界面氢键结合的天然橡胶/改性气相法白炭黑纳米复合材料

用间苯二酚与六亚甲基四胺络合物（RH）对气相法白炭黑进行表面改性，通过混炼和硫化制备了天然橡胶/改性气相法白炭黑（NR/M-silica）纳米复合材料，并通过力学性能测试、交联密度测定、透射电镜、差示扫描量热法、红外光谱和X射线光电子能谱等手段研究了纳米复合材料的结构和性能．结果表明：M-silica对NR硫化胶的补强效果显著优于未改性的气相法白炭黑，当M－silica用量为4～10份时，硫化胶的力学性能最佳；M-silica在橡胶基体中分散良好，硫化胶的交联密度和玻璃化温度提高；在改性剂RH作用下，白炭黑的Si-O键和硅羟基的红外光谱特征吸收峰发生明显的蓝移，且O原子的结合能发生明显的变化，表明白炭黑表面的硅羟基与RH受热后形成的间苯二酚甲醛树脂中的酚羟基之间形成了明显的氢键作用．在上述研究的基础上讨论了RH改性气相法白炭黑补强天然橡胶的机理．

Natural Rubber/Modified Fumed Silica Nanocomposites Containing Interfacial Hydragen Bonds

Fumed-silica surfaces were modified with resorcinol and hexamethylenetetramine complex (RH), and NR/M-silica nanocomposites were prepared in mixing and curing process. Structure and properties of NR/M-silica nanocomposites were investigated by mechanical testing ,cross-linking density determination, transmission electron microscopy(TEM), differential scanning calorimetry(DSC), fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy(XPS). The results showed that M-silica have obvious reinforcement effect on NR vulcanizate. When the contents of modified fumed silica are 4～10％，the comprehensive mechanical properties of NR/M-silica nanocomposite vulcanizates are optimum. M-silica is dispersed in rubber matrix at nanometer scale, and crosslinking density and glass transition temperature of the vulcanizate are increased. The characteristic absorption peaks of Si-O bond and silicon hydroxyl group of fumed silica are obviously shifted to blue wave direction under the effect of modifier RH，and the binding energy of O atom is obviously changed. indicating that the hydrogen bonds form between the silicon hydroxyl groups of fume-silica surfaces and the phenol hydroxyl groups of resorcinol- formaldehyde resin which formed by heating of RH .The reinforcement mechanism of M-silica on natural rubber is discussed according to above results.