微波辐射活性炭负载钨硅酸催化合成尼泊金酸乙酯

借助微波辐射技术,以活性炭负载钨硅酸为催化剂,尼泊金酸和乙醇为原料合成了尼泊金酸乙酯。通过正交试验,探讨了影响酯化率的主要因素,确定了最佳合成条件:醇酸摩尔比为3:1,催化剂用量为反应物总质量的3%,微波输出功率为400 W,辐射时间为20 min。在此优化条件下,反应的酯化率可达97.3%。实验结果表明:活性炭负载钨硅酸对尼泊金酸乙酯的合成具有良好的催化活性,同时微波辐射加快了反应进程。

Synthesis of biodegradable poly (methylparaben/glycine ethyl ester) phosphazene and further research of its degradation in vitro

Polydichlorophosphazene(PDCP)was synthesized from PCl5 and NH4Cl via a one-pot approach,and then further reacted with glycine ethyl ester and methylparaben via a two-step nucleophilic substitution approach to give poly(methylparaben/glycine ethyl ester)phosphazene(PMGP),which was a kind of mix-substituted biodegradable polymer.NMR and FT-IR were used to characterize its structure.A series of experiments were conducted to study the effects of the ratio of methylparaben to glycine ethyl ester and the experimental conditions to the degradability of PMGP samples.The degradability of PMGP can be adjusted by altering the ratio of methylparaben to glycine ethyl ester easily.