A method for continuously analyzing three-dimensional flow, variation of strain components and Young's modulus after gelation during the molding process of thermosetting compounds has been developed. In this analysis, Kamal's model was used to calculate the degree of cure and heat generation. A viscosity model was formulated as a function of temperature and degree of cure. Strain components were calculated by adding the contributions due to curing shrinkage and thermal change. The strain component due to curing shrinkage was modeled as a function of degree of cure. The strain component due to the thermal change was calculated as a function of temperature and the coefficient of linear expansion by considering the glass transition temperature. Young's modulus was calculated as a function of the degree of cure and temperature in relation to the glass transition temperature. These models were integrated using FLOW-3D^® software, which is typically used for multipurpose 3-D flow analysis. Using the newly developed system, the molding process of a diode package was analyzed. The flow behavior in the mold cavity, the changes in the strain components and Young's modulus after gelation were calculated continuously. The proposed method can be utilized for the prediction of residual strain and residual stress in final products caused by flow and curing behavior during the molding process.

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The effects of the compounding of clay nano-particles on the material properties of biodegradable resin composites containing natural fiber products were examined experimentally. Cotton fiber was used as a natural fiber product, and Polycaprolactone (PCL) and Polybutylenesuccinate (PBS) were used as the biodegradable resins. Organic modified clay of the montmorillonite type (OMMT) was used for the nano-particles. The composite preparation was carried out using a twin-screw extruder.
Thermogravimetric analysis (TGA) measurements were carried out in order to examine the thermal characteristics of the composites. The heat-resistance of the composites was further improved by compounding with the OMMT.
Tensile and Izod impact tests were carried out for the material strength evaluations. In both material strength tests, it was found that the reinforcement effect of the cotton fiber decreased with the compounding of the OMMT due to the lubricant effect of the clay nano-particles. Conversely, the Young's modulus of the composites increased with the OMMT. The Young's modulus was also estimated from the Halpin equation modified by Nielsen, and the material strength of each composite was predicted by the assumption of an elastic body model.

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ストレート真空成形現象を市販のブロー解析システム“SIMBLOW”を用いてシミュレートしを、実際のストレート真空成形品の厚み分布測定結果との比較解析を通じて数値シミュレーションの予測精度について検証した。シミュレートにおいては樹脂のレオロジー特性をK-BKZ型構成方程式により表現するとともに、成形現象解析から与えられる解析条件をもとに解析を行った。樹脂のキャラクタリゼーションでは、動的粘弾性測定結果から緩和スペクトルを求めるとともに、K-BKZ構成方程式の物質パラメーターは一軸伸長挙動にフィットする値を試行錯誤的に求めた。ストレート真空成形の数値解析の結果、成形上重視される成形型コーナーの最薄肉部から成形型底中央部までの間の肉厚を定量的に捉えることが可能であったが、大きな曲げ変形を伴ってシートが金型と接触する部位では肉厚予測精度が低下した。

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