高分子季铵盐型抗菌材料的制备

通过γ-氯丙基三甲氧基硅烷的偶联,将水溶性聚乙烯亚胺(PEI)接枝在纳米SiO2表面,随后分别用1-溴己烷和碘甲烷对接枝的PEI进行N-烷基化修饰,使PEI中的部分氨基转变成季铵盐,得到水不溶性QPEI/SiO2微粒。通过测定PEI/SiO2上PEI的接枝量,考察了各种反应条件对QPEI/SiO2微粒制备的影响规律。研究结果表明,纳米SiO2表面接枝PEI的适宜条件为:反应溶剂为DMF,反应温度90~100℃,反应时间8 h,氯丙基化SiO2与PEI质量比为4∶1,在此条件下制备的QPEI/SiO2微粒中PEI接枝量为14.8%。QPEI/SiO2微粒经甲基化修饰后,季铵盐含量由0.96%增加到3.37%,其抗菌性能显著增强。

Study on preparation of macromolecular quaternary ammonium salts antimicrobial materials

Water-soluble polyethylenimine(PEI) was grafted onto the surface of nano-SiO2 particles through the couple effect of γ-chloropropyltrimethoxysilane,and the water-insoluble antimicrobial SiO2 particles grafted with quaternized polyethylenimines(QPEI/SiO2) was prepared followed by the N-alkylation of coated PEI with 1-bromohexane and idomethane,respectively.The influences of various factors on the preparation of QPEI/SiO2 were examined via measuring the grafted amount of PEI on the composite of QPEI/SiO2.The results show that the optimum reaction conditions are as follows:the reaction temperature is 90～100 ℃,the reaction time is 8 h,the mass ratio of CP-SiO2 to PEI is 4 ∶1,and the reaction solvent is dimethyl formamide(DMF).The grafted amount of PEI in the QPEI/SiO2 prepared at the above conditions is 14.8%.Compared to the QPEI/SiO2 without methylation,the amount of quaternary ammonium salts in the methylated QPEI/SiO2 was added from 0.96% to 3.37%,and its antimicrobial activities against bacteria and yeast were enhanced obviously.