导电高分子复合材料表面微裂纹性褶皱结构的构筑及力敏行为研究

Due to excellent mechanical and electrical properties, good flexibility, conductive polymer composites (CPCs) have received widespread attentions from researchers as a new type of flexible stress sensitive materials. In this project, polydimethylsiloxane and AgNW/CB will be selected as polymer matrix and conductive fillers, methyl cellulose will be used as dispersant and adhesion agent, then the PDMS/AgNW/CB conductive polymer composites with microcracked folding structural conductive coating will be using the thermal treating and prestretch-release techniques. Moreover, the synergistic effect between AgNW and CB will also be utilized to prepare flexible CPCs based stress sensitive materials with high sensitivity, high resolution and wide response range. The following issues will be mainly stuided: the variation of the microstructure of conductive coating and its influence on the stress sensitive behaivior under different stress conditions; the influence of the synergistic effect between conductive fillers on the stress sensitive behavior; constructing a mathematical model of the microstructure variation of conductive coating under external stress to fulfill the numerical prediction of stress sensitive behavior. This study will provide a technical route and theoretical guidance for the preparation of hig-performance flexible stress sensitive sensor.

由于优良的力学和电学特性、柔韧性好等特点，导电高分子复合材料（Conductive Polymer Composites，CPCs）作为一种新型柔性力敏传感材料受到研究者的广泛关注。本项目以柔性聚二甲基硅氧烷（PDMS）为高分子基体，银纳米线（AgNW）和炭黑（CB）为导电填料，甲基纤维素为分散剂和粘合剂，采用“热处理”和“释放预拉伸”工艺制备了表面导电涂层含“微裂纹性褶皱”结构的PDMS/AgNW/CB导电复合材料；同时借助AgNW与CB间的协同效应，以期获得具有高灵敏度、高分辨率和宽响应范围的柔性CPCs传感材料。重点研究CPCs在不同应力条件下导电涂层微结构的变化及其对力敏行为影响；导电填料间的协同效应对力敏行为影响；构建外力作用下导电涂层微结构演变的数理模型，实现对材料力敏行为的数值预测。本研究将为制备高性能柔性力敏传感器提供一定技术路线和理论指导。

随着可穿戴智能设备的快速发展，高性能柔性力敏传感材料作为其核心部件受到研究人员的广泛关注。本项目主要是基于导电高分子纳米复合材料（CPCs）优异的柔性、可加工性、结构可设计性及特殊的力敏响应特性，通过特殊导电网络（微裂纹结构、协同效应、褶皱结构）的构筑及优化设计，实现CPCs力敏传感器的高性能化和可控化制备。系统研究了微裂纹结构对拉伸、压缩及弯曲应变传感器的力敏传感响应性能的影响，深入分析了其对传感器超低应变探测限（0.1%）的内在作用机制；分别通过改变导电涂层的组分比例和利用不同维数导电填料间的协调效应，实现了导电涂层微裂纹结构的可控构筑，最终可有效调控CPCs力敏传感响应性能，并深入探讨了相应的调控机理；在微裂纹结构的基础上，通过构筑褶皱结构实现了材料的综合力敏传感响应性能进一步提升，并研究了两种微结构联用对传感器力敏响应性能的作用机制；为提高CPCs力敏传感器的实用性能，通过结构和组分优化设计，获得了具有耐高低温、自清洁的新型力敏传感器，有效的拓展了该类传感器的应用前景。该研究为新型高性能柔性力敏传感器的设计及制备提供了有效的技术路线和理论指导，在新一代航天服可穿戴外骨骼智能控制方面具有巨大的应用潜力。项目共发表第一标注资助学术SCI论文14篇，获得授权发明专利1项，毕业博士生1人，毕业硕士生4人。