1991 Fiscal Year Final Research Report Summary
Rheo-Optical Studies on High Performance Elastomers for Medical Use.
| Project/Area Number |
01460229
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
高分子物性
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| Research Institution | Kyoto Institute of Technology |
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Principal Investigator |
NOMURA Shunji Kyoto Inst. of Tech., Dept. of Polymer Sci. & Eng., Professor, 繊維学部, 教授 (10026073)
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| Co-Investigator(Kenkyū-buntansha) |
SHIBAYAMA Mitsuhiro Kyoto Inst. of Tech., Dept. of Polymer Sci. & Eng., Associate Professor, 繊維学部, 助教授 (00175390)
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| Project Period (FY) |
1989 – 1991
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| Keywords | Elastomers for Medical Use / Dynamic Infrared Dichroism / Segmented Poly(urethane)s / FTIR / Mechanical Fatigue |
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| Research Abstract |
It was the purpose of this research to clarify change of microphase separated structure in elastomers due to mechanical fatigue and to develop high performance elastomers for medical use.
1. Static and dynamic infrared absorption dichroism measurements were performed in order to study the deformation mechanism of segmented poly (urethaneurea) s (SPUU), having different soft segment molecular weights, over a wide range of temperatures and frequency, and the following facts were disclosed :
(1) The capability of orientation for the soft segments decreases at high temperature or low frequency. This is due to increase in the effective length of the soft segments by lowering the number of effective cross-links in the soft segment matrix at high temperature or low frequency.
(2) The capability of the negative orientation of the hard segments in SPUU having high soft segment molecular weight decreases with increasing temperature but that of low molecular weight does not depend either temperature or frequency. This can be explained based on differences in cohesive force in hard segment domains.
2. The mechanical and orientation behavior of segmented polyurethan (SPU) with a polydinethylsiloxane component (PES) in the main chain was investigated, and the following facts were disclosed :
(1) Both hard and soft segments are oriented positively from the beginning of stretching, which is completely different from SPUU. This can be explained by low cohesive power of the hard segments.
(2) Systematic variations in the mechanical and thermal properties were found with the soft segment molecular weight. The higher the molecular weight, the higher the degree of completion in microphase separation.
(3) The PES component in the soft segment reduces the capability of crystallization of PTMG but raises the degree of completion in microphase separation between the soft and hard segments.
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