季鏻盐改性蒙脱土的制备及性能

Preparation and property of modified montmorillonites with quaternary phosphonium salts

采用离子交换法将不同的季鏻盐交换到钠基蒙脱土的层间得到改性蒙脱土,并对改性蒙脱土的结构和性能进行了研究。热重量法和X射线衍射分析的结果表明,季鏻盐已插入蒙脱土的层间,并且季鏻盐改性蒙脱土中有机物的热分解起始温度比季铵盐改性蒙脱土的热分解起始温度提高30℃;解吸试验的结果表明,改性蒙脱土中的季鏻盐在水和0.9%NaCl溶液中都很稳定。钠基蒙脱土对金黄色葡萄球菌(S.aereus)和大肠杆菌(E.coli)的最低抑菌浓度均大于2 g/L,而当插入季鏻盐后,其最低抑菌浓度大幅度降低,如十四烷基三丁基季鏻盐改性蒙脱土对S.aereus和E.coli的最低抑菌浓度分别为12.5 mg/L和200.0 mg/L。随着季鏻盐改性蒙脱土浓度的增加和接触时间的延长,改性蒙脱土的抗菌性能增强。

Na-montmorillonite （Na-MMT） was modified with different quaternary phosphonium salts using ion-exchange method, and the structures and property of modified montmorillonite were studied. The results of thermogravimetric analysis and X-ray diffraction show that different quaternary phosphonium salts are intercalated interlayer of montmorillonite, and the onset temperature of decomposition of quaternary phosphonium salts in modified montmorillonite is approximately 30℃ higher than that of quaternary ammonium salts. The result of desorption test of quaternary phosphonium salts from montmorillonite indicates that modified montmorillonite are quite stable. The minimal inhibitory concentration of Na-MMT against Staphylococcus aureus （S. aereus） and Escherichial coli（E, coli） are more than 2 g/L, and that of modified montmorillonite with different quaternary phosphonium salts decreases sharply. For example, the minimal inhibitory concentrations of modified montmorilonite with tributyltetradecyl phosphonium salt （TBTP-MMT） against S. aereus and E. coli are 12.5 mg/L and 200.0 nag/L, respectively. The antimicrobial activity of modified montmorillonite increases with the increase of concentration and contact time,