We discussed the effect of Polycarbonate (PC) type and Vapor-Grown Carbon Fiber (VGCF) size on the mechanical properties of PC/VGCF composites prepared by melt compounding using a twin screw extruder. Four kinds of PC which have different melt volume flow rate, and two kinds of VGCF which have different aspect ratio (VGCF-S which is the aspect ratio of 100, and VGCF-H which is the aspect ratio of 40.) were used in this study. In addition, the several VGCF contents were set up in each PC/VGCF composite. The Young′s modulus of PC/VGCF composite overall increases with VGCF content in each case. However, the enhancement of Young′s modulus in PC with low and high melt viscosity is little. Tensile strength, which is maximum stress during tensile testing, of PC/VGCF composite increases a little with VGCF content except for the case using PC with high melt viscosity. Though VGCF-S is the smaller surface area and higher aspect ratio as compared with VGCF-H, the effect of each VGCF on the mechanical properties of PC is almost same. The dispersion, aggromeration and breaking of VGCF could be interpreted from the investigation of the morphology, thermal properties and Halpin-Tsai model, which predicts the Young′s modulus of the polymer/fiber composites. We concluded that the VGCF could be easily broken in high viscosity matrix.

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In this century, issues such as “comfort”, “safety”, “user-friendliness”, and “greenness” have become key concepts, not only the production of regenerate fibers, but also the utilization of natural materials, which has been on the rise. In addition, for diversifying and improving the properties of textile products, it is necessary to develop new techniques and methods for making textile materials. Our newly-developed glucomannan fiber produced from industrial waste meets all of those requirements and has the potential to exceed them. To make effective use of industrial waste and reduce the amount produced, as well as to improve our daily lives, we investigated the development of novel hemicellulose fiber made from powdered konjac by-products, “Tobiko” in Japanese.
The results are as follows: (1) using konjac by-products of industrial waste, environment-friendly textile products can be developed, (2) a novel hemicelluloses fiber can be made from konjac glucomannan by means of the cuprammonium process, (3) finally, we believe this to be a new unique application for konjac fiber.

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In this study, we tried to simulate human bodily movements to put on clothing, and succeeded to simulate the movement. This is a combination of mechanical clothing simulation and measurement of bodily movement.
In the clothing simulation, cloth is assumed to be continuous elastic body and mechanically formulated. The equilibrium state of cloth is calculated by minimization of accumulated energy based on the strains and forces determined by deformation of cloth. Though to put on clothing is dynamic movements, the static calculation was iterated in the simulation because the movements here were very slow.
A vest was targeted because of its simple structure. A clothing model of a vest was constructed from paper patterns of component parts. The bodily movements to put on clothing were measured by a motion capture system. A virtual human model was moved according to the measured data of the movements.
First, shape of a vest in stable state hanging in the air was calculated, human body model was started to move, then the shape of the vest in stable state was calculated in every step of the movements. By the above calculation, the movements to put on clothing were reproduced with the simulation.

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