Abstract: A process for removing volatile constituents from polymer melts or pastes, wherein the polymer or paste containing the volatile constituents is passed, with continuous formation of fresh surfaces, through one or more zones in which the volatile constituents evaporate, and the volatile constituents are removed from the zone or zones in which they evaporate through, in each case, a plurality of porous orifices, and an apparatus for carrying out said process.

Abstract: Nylons are prepared by a continuous process in which, in an evaporator zone, an aqueous solution of a salt of a dicarboxylic acid of 6 to 18 carbon atoms and a diamine of 6 to 18 carbon atoms is heated to 250.degree.-300.degree. C. under superatmospheric pressure, with simultaneous vaporization of water and formation of a prepolymer, the prepolymer and the vapors are separated continuously, the vapors are rectified and the entrained diamines are recycled, and the prepolymer is fed to a polycondensation zone and subjected to polycondensation under superatmospheric pressure of from 1 to 10 bar and at from 250.degree. to 300.degree. C., wherein the aqueous salt solution is heated under superatmospheric pressure of from 1 to 10 bar during a residence time of less than 60 seconds, with the proviso that, on leaving the evaporator zone, the degree of conversion is not less than 93% and the water content of the prepolymer is not more than 7% by weight.