Simultaneous electrical and rheological measurements on conductive polymer composites under elongation

更新建议关注的导电聚合物复合材料（CPC）的熔体的伸长率的同时电气和流变测量。这些测量是最近在原始研究项目的框架内开发的。导电聚合物复合材料的电性能由复合材料加工过程中形成的颗粒结构决定。考虑到拉伸流动涉及许多熔融加工技术，在熔融状态下拉伸下的颗粒结构行为的知识和理解对于生产具有平衡的电性能和加工性能的CPC至关重要。该项目的第一个目的是研究导电颗粒结构在松弛和恢复模式下伸长后的行为。从实践的角度来看，这项研究是重要的，因为松弛/恢复步骤总是发生在熔融加工后，从而影响最终产品的导电性。此外，同时进行的电流和流变测量可以帮助理解填充聚合物系统的拉伸流变学中观察到的效应的起源。与综合颗粒结构、聚合物-颗粒相互作用和聚合物基体的影响的流变学量相反，电测量仅反映颗粒结构的变化。因此，同时拉伸实验允许人们决定在何种程度上是流动引起的颗粒结构的变化负责的应变变薄行为，在伸长或减少的弹性引入聚合物基质中的填料的结合引起的流动限制。该项目的第二个目标是对上述关于填料浓度、温度和伸长条件的影响进行系统研究。

The renewal proposal concerns with simultaneous electrical and rheological measurements in elongation on melts of conductive polymer composites (CPC). These measurements were developed recently in the frame of the original research project. The electrical properties of conductive polymer composites are governed by the particle structures which are formed during the processing of the composite. Taking into account that the elongational flow is involved in many melt processing technologies, the knowledge and the understanding of particle structures behaviour under elongation in the molten state are crucial in production of CPC with balanced electrical and processing properties. The first aim of the project is to investigate the behaviour of conductive particle structures after elongation in relaxation and recovery mode. This study is important from the practical point of view, as the relaxation/recovery step occurs always after melt processing and, thus, influences the electrical conductivity of the final product. Moreover, the simultaneous electrical and rheological measurements can help in understanding of the origins of the effects observed in elongational rheology of filled polymer systems. Contrary to the rheological quantities integrating the effects of particle structures, polymer-particles interactions and polymer matrix, the electrical measurements reflect the changes in the particle structures only. Therefore, simultaneous elongational experiments allows one to decide to which extent are the flow-induced changes in particle structures responsible for the strain thinning behaviour, the flow restrictions in elongation or reduction of the elasticity induced by incorporation of the filler in the polymer matrix. The second aim of the project proposed is to perform systematic studies of the effects mentioned above with respect to filler concentration, temperature and conditions of elongation.