Synthetic Fibres & Plastics

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<p>Synthetic Fibres</p> <p>Synthetic Fibres &amp; Plastics Synthetic Fibres Synthetic fibresare the result of extensive research byscientiststo improve on naturally occurringanimalandplantfibres. In general,synthetic fibres are created by forcing, usually throughextrusion, fibre forming materials through holes (called spinnerets) into the air, forming a thread.</p> <p>Synthetic Fibres</p> <p>Nylon (Monomer- Hexamethylene) </p> <p> Nylonis a generic designation for a family ofsynthetic polymersknown generically aspolyamides, first produced on February 28, 1935, byWallace Carothers.</p> <p>Polyester (Monomer- Ester) </p> <p> Polyesteris a category ofpolymerswhich contain theesterfunctional groupin their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers topolyethylene terephthalate(PET).</p> <p>Rayon (Monomer-Cellulose) Rayonis a manufactured regeneratedcellulose fibre. Because it is produced from naturally occurringpolymers, it is neither a trulysynthetic fibrenor anatural fibre; it is asemi-synthetic</p> <p>Acrylic (Monomer- Polyacrylonitrile) Acrylic fibersaresynthetic fibersmade from a polymer (polyacrylonitrile) with an average molecular weight of ~100,000, about 1900 monomer units</p> <p>Disadvantages of SyntheticsSynthetic fibers melt before burningSome electrical charge accumulates on the synthetic fibers. The electrical charge causes irritation of the skin.Extremely hazardous to the environment.Can make you overheatCan make you cold when wet</p> <p>Advantages of SyntheticsSynthetic fibers do not depend either on an agricultural crop or on animal farming.They are generally cheaper than natural fibre.Synthetic fibers possess unique characteristics which make them popular dress material.They dry up quickly, are durable, readily available and easy to maintain.</p> <p>PlasticsPlasticsAplasticmaterial is any of a wide range ofsyntheticor semi-syntheticorganicsolids that aremouldable. Plastics are typicallyorganic polymersof highmolecular mass, but they often contain other substances. They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural.</p> <p>ThermoplasticsAThermoplastic, also known as athermosoftening plastic, is apolymerthat becomes pliable or moldable above a specific temperature, and returns to a solid state upon cooling</p> <p>Thermosetting PlasticsAthermosetting plastic, also known as athermoset, ispolymermaterial that irreversiblycures. The cure may be done through heat (generally above200 C(392F)), through a chemical reaction (two-partepoxy, for example), orirradiationsuch aselectron beam processing.</p> <p>Be AlertMelamine Cancer If you eat in a Melamine Plate, you may become a victim of Melamine Cancer. Melamine is a thermosetting plastic and is non-biodegradable. While eating when we scratch the plate with the spoon, the melamine coating also goes into our body which may cause Cancer. Check under your plates whether Melamine made is written or not. Use Bone China, Glass or Steel Plates instead</p> <p>Plastic.Harm to EnvironmentPlastics have transformed modern society, providing attractive benefits but also befouling waterways and aquifers, depleting petroleum supplies and disrupting human health.</p> <p>The 3 RsReducing the amount of waste you produce is the best way to help the environment. Instead of throwing things away, try to find ways to use them again! Many of the things we use every day, like paper bags, soda cans, and milk cartons, are made out of materials that can be recycled.</p> <p> Shivam pratap</p>

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