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Copolymer is the result of polymerization when two or more different monomers join together. This process is called copolymerization. When a polymer is made by linking together only one type of monomer, it is a homopolymer.


Copolymers have minimum two types of monomers and they can be made in many different ways. They are classified depending on the monomer sequence along the chain. There are alternating copolymers, block copolymers and random copolymers.

Alternating copolymers

the two monomers are arranged in an alternating way, so the polymer is called alternating copolymer.


Block copolymers

One type of monomer is linked together and the second type too, and those groups are joined together too. We can say that a block copolymer is like two homopolymers linked together. Block copolymers with two or three blocks are called diblock copolymers and triblock copolymers, respectively.


Random copolymer

The copolymer is build up with two monomers which don’t follow an order or we can also say that they follow a statistical rule.


Graft copolymer

This copolymer is made from different monomers and one of them is grafted onto a polymer chain of a second monomer, for example: Poly(styrene-butadiene-styrene) used in soles of shoes, tire treads, and other places where durability is important.


We can find several copolymers on the market including polypropylene, acrylonitrile butadiene styrene (ABS), styrene/butadiene co-polymer (SBR), styrene-isoprene-styrene (SIS) and ethylene-vinyl acetate.


  1. wiki – copolymer