Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: Thermo-mechanical and Light Transmittance of Silica Diffusant Filled Epoxy Composites | Journal of Physical Science Vol. 21 1 93-107 2010 93 Thermo-mechanical and Light Transmittance of Silica Diffusant Filled Epoxy Composites Lim Wei Chin1 Huong Ling Hung2 and Chow Wen Shyang1 1School of Materials and Mineral Resources Engineering Universiti Sains Malaysia Engineering Campus 14300 Nibong Tebal Pulau Pinang Malaysia 2Oriem Technology Sdn Bhd Plot 25 Bayan Lepas Industrial Estate Non-FTZ Phase 4 11900 Bayan Lepas Pulau Pinang Malaysia Corresponding author chowwenshyang@ Abstract Epoxy ternary blends DCN were prepared by mixing diglycidyl ether bisphenol A DGEBA cycloaliphatic epoxy and novolac epoxy. The silica diffusants were prepared by the addition of spherical silica SS into epoxy blends. The thermal properties of the epoxy composites were characterised using a thermo-mechanical analyser TMA a differential scanning calorimeter DSC and a dynamic mechanical analyser DMA . It was found that the storage modulus of the epoxy was increased in the presence of SS diffusants. However the coefficient of thermal expansion CTE and the glass transition temperature Tg of the epoxy ternary blends was reduced by the addition of SS diffusants which was because the expansion of the epoxy matrix was constrained in the presence of silica fillers. The UV Vis spectroscopy results demonstrated that the percentage of transmittance of epoxy was decreased by the incorporation of the silica diffusant. Keywords polymer composites thermal properties light-emitting diodes LED epoxy blends silica Abstrak Adunan ternari epoksi DCN disediakan dengan pencampuran diglicidil eter bisfenol A DGEBA epoksi silkoalifatik dan epoksi novolak. Difusan silika disediakan dengan penambahan silika sfera SS ke dalam adunan epoksi. Sifat-sifat terma bagi komposit epoksi dikaji dengan menggunakan penganalisis mekanik haba TMA kalorimetri pengimbasan pembezaan DSC dan penganalisis mekanik dinamik DMA . Modulus simpanan bagi epoksi telah ditingkatkan dengan kehadiran difusan SS. Walau .
