PTFE /nano-SiO2 composites were prepared and the effect of nano-SiO2 by surface pre-treatment of nano-SiO2 ;selecting special macromolecule dispersing agent and master batch manufacturing technogy.The results showed the filling of nano-SiO2 decreased the breaking elongation of PTFE composites,but increased the tensile strength and the hardness of the materical.When the content of nano-SiO2 was 7% by mass, PTFE / nano-SiO2 composites had good mechanical properties.with the increase of nano-SiO2 content the PTFE composites changed from tuough and plastic into hard brittle material.
运用密度泛函理论方法,在B3LYP/6-31++G**水平上对3,5-二氨基-1,2,4-三唑离子和苦味酸(2,4,6-三硝基苯酚)离子氢键二聚体进行理论计算研究.计算结果表明,该二聚体存在较强的氢键,经过基组重叠误差(BSSE)和零点振动能(ZPE)校正,最稳定二聚体的氢键相互作用能是-127.22 kJ/mol.振动光谱分析,N—H…O氢键的形成使N—H键的伸缩振动频率减小,振动强度增大.热力学性质研究显示,在室温和标准压力下氢键二聚体的形成是放热自发的过程.化合物C2N5H+6C6N3O7H-2的标准摩尔生成焓△f H m与标准摩尔生成自由能△f G m分别为-311.89和102.21 kJ/mol.