction for the wood pulp used to make most paper, the importance of jute for this purpose may increase. Jute has a long history of use in the sackings, carpets, wrapping fabrics (cotton bale), and construction fabric manufacturing industry.
Traditionally jute was used in traditional textile machineries as textile fibers having cellulose (vegetable fiber content) and lignin (wood fiber content). But, the major breakthrough came when the automobile, pulp and paper, and the furniture and bedding industries started to use jute and its allied fibers with their non-woven and composite technology to manufacture nonwovens, technical textiles, and composites. Therefore, jute has changed its textile fiber outlook and steadily heading towards its newer identity, i.e., wood fiber. As a textile fiber, jute has reached its peak from where there is no hope of progress, but as a wood fiber jute has many promising features.
Jute is used in the manufacture of a number of fabrics such as Hessian cloth, sacking, scrim, carpet backing cloth (CBC), and canvas. Hessian, lighter than sacking, is used for bags, wrappers, wall-coverings, upholstery, and home furnishings. Sacking, a fabric made of heavy jute fibers, has its use in the name. CBC made of jute comes in two types. Primary CBC provides a tufting surface, while secondary CBC is bonded onto the primary backing for an overlay. Jute packaging is used as an eco-friendly substitute.
Diversified jute products are becoming more and more valuable to the consumer today. Among these are espadrilles, soft sweaters and cardigans, floor coverings, home textiles, high performance technical textiles, Geotextiles, composites, and more.
Jute floor coverings consist of woven and tufted and piled carpets. Jute Mats and mattings with 5 / 6 mts width and of continuous length are easily being woven in Southern parts of India, in solid and fancy shades, and in different weaves like, Boucle, Panama, Herringbone, etc. Jute Mats & Rugs are made both through Powerloom & Handloom, in large volume from Kerala, India. The traditional Satranji mat is becoming very popular in home décor. Jute non-wovens and composites can be used for underlay, linoleum substrate, and more.
Jute has many advantages as a home textile, either replacing cotton or blending with it. It is a strong, durable, color and light-fast fiber. Its UV protection, sound and heat insulation, low thermal conduction and anti-static properties make it a wise choice in home décor. Also, fabrics made of jute fibers are carbon-dioxide neutral and naturally decomposable. These properties are also why jute can be used in high performance technical textiles.[7]
Moreover, jute can be grown in 4–6 months with a huge amount of cellulose being produced from the jute hurd (inner woody core or parenchyma of the jute stem) that can meet most of the wood needs of the world. Jute is the major crop among others that is able to protect deforestation by industrialisation.[clarification needed]
Thus, jute is the most environment-friendly fiber starting from the seed to expired fiber, as the expired fibers can be recycled more than once.
Jute is also used to make ghillie suits, which are used as camouflage and resemble grasses or brush.
Another diversified jute product is Geotextiles, which made this agricultural commodity more popular in the agricultural sector. It is a lightly woven fabric made from natural fibers that is used for soil erosion control, seed protection, weed control, and many other agricultural and landscaping uses. The Geotextiles can be used more than a year and the bio-degradable jute Geotextile left to rot on the ground keeps the ground cool and is able to make the land more fertile.
Culinary usesIn Nigeria, leaves of Corchorus olitorius are prepared in sticky soup called ewedu together with ingredients such as sweet potato, dried small fish or shrimp.[16] The leaves are rubbed until foamy or sticky before adding to the soup. Amongst the Yoruba of Nigeria, the leaves are called Ewedu, and in the Hausa-speaking northern Nigeria, the leaves are called turgunuwa or lallo. The jute leaves are cut into shreds and added to the soup which would normally contain other ingredients such as meat and/or fish, pepper, onions, and other spices. Likewise, the Lugbara of Northwestern Uganda eat the leaves as soup, locally called pala bi. Jute is also a totem for Ayivu, one of the Lugbara clans.
In the Philippines, especially in Ilocano-dominated areas, this vegetable, locally known as saluyot, can be mixed with either bitter gourd, bamboo shoots, loofah, or sometimes all of them. These have a slimy and slippery texture.
Jute stalks are being dehydrated under the sun, later they will be used as fuel.Diversified byproducts from jute can be used in cosmetics, medicine, paints, and other products.
Features
Jute fiber is 100% bio-degradable and recyclable and thus environmentally friendly.
- Jute has low pesticide and fertilizer needs.
- It is a natural fiber with golden and silky shine and hence called The Golden Fiber.
- It is the cheapest vegetable fiber procured from the bast or skin of the plant's stem.
- It is the second most important vegetable fiber after cotton, in terms of usage, global consumption, production, and availability.
- It has high tensile strength, low extensibility, and ensures better breathability of fabrics. Therefore, jute is very suitable in agricultural commodity bulk packaging.
- It helps to make best quality industrial yarn, fabric, net, and sacks. It is one of the most versatile natural fibers that has been used in raw materials for packaging, textiles, non-textile, construction, and agricultural sectors. Bulking of yarn results in a reduced breaking tenacity and an increased breaking extensibility when blended as a ternary blend.
- The best source of jute in the world is the Bengal Delta Plain in the Ganges Delta, most of which is occupied by Bangladesh.
- Advantages of jute include good insulating and antistatic properties, as well as having low thermal conductivity and a moderate moisture regain. Other advantages of jute include acoustic insulating properties and manufacture with no skin irritations.
- Jute has the ability to be blended with other fibers, both synthetic and natural, and accepts cellulosic dye classes such as natural, basic, vat, sulfur, reactive, and pigment dyes. As the demand for natural comfort fibers increases, the demand for jute and other natural fibers that can be blended with cotton will increase. To meet this demand, some manufactures in the natural fiber industry plan to modernize processing with the Rieter's Elitex system. The resulting jute/cotton yarns will produce fabrics with a reduced cost of wet processing treatments. Jute can also be blended with wool. By treating jute with caustic soda, crimp, softness, pliability, and appearance is improved, aiding in its ability to be spun with wool. Liquid ammonia has a similar effect on jute, as well as the added characteristic of improving flame resistance when treated with flameproofing agents.
- Some noted disadvantages include poor drapability and crease resistance, brittleness, fiber shedding, and yellowing in sunlight. However, preparation of fabrics with castor oil lubricants result in less yellowing and less fabric weight loss, as well as increased dyeing brilliance. Jute has a decreased strength when wet, and also becomes subject to microbial attack in humid climates. Jute can be processed with an enzyme in order to reduce some of its brittleness and stiffness. Once treated with an enzyme, jute shows an affinity to readily accept natural dyes, which can be made from marigold flower extract. In one attempt to dye jute fabric with this extract, bleached fabric was mordanted with ferrous sulphate, increasing the fabric's dye uptake value. Jute also responds well to reactive dyeing. This process is used for bright and fast coloured value-added diversified products made from jute.
Coir
Coir is a natural fibre extracted from the husk of coconut and used in products such as floor mats, doormats, brushes, mattresses, etc. Coir is the fibrous material found between the hard, internal shell and the outer coat of a coconut. Other uses of brown coir (made from ripe coconut) are in upholstery padding, sacking and horticulture. White coir, harvested from unripe coconuts, is used for making finer brushes, string, rope and fishing netsCoir fibres are found between the hard, internal shell and the outer coat of a coconut. The individual fibre cells are narrow and hollow, with thick walls made of cellulose. They are pale when immature, but later become hardened and yellowed as a layer of lignin is deposited on their walls. Each cell is about 1 mm (0.04 in) long and 10 to 20 µm (0.0004 to 0.0008 in) in diameter. Fibres are typically 10 to 30 centimetres (4 to 12 in) long.Uses
Red coir is used in floor mats and doormats, brushes, mattresses, floor tiles and sacking. A small amount is also made into twine. Pads of curled brown coir fibre, made by needle-felting (a machine technique that mats the fibres together), are shaped and cut to fill mattresses and for use in erosion control on river banks and hillsides. A major proportion of brown coir pads are sprayed with rubber latex which bonds the fibres together (rubberised coir) to be used as upholstery padding for the automobile industry in Europe. The material is also used for insulation and packaging.
The major use of white coir is in rope manufacture. Mats of woven coir fibre are made from the finer grades of bristle and white fibre using hand or mechanical looms. White coir also is used to make fishing nets due to its strong resistance to saltwater.
In horticulture, coir is a substitute for sphagnum moss because it is free of bacteria and fungal spores. Coir is also useful to deter snails from delicate plantings, and as a growing medium in intensive glasshouse (greenhouse) horticulture.[citation needed]
Coconut coir from Mexico has been found to contain large numbers of colonies of the beneficial fungus Aspergillus terreus, which acts as a biological control against plant pathogenic fungi.
Coir is also used as a substrate to grow mushrooms. The coir is usually mixed with vermiculite and pasteurized with boiling water. After the coir/vermiculite mix has cooled to room temperature, it is placed in a larger container, usually a plastic box. Previously prepared spawn jars are then added, spawn is usually grown in jars using substrates such as rye grains or wild bird seed. This spawn is the mushrooms mycelium and will colonize the coir/vermiculite mix eventually fruiting mushrooms.
Coir is an allergen, as well as the latex and other materials used frequently in the treatment of coir.
Coir can be used as a terrarium substrate for reptiles or arachnids.
Linen
Linen
is a textile made from the fibers of the flax plant, Linum usitatissimum. Linen is laborious to manufacture, but the fiber is very absorbent and garments made of linen are valued for their exceptional coolness and freshness in hot weather.
Many products are made of linen: aprons, bags, towels (swimming, bath, beach, body and wash towels), napkins, bed linens, tablecloths, runners, chair covers, and men's and women's wear.
PropertiesLinen fabric feels cool to the touch. It is smooth, making the finished fabric lint-free, and gets softer the more it is washed.
Linen fabrics have a high natural luster; their natural color ranges between shades of ivory, ecru, tan, or grey. Pure white linen is created by heavy bleaching. Linen fabric typically varies somewhat in thickness and is crisp and textured, but it can in some cases feel stiff and rough, and in other cases feel soft and smooth.
Linen is a very durable, strong fabric, and one of the few that are stronger wet than dry. The fibers do not stretch, and are resistant to damage from abrasion. However, because linen fibers have a very low elasticity, the fabric eventually breaks if it is folded and ironed at the same place repeatedly over time.
Mildew, perspiration, and bleach can also damage the fabric, but it is resistant to moths and carpet beetles. Linen is relatively easy to take care of, since it resists dirt and stains, has no lint or pilling tendency, and can be dry-cleaned, machine-washed or steamed.
Linen should not be dried too much by tumble drying, and it is much easier to iron when damp. Linen wrinkles very easily, and thus some more formal garments require ironing often, in order to maintain perfect smoothness.
Uses
Linen uses range from bed and bath fabrics (tablecloths, dish towels, bed sheets, etc.), home and commercial furnishing items (wallpaper/wall coverings, upholstery, window treatments, etc.), apparel items (suits, dresses, skirts, shirts, etc.), to industrial products (luggage, canvases, sewing thread, etc.).[5] It was once the preferred yarn for handsewing the uppers of moccasin-style shoes (loafers), but its use has been replaced by synthetics.
A linen handkerchief, pressed and folded to display the corners, was a standard decoration of a well-dressed man's suit during most of the first part of the 20th century.
Currently researchers are working on a cotton/flax blend to create new yarns which will improve the feel of denim during hot and humid weather.
Linen fabric is one of the preferred traditional supports for oil painting. In the United States cotton is popularly used instead as linen is many times more expensive there, restricting its use to professional painters. In Europe however,
Linen is also used extensively by artisan bakers. Known as a couche, the flax cloth is used to hold the dough into shape while in the final rise, just before baking.
In the past, linen was also used for books Due to its strength, in the Middle Ages linen was used for shields and gambeson (among other roles such as use for a bowstring), much as in classical antiquity it was used to make a type of body armour, referred to as a linothorax. Also because of its strength when wet, Irish linen is a very popular wrap of pool/billiard cues, due to its absorption of sweat from hands. Paper made of linen can be very strong and crisp, which is why the United States and many other countries print their currency on paper that is made from 25% linen and 75% cotton.
Unit-III (Compounding of additives)
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Unit-IV (Mixing machinery and devices)
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