کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7056605 1458053 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A molecular dynamics study on thermal conductivity of thin epoxy polymer sandwiched between alumina fillers in heat-dissipation composite material
ترجمه فارسی عنوان
مطالعه دینامیک مولکولی بر روی هدایت حرارتی پلیمر اپوکسی نازک ساندویچ بین پرکننده های آلومینا در مواد کامپوزیت گرمازدایی
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
چکیده انگلیسی
The composite of epoxy polymers and α-alumina fillers is used as a heat dissipation material. The fillers often agglomerate with nanometer-depth polymers sandwiched in between. We address theoretically the effective thermal conductivity of such a filler-polymer-filler system. The non-equilibrium molecular dynamics simulation is performed to obtain the effective thermal conductivity of the system, in which bisphenol-A (bisA) epoxy polymer sub-system with depth 14-70 Å is inserted between two α-alumina slabs. Effects of surface-coupling (SC) agent are also investigated by adding model molecules to the polymer sub-system. For smaller polymer-depth cases, the effective thermal conductivity is determined essentially by the interfacial thermal conductance that relates to the temperature-gaps at the interfaces. We find for the interfacial thermal conductance that: (i) it is decreased by decreasing the polymer depth toward the chain length of a single bisA molecule, and (ii) it is increased by adding the SC molecules to the polymer sub-system. Combining separate simulation analyses, we show that the (i) results from effectively weakened interaction between a bisA molecule and two α-alumina slabs due to the orientation constraint on the bisA molecule by the slabs. Reasons of the (ii) are enhancement of the following three quantities by addition of the SC molecules: the phonon population of the bisA molecules at those frequencies corresponding to that of acoustic phonons of α-alumina, the phonon transmission coefficient from the α-alumina slab to the polymer sub-system for the transverse acoustic phonon, and the group velocity of the transverse acoustic phonon in the polymer sub-system.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 89, October 2015, Pages 714-723
نویسندگان
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