Determination of Compositional Heterogeneity of Polyamide Copolymers

Abstract

A gel permeation chromatograph equipped with dual detectors provides very useful information on compositional and molecular weight distributions. One copolymer composed of nylon 12 and polytetramethylene ether glycol, and the other of nylon 6 and natural rubber were discussed in this study. By trifluoroacetylation of the amide group, these polymers became soluble in common solvents such as dichlcromethane and tetrachloroethane. Good chromatograms were obtained using these solvents for the above copolymers. At the same time, the compositional heterogeneity was determined from the chromatograms obtained with refractive index and ultraviolet detectors.