SWELLING OF COVALENTLY CROSS-LINKED ALGINATE GELS - INFLUENCE OF IONIC SOLUTES AND NONPOLAR-SOLVENTS

被引:102
作者
MOE, ST [1 ]
SKJAKBRAEK, G [1 ]
ELGSAETER, A [1 ]
SMIDSROD, O [1 ]
机构
[1] UNIV TRONDHEIM,NORWEGIAN INST TECHNOL,DEPT PHYS,N-7034 TRONDHEIM,NORWAY
关键词
D O I
10.1021/ma00066a017
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
The equilibrium swelling volume of covalently crosslinked sodium alginate (a highly ionized stiff polymer network) gels has been studied as a function of electrolyte concentration, pH, and concentration of salts in ethanol-water mixtures. It is shown by numerical analysis of the Flory theory for swelling of gels that the ionic contribution to swelling seems to be the main determining factor for the swelling of these gels. Volume changes in aqueous solutions may be explained mainly by the ionic contribution to swelling. Reduced swelling and marked hysteresis are observed when the gels are exposed to low pH or cations that induce gelling in soluble Na-alginate. In contrast to predictions found in the literature, no discrete volume changes have been observed as a result of altering solvent composition. This discrepancy is attributed to the effect of the Donnan equilibrium and the high stiffness of the alginate chains. The gel volume changes in ethanol-water mixtures resemble the solubility of uncrosslinked alginates.
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页码:3589 / 3597
页数:9
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共 49 条
[11]  
HAMERSTRAND GE, 1960, CEREAL CHEM, V37, P519
[12]  
HAUG A, 1964, THESIS U TRONDHEIM
[13]   VOLUME PHASE-TRANSITION IN A NONIONIC GEL [J].
HIROKAWA, Y ;
TANAKA, T .
JOURNAL OF CHEMICAL PHYSICS, 1984, 81 (12) :6379-6380
[14]   VOLUME-PHASE TRANSITIONS OF IONIZED N-ISOPROPYLACRYLAMIDE GELS [J].
HIROTSU, S ;
HIROKAWA, Y ;
TANAKA, T .
JOURNAL OF CHEMICAL PHYSICS, 1987, 87 (02) :1392-1395
[15]  
HOLMBERG L, 1983, THESIS SWEDISH U AGR
[16]   EFFECT OF ELECTROSTATIC INTERACTIONS ON PHASE-TRANSITION IN THE SWOLLEN POLYMERIC NETWORK [J].
ILAVSKY, M .
POLYMER, 1981, 22 (12) :1687-1691
[17]   VOLUME TRANSITION IN A GEL DRIVEN BY HYDROGEN-BONDING [J].
ILMAIN, F ;
TANAKA, T ;
KOKUFUTA, E .
NATURE, 1991, 349 (6308) :400-401
[18]   REACTION OF EPICHLORHYDRIN WITH CARBOHYDRATE POLYMERS .2. STARCH REACTION-MECHANISM AND PHYSICOCHEMICAL PROPERTIES OF MODIFIED STARCH [J].
KARTHA, KPR ;
SRIVASTAVA, HC .
STARKE, 1985, 37 (09) :297-306
[19]   REACTION OF EPICHLOROTHYDRIN WITH CARBOHYDRATE POLYMERS .1. STARCH REACTION-KINETICS [J].
KARTHA, KPR ;
SRIVASTAVA, HC .
STARKE, 1985, 37 (08) :270-276
[20]   STUDY OF CROSSLINKING REACTION BETWEEN EPICHLOROHYDRIN AND STARCH [J].
KUNIAK, L ;
MARCHESSAULT, RH .
STARKE, 1972, 24 (04) :110-+