| 摘要 |
Prodn. of acetal copolymers with simultaneous end gp. stabilisation is effected in homogeneous phase by copolymerising cyclic formaldehyde oligomers with cyclic acetal cpds. in a polymerisation reactor with addn. of a basic substance to deactivate the initiator following the copolymerisation, the process being such that the prod. (with its non-stable chain end content in presence of residual monomers reduced to 0.01-1%) is passed to a granulator where the bulk of the residual monomer is lost and the remaining residual monomers and dissolved impurities are removed by solvent extn. prior to drying and stabilising the prod. and then granulating it.
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