| 학회 |
한국고분자학회 |
| 학술대회 |
2004년 봄 (04/09 ~ 04/10, 고려대학교) |
| 권호 |
29권 1호, p.122 |
| 발표분야 |
고분자 구조 및 물성 |
| 제목 |
The Cooling Rate Effect on Sol-Gel Transition Behavior of Poly(vinyl alcohol)/DMSO/Water Mixture |
| 초록 |
The physical gelation behavior of poly(vinyl alcohol)(PVA) in aqueous dimethyl sulfoxide was investigated. Analysis of multifrequency oscillatory shear experiment determined the apparent gel temperature that tanδ becomes independent of the frequency of the applied oscillation. The mean change rate of storage and loss modulus at the determined gel temperature, namely mean relaxation exponent(nm), was calculated by linear fitting. The values were varied from 0.42 to 0.89. Shear flow experiment indicated the selectivity of dependence of cooling rate on nm was due to the regime of solution concentration in solution state. In a dilute solution regime gelation behavior did not observed. In an unentangled semi-dilute regime gelation behavior observed but the dependence of cooling rate on nm did not appear. However, in an entangled semi-dilute regime the slower cooling rate increased nm, which can be explained by the relation of competition between phase separation and gelation and cleared by frequency sweep test of the PVA gels. |
| 저자 |
김종원, 김호겸, 최진환, 박종환, 박종건, 민경은
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| 소속 |
경북대 |
| 키워드 |
poly(vinyl alcohol); relaxation exponent
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| E-Mail |
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