Blockiness

Note: Copolymers that are obtained by copolymerization of two monomer species
are sometimes termed bipolymers, those obtained from three monomers terpolymers,
those obtained from four monomers quaterpolymers, etc.

Alternating copolymers: A copolymer consisting of macromolecules comprising
two species of monomeric units in alternating sequence.

Note: An alternating copolymer may be considered as a homopolymer derived from
an implicit or hypothetical monomer.

Block copolymers: A portion of a macromolecule, comprising many constitutional
units, that has at least one feature which is not present in the adjacent portions.

When two or more different monomers unite together to polymerize, the product is called a copolymer and the process is called copolymerization.

Commercially relevant copolymers include acrylonitrile butadiene styrene (ABS), styrene/butadiene co-polymer (SBR), nitrile rubber, styrene-acrylonitrile, styrene-isoprene-styrene (SIS) and ethylene-vinyl acetate, all formed by chain-growth polymerization. Commercial examples formed by step-growth polymerization are the nylon-12/6/66 copolymer of nylon 12, nylon 6 and nylon 66, as well as the copolyester family.

Since a copolymer consists of at least two types of constituent units (also structural units), copolymers can be classified based on how these units are arranged along the chain. These include:

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