Block copolymer structure (block: khối): blocks of one type of homopolymer structure are attached to blocks of another type of homopolymer structure.
Note: different block copolymer are distinguished by the number of blocks per molecule, for example:
AmBp : diblock
AmBpAm : triblock
AmBpAmBp: tetrablock
(AmBp)n : multiblock
which are referred to as AB block, ABA triblock, ABAB tetrablock, and AB multiblock copolymers, respectively. For the various block copolymers the values of m and p as well as n are average values; thus, there is a distribution of block lengths and number of blocks along the copolymer chain.
Alternating copolymer structure: groups or monomers alternate in that order over and over again along the polymer chain.
Statistical copolymer structure: there is an irregular (statistical - random) distribution of any groups along the copolymer chain.
Note: for the statistical copolymer the distribution may follow different statistical laws, for example, Bernoullian (zero-order Markov), first- or second-order Markov, depending on the specific reactants and the method of synthesis. Many statistical copolymers are produced via Bernoullian processes whrein the various groups are randomly distributed along the copolymer chain; such copolymers are random copolymers. However, most literature references use the term random copolymer independent of the type of statistical distribution. So, the types of statistical copolymer and random copolymer are different.
Graft copolymer (graft: ghép): one or more blocks of homopolymer B are grafted as branches onto a main chain of homopolymer A.
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