| 摘要 |
A process for the continuous preparation of polytetramethylene adipamide, in which (a) an aqueous solution of the salt of 1,4-diaminobutane and adipic acid is heated with evaporation of water to form a vapor phase and a molten prepolymer, (b) the said prepolymer and vapor phase are passed, to effect thorough mixing thereof, through a mass transfer zone equipped with baffles and located immediately downstream of stage (a), (c) the said vapor phase is separated from the polymer in a separting zone and the polymer is discharged in the form of a melt capable of being granulated, with the proviso that the total residence time in stages (a), (b) and (c) is less than 5 minutes, and (d) pyrrolidine is distilled off from the vapor phase separated in stage (c) and 1,4-diaminobutane is recycled to the vaporizing stage (a).
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