Polyamides for extrusion applications

摘要

There is disclosed a process for preparing polycarbodiimide modified tractable polyamides having unique rheological properties which include increased melt strength and relative viscosity. These polycarbodiimide modified tractable polyamides are prepared by reacting the carboxyl end groups and to a lesser degree the amine end groups of tractable polyamides such as nylon 6,6, which are in a molten state with the polycarbodiimide groups of at least one polycarbodiimide such as poly(4,4'-diphenyl-methane carbodiimide) which both (a) is derived from at least one aromatic diisocyanate which is either unsubstituted or contains up to one methyl substituent on each aromatic ring, and (b) contains at least three carbodiimide units per polycarbodiimide molecule.