Nylon - 6 modified with poly ethylene glycol diamines of low molecular weight

摘要

Novel modified nylon-6 may be produced by using a combination of one or more dicarboxylic acids and triethylene glycol diamine and tetraethylene glycol diamine, but not a diethylene glycol diamine. A dicarboxylic acid/polyethylene glycol diamine salt may be reacted with . epsilon.-caprolactam to provide the modified nylon-6. The diamines have the formula NH.sub.2 --(CH.sub.2 CH.sub.2 O).sub.x --CH.sub.2 CH.sub.2 -- NH.sub.2, where x ranges from 2 to 3. Surprisingly, the suitable diamines include triethylene glycol diamine (x=2; JEFFAMINE® EDR-148 Amine) and tetraethylene glycol diamine (x=3; JEFFAMINE® EDR-192 Amine), but not closely related bis-aminoethyl ether (x=1; BAEE). Unexpectedly, BAEE, which only differs from JEFFAMINE EDR-148 Amine by one --13 (CH.sub.2 CH. sub.2 O)--group, did not give satisfactory product--the fibers were too weak. The resulting modified nylon-6 polymers of the invention, however, including fibers therefrom, have improved water absorbancy properties and greater flexibility. Polyamide products with a wide range of water adsorbancies may be obtained by adjusting the amount of amide.