亲水丙烯酸酯单体对乳液聚合法制备聚（苯乙烯-丙烯酸酯）／OMMT／SiO2纳米复合材料性能影响

Effects of hydrophilic monomer on the properties of poly（styrene-acrylate）/ montmorillonite/nano-SiO2 nanocomposite by emulsion polymerization

以十六烷基三甲基溴化铵（CTAB）改性钠基蒙脱土，得到有机蒙脱土（OMMT），分别以亲水性甲基丙烯酸β羟乙酯（HEMA）、甲基丙烯酸（MA）和丙烯酸（AA）为共聚单体，采用乳液聚合法制备了聚（苯乙烯-丙烯酸酯）／OMMT／SiO2纳米复合材料，研究了亲水单体种类及用量对复合材料性能的影响。通过红外光谱（IR）、X射线衍射（XRD）、差示扫描量热（DSC）和热重分析（TG）等分析方法对复合材料进行了表征。结果表明，聚合物中蒙脱土片层处于剥离状态无规地分散在聚合物基体中；使用HEMA制得的聚（苯乙烯-丙烯酸酯）／OMMT／SiO2纳米复合材料耐热性能优于MA和AA，适量的HEMA可以提高复合材料耐热性能。

The montmorillonite was modified by cetyltrimethyl ammonium bromide which was designated as OMMT. Poly（styrene-acrylate）/OMMT/Nano-SiO2 nacomposites were synthesized by emulsion polymerization. The effects of the hydrophilic monomer level and type on the properties of nanocomposites were studied. The composites were characterized by fourier transform infrared spectroscope（FTIR）, differential scanning calorimetry （DSC）, thermogravimetry （TG） and X-ray diffraction（XRD）. It was found that the OMMT layers were exfoliated and dispersed in the polymer matrix randomly. When the styrene/hydrophilic monomer ratio is 44 ： 1, thermal properties of the nanocomposite which was prepared with hydroxyethyl methacrylate （HEMA） is better than that with acrylic acid and methyl acrylate, and the thermal properties decreased with the increase of level of HEMA.