The accurate determination of the elongation at breakεb of sheath materials for rail transit cables helps to evaluate their application performance.Therefore,research and analysis have been conducted on the sample preparation method for testingεb of thermoplastic high flame retardant polyolefin sheathing materials.Comparison of εb test data obtained by four sample preparation methods(first plastic refining followed by molding,direct granular molding,extrusion,and first extrusion followed by molding),it is found that theεb test data of the sample prepared by molding method according to the standards GB/T 32129-2015 and JB/T 10707-2007 are relatively scattered and theεb test results are relatively low,while theεb test data of the sample prepared by extrusion method are more centralized,stable,and reliable.At the same time,comparing the above test results with theεb test data of high-temperature treated samples according to the standard GB/T 2951.11-2008,it is found that high-temperature treatment can improve the dispersion ofεb test data for thermoplastic high flame retardant polyolefin sheathing materials,but has no significant impact on the εb test data average of samples prepared by different sample preparation methods.
关键词
高阻燃聚烯烃/电缆护套料/断裂伸长率/模压法/挤塑法/高温处理
Key words
high flame retardant polyolefin/cable sheath material/elongation at break/molding method/extrusion method/high temperature processing
万方数据