摘要
以具有层状硅酸盐结构的累托石(REC)为主体,以烷基季铵盐为改性剂合成了有机累托石(OREC),以有机累托石和环氧树脂复合,制备出纳米复合材料。累托石含量在0.8wt.% 时,纳米复合材料具有最佳力学和热学性能,冲击强度增加到65.6 kJm-2,断裂伸长率从4.7 %增加到20.2 %,玻璃化转变温度提高到 197.9 ℃。用X-小角衍射法、透射电镜和红外吸收光谱研究了材料的微观结构,XRD 衍射图显示,未经处理REC 的层间距d001 = 2. 2 nm,经有机改性后,累托石片层间距扩大到2.8 nm,与环氧树脂复合后,其层间距扩大到4.2 nm 左右,FT-IR图显示,有机累托石中出现十六胺的特征吸收峰,TEM照片显示该复合材料是一种纳米复合材料。
The synthesis of organic rectorite (OREC) is studied by using quaternary ammonium bromine salt with rectorite (REC), and epoxy resin nanocomposites have been further prepared by dispersing organically modified rectorite in a kind of epoxy resin. Mechanical and thermal tests show that the properties of nanocomposites containing 0.8% (weight) of rectorite have been significantly improved in terms of the impact strength (up to 65.6 kJ(.)m(-2)), breaking elongation (rising from 4.7% to 20.2%) and glass transition temperature (up to 28 degreesC) compared to the neat epoxy resin. The product was characterized by XRD, TEM and FT-IR. XRD patterns show the layers of interval of unprocessed REC are d001 = 2.22 nm, while those of organo-rectorite expand to 2.81 nm after organic modification. The d001 basal spacing of organo-rectorite rises from 2.81 to 4.2 nm after polymerization. FT-IR spectra suggest the characteristic absorption of hexadecylamine in the organo-rectorite, and TEM have proved that the composite is a kind of nano-composite. The results indicate that the intercalated and exfoliated structures were observed simultaneously, and it is also found that the rectorite with low clay contents has better dispersion behavior and higher degree of clay exfoliation compared to that. with high clay contents. FT-IR spectra show the reaction between rectorite and epoxy matrix. High surface area and reactivity performance of rectorite nano layers are the reasons for improving the properties of nanocomposites.
基金
国家自然科学基金(50003005)
湖北省科技厅科技资助项目(024660404)
