有机蒙脱石的制备新方法及性能表征

四甲基氯化铵(TMA)、十六烷基三甲基溴化铵(CTAB)、双氯乙酸丙二醇酯基双十二烷基四甲基氯化二铵(双子季铵盐GQAS)作为钠基蒙脱石(Na-MMT)的改性剂,分别采用一次插层法和两次插层法对Na-MMT进行有机化改性.X射线衍射(XRD)测试表明,Na-MMT的层间距(d001)值随着改性剂碳链长度的增长而增大,采用一次插层法时,d001值依次由Na-MMT的1.30nm增大至1.34nm、2.89nm和3.72nm,而采用两次插层法时(第一次用TMA,第二次用双子季铵盐插层)OMMT的d001值增大至3.99nm.热重分析(TGA)表明Na-MMT的失重率为13.4%,双子季铵盐一次插层的有机MMT(OMMT)的失重率为40.5%,而用TMA第一次插层,双子季铵盐第二次插层的OMMT的失重率为49.8%.傅里叶变换红外光谱(FT-IR)同样证实采用两次插层法,MMT层间吸附的阳离子与有机阳离子的交换更彻底.用双子季铵盐作为改性剂、通过两次插层法制备OMMT,鲜见文献报道.

New Method about the Preparation and Property Characterization of Organic-montmorillonite

Tetramethyl ammonium chloride(TMA),hexadecyl trimethyl ammonium bromide(CTAB) and bi-chloroacetic acid propylene glvcol ester bi-dodecyl tetramethyl bi-ammonium chloride(gemini quaternary ammonium salt,abbreviate to GQAS) were applied to modifying agent of Na-montmorillonites(Na-MMT),Na-MMT was modified by means of one and two times intercalated respectively.The results of X-ray diffraction(XRD) show that interlayer space(d001) of Na-MMT enhanced with the increasing of carbon chain long of the modifying agent,when one time intercalated way was used,the d001 value of Na-MMT increased from 1.30nm(Na-MMT) to 1.34nm for TMA,2.89nm for CTAB and 3.72nm for GQAS.When two times intercalated methods were applied(TMA intercalated first and GQAS second),however,the d001 value of Na-MMT increased to 3.99nm.Thermogravimetric analysis(TGA) indicates the ratio of weight loss is 13.4% for Na-MMT,40.5% for OMMT with one time intercalated,49.8% for OMMT with two times intercalated.Fourier transform infrared spectroscopy also confirms the exchange is more thoroughly between the cations adsorbed in interlayer of Na-MMT and the organic cations with two times intercalated methods.It is rarely found preparing OMMT by two times intercalated applying TMA and GQAS.