Copolymer

In <a href="/facts/Polymer_chemistry/wdfr6fs4">polymer chemistry</a>, a copolymer is a <a href="/facts/Polymer/eF32E50K">polymer</a> derived from more than one species of <a href="/facts/Monomer/Gw3CltMb">monomer</a>. The <a href="/facts/Polymerization/1hmBz7Ur">polymerization</a> of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are sometimes called bipolymers. Those obtained from three and four monomers are called terpolymers and quaterpolymers, respectively. Copolymers can be characterized by a variety of techniques such as <a href="/facts/Nuclear_magnetic_resonance_spectroscopy/SFKgdthI">NMR spectroscopy</a> and <a href="/facts/Size-exclusion_chromatography/6IxgVPI1">size-exclusion chromatography</a> to determine the molecular size, weight, properties, and composition of the material.
Commercial copolymers include <a href="/facts/Acrylonitrile_butadiene_styrene/WrksnpMv">acrylonitrile butadiene styrene</a> (ABS), <a href="/facts/Styrene%2fbutadiene_co-polymer/HgU5cek0">styrene/butadiene co-polymer</a> (SBR), <a href="/facts/Nitrile_rubber/teqn52n5">nitrile rubber</a>, <a href="/facts/Styrene-acrylonitrile/JJCyq97G">styrene-acrylonitrile</a>, styrene-isoprene-styrene (SIS) and <a href="/facts/Ethylene-vinyl_acetate/kYxe810A">ethylene-vinyl acetate</a>, all of which are formed by <a href="/facts/Chain-growth_polymerization/ltonCdDy">chain-growth polymerization</a>. Another production mechanism is <a href="/facts/Step-growth_polymerization/MHMGpt0g">step-growth polymerization</a>, which is used to produce the nylon-12/6/66 copolymer of <a href="/facts/Nylon_12/lYKcUNYp">nylon 12</a>, <a href="/facts/Nylon_6/8Dtq3N7z">nylon 6</a> and <a href="/facts/Nylon_66/tPvwq7aw">nylon 66</a>, as well as the <a href="/facts/Copolyester/qlTyWRYJ">copolyester</a> family. Copolymers can be used to develop commercial goods or drug delivery vehicles.

 
Since a copolymer consists of at least two types of constituent units (also <a href="/facts/Structural_unit/XGlAYDb0">structural units</a>), copolymers can be classified based on how these units are arranged along the <a href="/facts/Catenation/vm7k4zsv">chain</a>. Linear copolymers consist of a single <a href="/facts/Backbone_chain/9Q3so597">main chain</a> and include <a href="/facts/Alternating_copolymer/35D97DuV">alternating copolymers</a>, <a href="/facts/Statistical_copolymer/35D97DuV">statistical copolymers</a>, and <a href="/facts/Block_copolymer/35D97DuV">block copolymers</a>. <a href="/facts/Branching_(polymer_chemistry)/KYF9YA1j">Branched</a> copolymers consist of a single main chain with one or more polymeric <a href="/facts/Side_chain/Lw8KPAXn">side chains</a>, and can be <a href="/facts/Graft_polymer/JymnzUdJ">grafted</a>, star shaped, or have other architectures.

Copolymer open-in-new

Copolymer