黏土/SBR纳米复合材料的加工性能

Processing property of clay/SBR nanocomposites

采用橡胶加工分析仪(RPA)和孟山都毛细管流变仪研究了黏土/SBR纳米复合材料的Payne效应和流变性能,并同炭黑(N330)与微米级黏土橡胶复合材料进行了对比。结果表明,黏土/SBR纳米复合材料的流变规律与传统填充体系的流变规律类似,其弹性模量均随着填料用量的增加而增大,填料之间形成拟网络结构,在加工过程中,具有Payne效应;纳米分散的黏土具有更大的宽厚比和各向异性,对橡胶分子链限制作用更强,网构化程度更高,在相同的应变和频率下,与炭黑和黏土直接混炼填充SBR体系相比,黏土/SBR纳米复合材料的弹性模量更高;纳米化程度越高,网构化程度也越高;在相同的毛细管剪切速率下,黏土/SBR纳米复合胶料的黏度略高于炭黑体系;在黏土/SBR纳米复合胶料中,加入界面剂改善界面强度和改进工艺增加增强单元数目,胶料弹性模量提高;黏土/SBR纳米复合胶料具有出口膨胀小,吃粉快,挺性好的良好加工性能。

By rubber process analysis(RPA) and Monsanto capillary rheometer the Payne effect and processing rheologic property of the clay/SBR nanocomposite(NC) were investigated.Carbon black(N330)/SBR compound and micron clay/SBR compound were also discussed as a comparison.The experiment results indicated that the modulus of the clay/SBR NC increased remarkably with the increase of the filler loading and there were Payne effect in the compounds attributed to the network of filler. It had the same trend as the N 330/SBR and micron clay/SBR compounds. With the higher ratio and anisotropy the dispersed clay could restrain strongly the rubber molecule chain movement,which resulted in its highest modulus among three compounds in our research when the same strain and frequency were loaded.Moreover, the viscosity of the NC material was higher than that of compound with the same load of CB at the same shear rates.By adding the interface agent and improving the processing conditions the amount of reinforcement cells in clay/SBR NC were mounted up,and this made the NC material higher module.The processing property of clay/SBR NC was better with small extrusion swelling, easy blending and stable dimension.