彈性導熱墊廣泛應用於電子產品之散熱器，以達到高效之散熱效果。彈性導熱墊由橡膠基材及導熱無機填充料組成，橡膠基質提供導熱墊韌性，而無機填充料能提升導熱墊之導熱係數。為了獲得高導熱係數，需提升填料含量，但其同時降低導熱墊之韌性。本研究中，矽樹脂引入矽橡膠/氮化硼，以提高導熱墊之導熱係數性及韌性。本研究透過水解縮合法合成三種矽膠包括：有機矽樹酯(Mono-Quad, MQ)、乙烯基-有機矽樹脂（Vi-MQT）及鋁-有機矽樹脂（Al-MQT）並探討其性質。本研究透過Vi-MQT及Al-MQT樹脂取代MQ樹脂以改善矽橡膠之性能，其中乙烯基與鋁作為功能性單元使有機矽樹脂具有更高之熱穩定性；MQ樹脂之添加會降低矽樹脂之交聯密度、熱穩定性、拉伸強度及硬度，但其提高矽樹酯之斷裂伸長率； Vi-MQT樹脂之添加會降低矽樹脂之交聯密度、拉伸強度及硬度，但其提高矽樹酯之斷裂伸長率及熱穩定性；Al-MQT樹脂之添加對矽樹脂之交聯密度、拉伸強度及硬度無顯著影響，但其改善矽樹酯之斷裂伸長率並降低了熱穩定性。結果顯示，高填料濃度的h-BN使復合材料的導熱係數提高到3.253 Wm-1K-1，拉伸強度及伸長率分別降低到1.248 MPa及22％，硬度提高到75 Shore A。有機矽樹脂的添加能有效改善複合材料的導熱係數性，MQ、Vi-MQT3及Al-MQT3樹脂的熱導率分別達3.661、3.962及4.817 Wm-1K-1；拉伸強度分別提升至1.274、1.290及1.312 MPa；斷裂伸長率分別提升至125、188及150％；硬度分別降至69,71及72 Shore A。而隨著矽樹脂的添加，複合材料之密度、揮發物含量、阻燃性和體積電阻率無顯著變化。本研究添加有機矽樹脂於彈性導熱墊中，不僅改善複合材料之伸長率（韌性），且能提升彈性導熱墊之導熱係數性。

Elastomeric thermal pads is widely used to support a heat sink for an effective and efficient heat dissipation process. Elastomeric thermal pads are consist of rubber matrix and a thermally conductive filler. Rubber is responsible for flexibility property while filler plays a role in the thermal conductivity property. In order to achieve high thermally conductive rubber, high filler loading is needed, in other words, it will sacrifice the flexibility. In this study, a silicone resin introduced in silicone rubber/boron nitride (h-BN) composite to enhance the thermal conductivity with acceptable flexibility property. Three kinds of silicone resin; MQ, vinyl-silicone resin (Vi-MQT) and aluminum-silicone resin (Al-MQT) were synthesized using hydrolysis-polycondensation method and used as a modifier. Additional the functional unit yielded the low molecular weight silicone resin with higher thermal stability. Incorporation of MQ resin reduced the crosslink density, thermal stability, tensile strength and hardness of silicone resin while it improved the elongation property. Replacing MQ resin with Vi-MQT and Al-MQT resin improved the properties of silicone rubber. Addition Vi-MQT resin reduced the crosslink density, tensile strength and hardness while it improved the elongation and thermal stability. Addition Al-MQT resin did not give significant effect to the crosslink density, tensile strength and hardness while it improved the elongation and reduced the thermal stability. High filler concentration of h-BN enhanced the thermal conductivity of composite up to 3.253 W m-1 K-1, reduced the tensile strength and elongation until 1.248 MPa and 22%, respectively, and increased hardness until 75 shore A. Addition of silicone resin improved the thermal conductivity of composites, up to 3.661, 3.962 and 4.817 W m-1 K-1 for MQ, Vi-MQT3 and Al-MQT3 resin, respectively. The tensile strength also improved up to 1.274, 1.290 and 1.312 MPa for MQ, Vi-MQT3 and Al-MQT3 resin, respectively. The elongation at break increased to 125, 188 and 150% with the addition of MQ, Vi-MQT3 and Al-MQT3 resin, respectively. The hardness of composite reduced to 69, 71 and 72 shore A for the addition of MQ, Vi-MQT3 and Al-MQT3 resin, respectively. The density, volatile content, flame resistance and volume resistivity did not significantly change with the addition of silicone resin. It can be concluded that the addition of silicone resin not only improved the elongation (flexibility) but also the thermal conductivity of the composite.

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