非溶剂法合成N-乙烯基己内酰胺的反应选择性研究

Selectivity in Synthesis of N-vinylcaprolactam Without Solvent

采用非溶剂法,将己内酰胺与乙炔在催化剂、助催化剂以及在阻聚剂的作用下合成乙烯基己内酰胺,考察合成工艺参数对反应选择性的影响,并通过红外确认目标产物。结果表明温度95~100℃、以对叔丁基邻苯二酚或自制复合阻聚剂2为阻聚剂、投入己内酰胺质量为反应器容积的55%时,反应的选择性较好,加入18-冠醚-6可以稍提高反应选择性,最终反应的选择性可以达到95%左右。压力对反应选择性的影响较小,所得产物红外图谱与N-乙烯基己内酰胺标准样红外图谱一致。

N-Vinylcaprolactam was synthesized with no solvent,using caprolactam and acetylene as raw materials,with catalyst,cocatalyst and polymerization inhibitor as additives.The effects of different conditions on reaction selectivity were studied and the product was confirmed by infrared spectroscopy.It indicated that when reaction temperature is 95~100℃,using TBC or self-made polymerization inhibitor 2 as polymerization inhibitor,the weight of caprolactam is 55%of the reactor volume,then the reaction selectivity would be higher,the use of 18-crown-6 as cocatalyst will enhance the selectivity a little,and the final selectivity would be about 95%.The pressure of acetylene has no effect on selectivity.The infrared spectrum of the reaction product was consistent with the spectrum of N-vinylcaprolactam standard sample.