Journal of Pharmaceutical Investigation
- Volume 29 Issue 3
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- Pages.193-203
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- 1999
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- 2093-5552(pISSN)
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- 2093-6214(eISSN)
Steady Shear Flow Properties of Aqueous Poly(Ethylene Oxide) Solutions
폴리에틸렌옥사이드 수용액의 정상유동 특성
-
Song, Ki-Won
(College of Engineering, Pusan National University) ;
- Kim, Tae-Hoon (College of Engineering, Pusan National University) ;
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Chang, Gap-Shik
(College of Engineering, Pusan National University) ;
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An, Seung-Kook
(College of Engineering, Pusan National University) ;
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Lee, Jang-Oo
(College of Engineering, Pusan National University) ;
-
Lee, Chi-Ho
(College of Pharmacy, Pusan National University)
-
송기원
(부산대학교 공과대학) ;
- 김태훈 (부산대학교 공과대학) ;
-
장갑식
(부산대학교 공과대학) ;
-
안승국
(부산대학교 공과대학) ;
-
이장우
(부산대학교 공과대학) ;
-
이치호
(부산대학교 약학대학)
- Published : 1999.09.20
Abstract
In order to investigate systematically the steady shear flow properties of aqueous po1y(ethylene oxide) (PEO) solutions having various molecular weights and concentrations, the steady flow viscosity has been measured with a Rheometrics Fluids Spectrometer (RFS II) over a wide range of shear rates. The effects of shear rate, concentration, and molecular weight on the steady shear flow properties were reported in detail from the experimentally measured data, and then the results were interpreted using the concept of a material characteristic time. In addition, some flow models describing the non-Newtonian behavior (shear-thinning characteristics) of polymeric liquids were employed to make a quantitative evaluation of the steady flow behavior, and the applicability of these models was examined by calculating the various material parameters. Main results obtained from this study can be summarized as follows: (1) At low shear rates, aqueous PEO solutions show a Newtonian viscous behavior which is independent of shear rate. At shear rate region higher than a critical shear rate, however, they exhibit a shear-thinning behavior, demonstrating a decrease in steady flow viscosity with increasing shear rate. (2) As an increase in concentration and/or molecular weight, the zero-shear viscosity is increased while the Newtonian viscous region becomes narrower. Moreover, the critical shear rate at which the transition from the Newtonian to shear-thinning behavior occurs is decreased, and the shear-thinning nature becomes more remarkable. (3) Aqueous PEO solutions show a Newtonian viscous behavior at shear rate range lower than the inverse value of a characteristic time
Keywords
- Aqueous PEO solutions;
- Steady shear flow properties;
- Non-Newtonian behavior(Shear-thinning characteristics);
- Characteristic time;
- Critical shear rate;
- Flow models