【摘要】 利用Na2 SiO3的改性机理来纯化Na基蒙脱土 ,通过调节体系的pH值及其聚合阴离子的作用 ,使蒙脱土边面带负电荷 ,有效调节蒙脱土在水中的分散状态 ,使其与有机阳离子的交换反应充分进行 ,得到有机蒙脱土的阳离子交换量达 115mmol 10 0 g土 ,并且能均匀分散在甲基丙烯酸甲酯 (MMA)单体中。借助普通的乳液聚合方法 ,制备出PMMA 有机蒙脱土纳米复合材料。复合材料经甲苯抽提、FTIR、XRD、TEM、DSC、TGA等一系列分析方法表征 ,表明有机蒙脱土在PMMA基体中已达到纳米级分散 ,多数已发生剥离 ,而且复合材料的热性能较纯PMMA有很大提高 ,其Tg 和Td 最大分别提高 31.45℃和 42 .13℃。更多还原

【Abstract】 Sodium silicate is used to passivate sodium base montmorillonite(MMT).Moderating the pH value of the system and function of polymerization anions endows MMT with negative charges and controls the dispersion of MMT in water,thus making the exchange reaction of MMT and organic cation complete.Amount of cation exchange of the resultant organo-MMT is up to 115 mmol/100g MMT.It can disperse in MMA evenly.By means of emulsion polymerization, PMMA/organo-MMT nanocomposite was prepared.The composite is extracted by toluene and characterized by FTIR,XRD,TEM,DSC and TGA.Results showed that nano dispersion of organo-MMT in PMMA was achieved and most of it was exfoliated.Thermal performance of the composite was improved greatly compared to pure PMMA.Its glass-transition temperature and degradation temperature reached 30.61 ℃ and 42.13 ℃ respectively.更多还原