Anisotropic thermal conductivity in sheared polypropylene

被引：0
作者：
Shao Cong Dai
Roger I. Tanner
机构：
[1] The University of Sydney,Rheology Research Group, School of Aerospace, Mechanical and Mechatronic Engineering
来源：
Rheologica Acta | 2006年 / 45卷
关键词：
Thermal conductivity; Polypropylene; Anisotropy;
D O I：
暂无
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学科分类号：
摘要：
We discuss the anisotropy of the thermal conductivity tensor in polymer flow in this paper. Isotactic polypropylene (iPP) specimens were deformed by injection moulding at high shear rates and by steady shear at low shear rates, and were then quenched. The thermal conductivities parallel and perpendicular to the shear direction were measured using modulated differential scanning calorimetry (MDSC) in accordance with the ASTM E1952-01. The measured results showed that the thermal conductivity of the sheared polymer was anisotropic with an increase in the shear direction. The thermal conductivity can be regarded as varying either with the strain or the stress, as suggested by Van den Brule (1989). In addition to the Van den Brule mechanism, crystallization during flow also changes the thermal conductivity and this effect may often be dominant. Suggestions for procedures in processing computations, based on both effects, are given.
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页码：228 / 238
页数：10
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