Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments  

作　　者：Tian-Hao Yang Tong Wu Qiang Fu 

机构地区：[1]State Key Laboratory of Polymer Materials Engineering,College of Polymer Science and Engineering,Sichuan University,Chengdu,610065,China [2]State Key Laboratory of Polymer Materials Engineering,Polymer Research Institute of Sichuan University,Chengdu,610065,China

出　　处：《Chinese Journal of Polymer Science》2024年第4期511-520,共10页高分子科学（英文版）

摘　　要：Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关 键 词：Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment 

分 类 号：TB332[一般工业技术—材料科学与工程] TM24[电气工程—电工理论与新技术]