Research on preparation of poly(1, 4-phenylene-terephthalamide) with in-situ phase transition aided heat transfer and its engineering scale study

Abstract

Thermal management of the polymerization reaction process is one of key factors influencing polymer quality and success in engineering scale-up. Liquid nitrogen is introduced in PPTA polymerization process in the paper, so as to investigate influence on PPTA polymerization process and polymer performance when the inertia heat transfer medium of liquid nitrogen is adopted as the auxiliary heat transfer medium during polycondensation of traditional cryogenic fluid. It is indicated from results that addition of proper amount of liquid nitrogen during PPTA polymerization process can improve logarithmic viscosity and thermal stability, and improve the surface wettability of PPTA. It will not cause obvious influence on the chemical structure, aggregation structure and liquid crystal pattern of PPTA. The logarithmic viscosities of polymer obtained from the polymerization scale-up experiment of 140, 300 and 1000 L reaction vessels are above 6 dL/g.