海泡石的活化对湿法制备天然橡胶复合材料性能的影响

Effect of Sepiolite Activation on the Properties of Natural Rubber Composites Prepared byWet Mixing Process

为提升海泡石补强橡胶的应用效果,首先采用有机酸活化制备高活性海泡石(MSep);比表面积、X射线衍射和光电子能谱测试结果表明,MSep的晶体结构完整,比表面积和表面活性明显增强;借助橡胶加工分析仪、扫描电镜和动态力学热分析等方法研究了经湿法乳液混合制备的不同活性及用量的海泡石/天然橡胶复合材料的结构与性能。结果表明,复合材料中的MSep分散性较好,界面相互作用增强;在MSep用量小于30 phr时,随用量增多,拉伸强度和300%定伸应力等逐渐提升,硫化效率则逐渐降低;MSep用量过多时,受填料聚集的影响,综合补强性能下降;此外,随海泡石用量的增多,复合材料储能模量逐渐增大,损耗因子最大值逐渐减小。

To enhance the application effectiveness of sepiolite reinforcement in rubber,organic acid activation was employed to prepare high-activity sepiolite,denoted as MSep.Test results from specific surface area measurements,XRD and XPS confirm the structural integrity of MSep,with a significant increase in specific surface area and surface activity.Utilizing a range of analytical techniques,including RPA,SEM and DMA,etc,the structure and properties of sepiolite/natural rubber composite materials prepared through latex compounding method were investigated,with varying levels of MSep activity and dosage.The results indicate that within the composite materials,MSep exhibits favorable dispersion and strengthens interfacial interactions.When the MSep dosage is less than 30 phr(parts per hundred rubber),increasing the dosage leads to gradual enhancement in properties such as tensile strength and 300%elongation stress,while the vulcanization efficiency progressively diminishes.Excessive MSep dosage,influenced by filler aggregation,results in a decrease in comprehensive reinforcement performance.Furthermore,with an increase in sepiolite dosage,the storage modulus of the composite materials gradually increases,while the maximum of tanδgradually decreases.