| 摘要 |
Copolymer substantially free from compositional drift can be produced in a batch-type addition copolymerization process to a high degree of conversion by initiating the reaction in a monomer-containing phase (optionally dispersed in another phase of a reaction mixture) containing the monomers at mole ratios fi such that the monomers will initially be incorporated into copolymer at the desired mole ratios Fi and sustaining the reaction while simultaneously controlling the addition each monomer to the phase in which the copolymerization reaction is continuing according to the relation Qi = fiQ0 + (Fi - fiQ0/Q INFINITY )Z, where Qi is the running cumulative moles of monomer i added to the phase in which reaction is occurring (including that initially present), Q0 is the total moles of all monomers initially present in that phase, Q INFINITY is the total moles of all monomers ultimately to be added to that phase, and Z is the running cumulative moles of all monomers converted to copolymer. Q0/Q INFINITY must not substantially exceed the smallest ratio Fi/fi for any of the monomers and in the preferred mode is made substantially equal to that smallest ratio, thereby eliminating the corresponding monomer from the continuing addition.
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