A NEW METHOD FOR PREPARATION OF NYLON 6 WITH HIGH CRYSTALLINITY AND SPECIAL MORPHOLOGY

摘要

@@We adopt a new facile method to modify the crystalline behavior of nylon 6 to improve the quality of nylon product. The key strategy is to utilize vapor of precipitator (such as THF, H2O) to induce crystallization of nylon from its formic acid solution at room temperature and ambient pressure. The obtained Nylon 6 samples (denoted as vp-nylon 6) exhibit improved crystallinity and perfection. Additionally, unique morphological feature is also observed. For comparison, a nylon 6 sample is prepared by using general thermal treatment processes (denoted as gt-nylon 6). That is, the nylon 6 sample is melted and kept at 280℃ to erase former thermal history, then cooled down slowly to induce the crystallization. The DSC results indicate that vpnylon 6 has not only high degree of crystalline perfection, but also high crystallinity. The DSC curve of the vp-nylon 6 exhibited only a sharp melting peak while the melting peak of the gt-nylon 6 is a wide envelope, which might be attributed to superposition of melting and pre-melting processes.