ESBR/SiO2胶乳的破乳动力学及复合材料性能

Flocculation Behavior and Demulsification Dynamics of ESBR/SiO2 Emulsion and Properties of ESBR/SiO2 Composites

系统探究了NaCl和CaCl2溶液絮凝乳聚丁苯橡胶/白炭黑(ESBR/SiO2)胶乳的行为及破乳动力学,考察了硅烷偶联剂TESPT和NXT对复合材料力学性能、动态黏弹性能和流变性能的影响。研究发现,NaCl溶液破乳呈现匀速破乳、加速破乳的过程,而CaCl2溶液破乳则呈现匀速破乳、加速破乳和减速破乳3个阶段。白炭黑粒子对体系破乳效应的影响存在差异,这主要是因为二价Ca^2+对电荷中和能力比一价Na^+高,导致白炭黑的成核中心作用不同。此外,发现硅烷偶联剂NXT使白炭黑在橡胶基体中的分散性显著提高,使其复合材料的硫化性能得到优化,力学性能明显提高,在保持抗湿滑性能时滚动阻力明显降低。

In this study,the flocculation behavior and demulsification kinetics of ESBR/SiO2 emulsion were investigated by the addition of NaCl and CaCl2 solution and effects of TESPT and NXT silane coupling agents on the mechanical properties,dynamic viscoelastic properties and rheological properties of the composites were probed.It is found that a constant and then accelerated process is displayed in the system of NaCl solution while another retarded process is shown in the system of CaCl2 solution,and the demulsification effects of silica in different systems is significantly different.This can be ascribed to the different ability between Ca^2+ and Na^+ for demulsification,leading to different behaviors in the nucleation center of silica.In addition,it is found that the tensile strength and elongation at break of the NXT modified silica filled composites are significantly enhanced,and the rolling resistance is significantly reduced while the wet skid resistance is maintained.