block copolymer

chemistry

Learn about this topic in these articles:

elastomers

  • truck tires being removed from their molds
    In rubber: The rise of synthetic rubber

    For example, block copolymers, in which a long sequence of one chemical unit is followed in the same molecule by a long sequence of another, were made, using many different units and sequence lengths. New oil-resistant and heat-resistant elastomers were introduced, including the styrene-acrylonitrile copolymers, the polysulfides,…

    Read More
  • The random copolymer arrangement of styrene-butadiene copolymer. Each coloured ball in the molecular structure diagram represents a styrene or butadiene repeating unit as shown in the chemical structure formula.
    In elastomer: Block copolymers

    Another type of intermolecular association is shown by thermoplastic block copolymers, where each molecule consists of long sequences, or blocks, of one unit followed by long sequences of another. Because different polymers are generally incompatible (i.e., do not dissolve into one another), blocks…

    Read More
  • In copolyester elastomer

    Copolyester elastomers are block copolymers—that is, the two different types of chemical repeating units that make up the chainlike molecules occur in long sequences, or blocks. The hard sequences usually consist of polybutylene terephthalate (PBT), a stiff polyester resin. The soft sequences consist of any one of a…

    Read More