Preparation of low-density polyethylene/low-temperature expandable graphite composites with high thermal conductivity by an in situ expansion melt blending process
Preparation of low-density polyethylene/low-temperature expandable graphite composites with high thermal conductivity by an in situ expansion melt blending process
复制标题
DOI：
10.1016/j.matdes.2013.05.056
复制
发表时间：
2013-12
影响因子：
8.4
通讯作者：
Hejun Wu;Canhui Lu;Wei Zhang;Xinxing Zhang
中科院分区：
文献类型：
--
作者：
Hejun Wu;Canhui Lu;Wei Zhang;Xinxing Zhang
提出了一种低成本、易于批量生产的低密度聚乙烯(LDPE)/低温可膨胀石墨（LTEG）复合材料的原位膨胀熔融共混制备方法。在加工过程中，LTEGs被扩展并分层成石墨多层和石墨纳米片，从而协同作用在复合材料中创造了更多的导热路径，从而大大提高了导热性。与纯LDPE相比，当LTEG负荷为60%时，复合材料的导热系数提高了23倍，从0.47 W/mK增加到11.28 W/mK。LTEG的掺入降低了LDPE的熔融温度和结晶度。电导率和流变性测量的渗透阈值在约8 vol%的LTEG加载时被观察到。与纯LDPE相比，LDPE/LTEG复合材料具有更好的热稳定性。
A facile strategy with the advantages of low cost and ease of mass production was presented to prepare low-density polyethylene (LDPE)/low-temperature expandable graphite (LTEG) composites with relatively high thermal conductivity by an in situ expansion melt blending process. LTEGs were expanded and delaminated into graphite multi-layers and graphite nanoplatelets during processing which synergistically created more thermo-conducting paths in the composites and hence led to great improvements in thermal conductivity. Thermal conductivity of the composite with 60 wt% of LTEG loading was increased by 23 times as compared to the pure LDPE, increasing from 0.47 to 11.28 W/mK. The incorporation of LTEG decreased the melting temperature and the degree of crystallinity of LDPE. Percolation threshold of both the electrical conductivity and rheological measurements was observed at about 8 vol% of LTEG loading. Moreover, the LDPE/LTEG composites showed better thermal stability compared to the pure LDPE.