Environmental Engineering Reference
In-Depth Information
Since these are equilibrium reactions, the water or other small molecular
product needs to be removed from the mixture to encourage the reaction to
proceed in the forward direction. Another example is the condensation of
bisphenol A monomer with phosgene to yield PC plastic:
High molecular weights are obtained in condensation polymerization but
only at very high percent conversions of monomer or where nearly all the
functional groups are reacted. High conversion is encouraged by carefully
matching the stoichiometry of end groups. A variant of this reaction is when
bothreactive functional groupsarelocatedonthesamemolecule(suchasin
the case of hydroxy acids). If one or both of the monomers have more than
two functional groups per molecule, then condensation reaction will yield a
branched polymer.
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