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Artificial polymer: Man-made polymer that is not a biopolymer. Note 1: Artificial polymer should also be used in the case of chemically modified biopolymers. Note 2: Biochemists are now capable of synthesizing copies of biopolymers that should be named Synthetic biopolymer to make a distinction with true biopolymers.
A polymer (/ ˈ p ɒ l ɪ m ər / [4] [5]) is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. [6]
Polymers, strictly speaking, comprise most solid matter: minerals (i.e. most of the Earth's crust) are largely polymers, metals are 3-d polymers, organisms, living and dead, are composed largely of polymers and water. Often polymers are classified according to their origin: biopolymers; synthetic polymers; inorganic polymers
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).
Polystyrene (PS) / ˌ p ɒ l i ˈ s t aɪ r iː n / is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. [5] Polystyrene can be solid or foamed . General-purpose polystyrene is clear, hard, and brittle.
The company Thiokol applied their name to a competing type of rubber based on ethylene dichloride. [4] In 1935, German chemists synthesized the first of a series of synthetic rubbers known as Buna rubbers. These were copolymers, meaning the polymers were made up from two monomers in alternating sequence.
Such polymers contain structures that impart high melting temperatures, resistance to oxidative degradation and stability to radiation and chemical reagents. Among the thermally stable polymers with commercial relevance are polyimides, polysulfones, polyetherketones, and polybenzimidazoles. Of these, polyimides are most widely applied. [14]
Another synthetic polymer, sometimes called by the same general category, is acetal resin. By contrast with the other synthetics, however, it has a simple chain structure with the repeat unit of form −[CH 2 O]−. Ion-exchange resins are used in water purification and catalysis of organic reactions. (See also AT-10 resin, melamine resin.)