PE-LD/石蜡复合相变储能材料的制备及性能研究

Preparation and Properties of PE-LD/Paraffin Based Composite Phase Change Energy Storage Materials

以固体石蜡、低密度聚乙烯(PE-LD)为原料,乙烯基三乙氧基硅烷改性的膨胀石墨/硅藻土为填料,过氧化二异丙苯(DCP)为交联剂,制备复合相变储能材料。研究了石蜡含量及改性后硅藻土/膨胀石墨用量对复合材料热稳定性及导热性的影响,探讨了DCP含量对复合相变材料微观结构、力学性能的影响。结果表明,当石蜡含量为60%(质量分数,下同)时,热稳定性良好,相变潜热和相变温度更合适;膨胀石墨及硅藻土的加入对复合相变材料热稳定性均有提升,且无机填料含量为4.6%时达到最大值,膨胀石墨对复合材料热稳定性改良效果强于硅藻土;膨胀石墨的加入对复合相变材料导热性能有所提升,当膨胀石墨含量为4.6%时,热导率为对比样的384.38%;DCP的加入使复合相变材料的力学性能有所增强,且含量在3%时综合性能良好。

A series of composite phase change materials（PCMs）were prepared by using solid paraffin and low-density polyethylene（PE-LD）as raw materials,diatomite/expanded graphite modified with vinyl triethoxysilane as fillers and dicumyl peroxide（DCP）as a crosslinking agent.The effect of contents of paraffin and modified diatomite/expanded graphite on thermal stability and thermal conductivity of the composite PCMs were studied,and the effects of DCP content on their microstructure and mechanical properties were also discussed.The results indicated that the composite PCMs exhibited a good thermal stability at the paraffin loading of 60 wt%,and they also presented proper phase-change latent heat and phase-change temperatures. The addition of expanded graphite and diatomite improved the thermal stability of composite PCM,and an optimum thermal stability was achieved at a content of 4.6 wt%.The thermal enhancement effect was better from expanded graphite than from diatomite.;The addition of 4.6 wt% expanded graphite made the composite PCMs an improvement in thermal conductivity by 384.38 %.The mechanical properties of composite PCMs were enhanced with the addition of DCP,and the composite PCMs achieved optimum overall properties when 3 wt% DCP was added.