| 摘要 |
2082826 9118024 PCTABS00008 What is described herein is a process for making copolymers of maleic anhydride and C1-C4 alkyl vinyl ethers of predetermined specific viscosities extending over a wide viscosity range. The invention is characterized by (a) precharging a reactor with a C1-C4 alkyl vinyl ether as solvent and a polymerization initiator at a reaction temperature, (b) feeding a mixture of maleic anhydride and a C1-C4 alkyl vinyl ether in substantially stoichiometric amounts, preferably with a slight excess of alkyl ether, and at a selected rate, into said precharged reactor, (c) polymerizing said reactants to form a slurry of said copolymer in said excess alkyl vinyl ether solvent, and (d) introducing toluene into said reactor during the polymerization to control the specific viscosity of the copolymer product being produced.
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