平衡溶胀法研究谷氨酸二硫代氨基甲酸镧对SBR/SiO2复合材料界面作用的影响

通过合成一种含有二硫代羧基,羧基和镧离子的新型稀土促进剂——谷氨酸二硫代氨基甲酸镧(简称La-GDTC),并利用平衡溶胀法研究了La-GDTC对丁苯橡胶(SBR)/SiO2复合材料界面作用的影响.交联密度测试表明,SiO2的加入能够有效提高SBR/La-GDTC/SiO2复合材料的交联密度;而SBR/La-GDTC/S...

STUDIES ON THE INFLUENCE OF LANTHANUM GLUTAMIC DITHIOCARBAMATE ON THE INTERFACIAL REINFORNCEMENT OF SBR/SiO2 COMPOSITES BY SWELLING EQUILIBRIUM TEST

A new rubber functional agent with dithiocarbamate group,carboxyl groups and lanthanum ion,called lanthanum glutamic dithiocarbamate(La-GDTC),was synthesized and its chemical structure was characterized by FTIR and element analysis.The interfacial interactions of SBR/La-GDTC/SiO2composites were measured by toluene swelling-equilibrium test under room temperature.The crosslinking density data of SBR/La-GDTC/SiO2 composites turned out,with the increasing loading of silica content,that the crosslinking density evolved to a high extent considerably,without respect to the obstructed effect of the silica particles on sulfur crosslink reaction.The swollen Gibbs free energy parameters of the composites ΔG decreased dramatically and ΔS increased obviously,both of which interpreted that the chemistry environment of the silica particles in the rubber hybrid composites changed to some extent,leading to a more heterogeneous network existed in the composites and a different chemical bonding structure between the rubber matrix and inorganic particles.Also,the interphase interaction parameter C,obtained from Kraus equations,was the value of 2.02 and verified the reinforcement between SBR and silica particles via the hydrogen bonds and chemical bonds between the La-GDTC and silica particles.The tensile strength,elongation at break and tear strength all pointed out that the mechanical properties of the La-GDTC system were much higher than those of the ZDC system.Also,in the SEM photographs,well-dispersed silica fine particles and more fluctuated surface of the La-GDTC-4 were attained,however,the silica clusters aggregation and smooth surface of the fracture were observed in the ZDC-4,implying that the interface interaction between the SBR/silica particles of the La-GDTC system was much stronger than that of the ZDC system.Based on the fore-mentioned experimental observation,an interphase structure between the rubber matrix and the inorganic particles was discussed.