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In general, synthetic fibers are created by extruding fiber-forming materials through spinnerets, forming a fiber. These are called synthetic or artificial fibers. The word polymer comes from a Greek prefix "poly" which means "many" and suffix "mer" which means "single units". (Note: each single unit of a polymer is called a monomer).
The plastic kits and covers are mostly made of synthetic polymers like polythene, and tires are manufactured from polybutadienes. [1] However, due to the environmental issues created by these synthetic polymers which are mostly non-biodegradable and often synthesized from petroleum, alternatives like bioplastics are also being considered.
The first plastic made from synthetic components, it was developed by Leo Baekeland in Yonkers, New York, in 1907, and patented on December 7, 1909. [3] Bakelite was one of the first plastic-like materials to be introduced into the modern world and was popular because it could be moulded and then hardened into any shape.
Azeotrope esterification is a classical method for condensation. The water formed by the reaction of alcohol and a carboxylic acid is continually removed by azeotropic distillation. When melting points of the monomers are sufficiently low, a polyester can be formed via direct esterification while removing the reaction water via vacuum.
The development of plastics has evolved from the use of naturally plastic materials (e.g., gums and shellac) to the use of the chemical modification of those materials (e.g., natural rubber, cellulose, collagen, and milk proteins), and finally to completely synthetic plastics (e.g., bakelite, epoxy, and PVC).
The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: [1] these 24 elements were first created between 1944 and 2010. The mechanism for the creation of a synthetic element is to force additional protons into the nucleus of an element with an atomic number lower than 95.
Synthetic polymers are ubiquitous in commercial materials and products in everyday use, such as plastics, and rubbers, and are major components of composite materials. Polymer chemistry can also be included in the broader fields of polymer science or even nanotechnology , both of which can be described as encompassing polymer physics and ...
Chemical synthesis using green chemistry promotes the design of new synthetic methods and apparatus that simplify operations and seeks environmentally benign solvents. Key principles include atom economy , which aims to incorporate all reactant atoms into the final product, and the reduction of waste and inefficiencies in chemical processes.