Papers by Author: Akira Shinozaki

Abstract: The mechanical properties of polymers are strongly influenced by meso-scale (10-9~10-3 m) structure such as entanglement, molecular weight distribution, orientation, etc. It is important to understand the relationship between the mechanical properties of polymeric material and meso-scale structure. Some studies related to the relationship have been made. However detail of the relationship is still unclear. Especially, the studies emphasize on entanglement and branch are few. This study aims to clear the role of entanglement and branch for mechanical properties by simulating the meso-scale structure using 3D network models. In the models, there are two structures considered. One of them has no branch, and, others have branch. Large strain deformation of network models is evolved via improved molecular dynamics analysis.

Abstract: The mechanical properties of polymers are strongly influenced by meso-scale (10-9-10-3 m) structure such as entanglement, molecular weight distribution, orientation, etc. It is well known that sunlight induces the UV degradation of polymers. The mechanical properties of polymer are strongly influenced by UV irradiation because of chemical change of meso-scale structure. However the detail relationship between the mechanical properties and chemical change of meso-scale structure is not clear. In this study, it is aimed to clear this relationship by the simulation. Network models considered the meso-scale structure are constructed. Degradation is described to delete the chain elements in the network model. Large strain deformation of these network models is evolved via molecular dynamics analysis improved by us. It is possible to describe the degradation by this method.

Abstract: The mechanical properties of polymers are strongly influenced by meso-scale structure such as entanglement, orientation, folded chain, etc. However, the relationship between the meso-scale structure and macro-scale mechanical properties of polymers has not been clarified. In this paper, network models of polymer chains are introduced to simulate the meso-scale interactions. From the FEM analysis of this model, the effects of interactions on macro-scale mechanical properties are investigated.