改性高岭土对丁苯橡胶的增强和阻隔作用研究

REINFORCEMENT AND BARRIER FUNCTION OF MODIFIED KAOLIN ON STYRENE-BUTADIENE RUBBER

利用化学改性的高岭土（MK）和沉淀白碳黑（PS）作为增强剂，与丁苯橡胶（SBR）进行熔融共混和乳液共混制备橡胶复合材料，并对其力学性能、气体阻隔性能、热稳定性能以及微观结构进行分析测试，结果表明：改性高岭土在丁苯橡胶基俸中达到了纳米水平的均匀分散，片层多呈平行定向排列，对橡胶大分子具有圈闭限制作用，明显改善了复合材料的力学性能和热稳定性能；另外，高岭石片层的不可穿透性，有效延长了气体分子在橡胶中的渗透路径，复合材料的透气率降低了40％～60％，气体阻隔性能得到了显著的提高；而且，片状结构的改性高岭土比球状结构的白碳黑更真有阻隔优势。

One modified kaolin （MK） and precipitated silica （PS） were introduced into the styrene-butadiene rubber （SBR） to prepare rubber composites by melt blending and latex blending. The mechanical properties, gas barrier properties, thermal stability and microstructure of SBR composites were investigated. Results showed that MK was well dispersed in the nano-scale and was on parallel arrangement clearly in the rubber matrix. The kaolin sheets trapped the rubber molecular chains and confined its free movement, which improved the mechanical properties and thermal stability of SBR composites markedly. The impervious kaolin sheets prolonged the pene- trating path of gas molecules in the rubber composites, which reduced the permeability about 40 -60% and improved the gas barrier property of the rubber composite effectively. Moreover,the plate-like MK provided better barrier capability than the spherical PS.