In-situ polymerization of ethylene with graphene has been previously studied; however, the reported nanocomposites exhibit poor filler dispersion, even at low graphene loadings. In the present work, well dispersed and homogeneous graphene nanoplatelets (GNP)-high density polyethylene (HDPE) nanocomposites were obtained in up to 12.5% weight content of graphene through an in-situ polymerization of ethylene in graphene suspensions. The composites' potential as masterbatches was evaluated by melt mixing them with commercial HDPE. The obtained materials exhibited important physical-mechanical properties increases when compared with those of commercial HDPE. To our knowledge, our materials' GNP concentration (≤0.82 wt.%) is the lowest reported, with the composites showing a 27% increase in their maximum tensile strength and a 41% increase in their flexural modulus when compared with blank HDPE. In addition, Raman spectroscopy and scanning electron microscope (SEM) analyses give evidence of the higher exfoliation degree of GNP obtained in the in-situ ethylene polymerizations.

中文翻译：

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通过原位乙烯聚合获得和评价具有石墨烯纳米片的聚乙烯纳米复合材料

先前已经研究了乙烯与石墨烯的原位聚合；然而，报道的纳米复合材料表现出较差的填料分散性，即使在低石墨烯负载下也是如此。在目前的工作中，通过乙烯在石墨烯悬浮液中的原位聚合，获得了分散良好且均匀的石墨烯纳米片 (GNP)-高密度聚乙烯 (HDPE) 纳米复合材料，其中石墨烯的重量含量高达 12.5%。复合材料作为母料的潜力是通过将它们与商业 HDPE 熔融混合来评估的。与商业 HDPE 相比，所获得的材料表现出重要的物理机械性能增加。据我们所知，我们材料的 GNP 浓度 (≤0.82 wt.%) 是最低的报道，与空白 HDPE 相比，复合材料的最大拉伸强度增加了 27%，弯曲模量增加了 41%。此外，拉曼光谱和扫描电子显微镜 (SEM) 分析表明，在原位乙烯聚合中获得的 GNP 剥离程度更高。