添加氮化硼及氮化鋁以提升高分子複合材料之熱傳導性質

Abstract

氮化硼 (boron nitride, BN) 具有良好的導熱能力並具備便宜的優勢，因此 BN 在工業界之應用常做為散熱添加劑 (filler) 的無機材料。在上年度的執行中計畫，對於高分子複合材料 (RTV矽膠+BN) 導熱性質的提升研究我們已經取得初步研究成果: 將 BN 混掺於高分子材料 (RTV矽膠) 中的添加量增加時，可以有效的提升高分子複合材料熱傳導性質，其導熱率可達 0.8 W/mK 以上。此外，我們亦使用添加劑 (1,8-diiodooctane) 加入高分子複合材料中促進 BN 無機材料在RTV矽膠中的結晶性，此結果可從 XRD Patterns 獲得證明 BN 的結晶度因使用添加劑 (1,8-diiodooctane)而提高，同時其量測出的熱傳導性質也有相對的提升。 針對本年度的新計畫，我們將使用2 種不同的無機導熱材料 (即氮化硼BN與氮化鋁AlN) 混掺於3 種不同官能基的高分子單體 (環氧基單體、與C=C單體混合Si-H矽膠)，進行不同種類無機及高分子材料的搭配，不同尺寸的無機材料，與不同無機及高分子比例的混摻。針對目前業界所需的封裝特性、熱傳導特性、熱應力、透明度等不同的需求，去做最佳化的探討及研究，透過上述不同參數的調變，加上利用熱傳導分析儀等量測。最後預期此計畫之研究成果，我們將可獲得最佳化的熱傳導、熱應力、透明度、及機械性質的高分子複合材料。

Boron nitride (BN) has good thermal conductive capacities and cheap price, so BN becomes common filler inorganic materials for heat dissipation in the industrial applications. We got some good results from our present project in the past half an year, i.e., “Enhancements of Thermal Conductivities in Polymeric Nano-Composites by Doping Boron Nitride (BN)”. The thermal conductivities of the polymeric composites were enhanced gradually (up to 0.8 W / mK) as BN was added gradually in the polymers (RTV). In addition, the crystallinity of BN in the polymers was increased as the additive (1,8-diiodooctane) was introduced in the polymeric composites, and the XRD patterns prove the crystallinity of BN is proportional to the amounts of 1,8-diiodooctane. Thus, the thermal conductivities of the polymeric composites were improved due to the higher crystallinity of BN induced by the additive (1,8-diiodooctane). In this proposal, we focus on two different inorganic materials (boron nitride BN and aluminum nitride AlN with excellent thermal conductivities) blended with three different kinds of monomers containing various functional groups (including acrylic group, and C=C combined with Si-H groups). Different types and ratios of inoganic materials (boron nitride and aluminum nitride with various sizes) and polymers (containing acrylic group, and C=C, Si-H) were blended to produce various polymeric composites. Therefore, according to the adjustment of previous parameters, polymeric composites can be optimized to possess many different requested merits, such as packaging, thermal conductivity, thermal stress, and transparency, via the following characterization techniques: Thermal conductive equipments. Finally, we expect to obtain polymeric composites with the optimized thermal conductivities, thermal stress, transparency, and mechanical properties. Key Words: Polymer Composites, Hexagonal Boron Nitride, Aluminum Nitride, Heat Dissipation.