Expanded graphite (EG) is introduced into poly(vinylidene fluoride) (PVDF) by melt mixing extrusion with water injection. The results demonstrate that the unfunctionalized EG in composite prepared with water injection exbibits better dispersion than that in the one prepared without water injection due to the promoting role of water during extrusion. Thus, the PVDF/EG composite with loading of 4 wt% prepared by water‐assisted mixing extrusion (WAME) exhibits electrical conductivity of about three orders of magnitude higher than the neat PVDF and one order of magnitude higher than the one prepared without water injection. Comparing to the neat PVDF, the thermal conductivity of the composites prepared with and without water injection is increased by 101.5% and 75.0%, respectively. The introduced EG leads to increased Young’s modulus and tensile strength especially for the composite prepared by WAME. The present work indicates that WAME can promote the dispersion of EG in PVDF matrix without any extra functionalization.

中文翻译：

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通过水助混合挤出添加不经表面改性的膨胀石墨来改善聚偏二氟乙烯的性能

通过熔融混合挤出和注水将膨胀石墨（EG）引入聚偏二氟乙烯（PVDF）中。结果表明，由于水在挤出过程中的促进作用，注水制备的复合材料中未官能化的EG的分散性优于未注水制备的复合物。因此，通过水辅助混合挤压（WAME）制备的负载量为4 wt％的PVDF / EG复合材料的电导率比纯PVDF高约三个数量级，比不注水制备的电导率高一个数量级。 。与纯净的PVDF相比，注射和不注射水制备的复合材料的热导率分别增加了101.5％和75.0％。引入的EG可以提高杨氏模量和拉伸强度，特别是对于WAME制备的复合材料。目前的工作表明WAME可以促进EG在PVDF基质中的分散，而无需任何额外的功能化。