The invention relates to a process for preparing a melt-processable polylactam by contacting caprolactam monomer with an anionic polymerization catalyst, polymerizing said monomer and contacting the resulting polylactam with a protic compound. The anionic polymerization catalyst is chosen from the group of alkali-earth-metal-lactamates and alkali-earth-metal-lactamate forming compounds and the protic compound has a pKa larger than 14. The resulting polylactam has a good melt-stability and very low cyclic dimer content.
本发明涉及一种制备可熔融加工的聚内酰胺的工艺,其方法是将己内酰胺单体与阴离子聚合催化剂接触,使所述单体聚合,并将得到的聚内酰胺与原生化合物接触。阴离子聚合催化剂选自碱土
金属-内酰胺和碱土
金属-内酰胺形成化合物,原生化合物的 pKa 大于 14。由此制得的聚内酰胺具有良好的熔融稳定性和极低的环状二聚物含量。