Minimum energy process for preparing block copolymers of polyamides

Claim 1

A process for forming a block polyamide copolymer comprising: (a) blending dry particles of a melt-spinnable polyamide and a dry salt selected from the group consisting of prepolyamides represented by the formula: ##STR10## wherein R 1 , R 2 and R 3 are selected from the group consisting of H, C 1 -C 10 alkyls and C 3 -C 10 isoalkyls; R 4 is selected from the group consisting of C 1 -C 10 alkylenes and C 3 -C 10 isoalkylenes; and R 5 is selected from the group consisting of C 6 -C 14 arylenes, C 0 -C 10 alkylenes and C 3 -C 10 isoalkylenes; wherein the salt content amounts to between from about 10 weight % to about 75 weight % of the total weight; (b) heating in an inert atmosphere resulting blend of the salt and the polyamide to a temperature in the range of between from the melting point of higher melting component to below about amide-interchange temperature of a mix of the melt spinnable polyamide and polyamide which would result from the polymerization of the salt; and (c) mixing the heated blend at the aforementioned temperature and in the inert atmosphere, until substantially all of the salt and the polyamide are converted to the block polyamide copolymer.