Simple Synthesis of a Large Amount of a Biodegradable Polyamide and Design of Its processing and Degradation systems

高真空条件下2-吡咯烷酮的提纯和聚合是制备高相对分子质量尼龙4所必需的，但有时会干扰其大规模的制备。为了放大2-吡咯烷酮的聚合，本工作在氮气气氛中进行，2-吡咯烷酮的阴离子聚合一次可得到80g以上的低分子量尼龙4，经减压蒸馏和活化分子筛干燥，而不是通过使用前的水合物重结晶。另一方面，2-吡咯烷酮水合物经分子筛蒸馏干燥重结晶后得到的2-吡咯烷酮是制备高相对分子质量尼龙的关键。因此，在干燥的氮气气氛下一次聚合可以得到100g以上的高相对分子质量尼龙4，而不是在高真空条件下。通过对尼龙4的酰内酰胺链端进行化学修饰，提高了尼龙4的热稳定性。

The strict procedures for the purification and polymerization of 2-pyrrolidone in high vacuum line are necessary for the preparation of high molecular weight nylon4, which disturb its preparation on a large scale at a time. In order to scale up the polymerization of 2-pyrrolidone, the procedures were performed in an atmosphere of prepurified nitrogen in the present work.More than 80 grams of low molecular weight nylon4 was obtained at a time on the anionic polymerization of 2-pyrrolidone which was purified by the distillation under reduced pressure and the subsequent drying on the activated molecular sieves, but not through the recrystallization of its hydrate before use. On the other hand, the purification of 2-pyrrolidone through the recrystallization of its hydrate subsequently by the distillation and drying on the molecular sieves was essential for the preparation of the high molecular weight nylon4. Thus more than 100g of the high molecular weight nylon4 was obtained on one polymerization procedure under dry nitrogen atmosphere but not in a high vacuum line.The thermal stability of nylon4 was found to increase through the chemical modification of its acyllactam-type chain end.