季铵盐改性蒙脱石的超结构及其抗菌性能

为研究季铵盐改性对蒙脱石的结构及抗菌性能的影响,分别采用十八烷基三甲基氯化铵（OTAC）和双十八烷基二甲基氯化铵（DODAC）对蒙脱石进行插层改性,并分析了蒙脱石的d001层间距及抗菌性能随季铵盐用量变化的规律.蒙脱石的d001层间距先随季铵盐用量的增加而增大；当OTAC与蒙脱石的质量比超过35%或DODAC与蒙脱石的质量比超过15%时,其d001层间距开始略微下降,同时出现季铵盐以不同倾斜角排列的层间超结构现象.在水分散体系中,改性蒙脱石的抗菌性能先随季铵盐用量的增大而上升；当其出现超结构后,由于蒙脱石及季铵盐与细菌的接触几率受到限制,其抗菌性能开始急剧下降.在干燥条件下超结构对蒙脱石的抗菌性能影响甚微,经不同用量季铵盐改性的蒙脱石都具有极佳的抗霉菌性能.

Superstructure of quaternary ammonium modified montmorillonite and its antibacterial properties

To investigate the effects of quaternary ammonium (QA) modification on the structure and antibacterial activities of montmorillonite (MMT), octadecyl trimethyl ammonium chloride (OTAC) and dioctadecyl dimethyl ammonium chloride (DODAC) were separately intercalated into MMT, and the variations of the d001 spacing and antibacterial activities of MMT were investigated as a function of QA dosage. The d001 spacing of MMT increases with the dosage of OTAC and DODAC firstly. When the mass ratio of OTAC/MMT is greater than 35% or the mass ratio of DODAC/MMT is greater than 15%, the d001 spacing starts to decline slightly. Meanwhile, OTAC or DODAC arranges in different angles in the interlayer of MMT and forms superstructures. In the water dispersion system, the antibacterial activity of MMT increases with the QA dosage firstly. Because superstructures will restrict the contacting between bacteria and MMT or QA, the antibacterial activity decreases sharply when the superstructure appears. Under drying conditions, however, the superstructure affects little on the anti mould ability of MMT and all the MMTs modified by various kinds and dosages of QA show excellent anti mould activities.