ISSN:
1435-1536
Keywords:
Polyvinylpyrrolidone
;
complexation
;
chain length effects
;
coil dimensions
;
intrinsic viscosity
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Changes in polyvinylpyrrolidone (PVP) coil dimensions by complexation with small organic anions were studied by dilure solution viscometry Intrinsic viscosity provides a convenient measure of the dimensions assumed by a flexible polymer chain in solution as a result of interactions with all components in its environment. Molecular interactions between PVP and sodium benzoate and salicylate were investigated over a range of low concentrations of each anion, from 2.5 to 90 mM, and as a function of five molecular weight grades of PVP. This study showed that both contraction and expansion of polymer coils were sensitive to the concentration and chemical structure of the cosolute. In addition, at high anion concentrations changes in polymer conformation by complexation were dependent on both the chain length of PVP and charge density of bound anions through excluded volume effects. Experimental results demonstrating these observations are presented in a three-dimensional surface plot of intrinsic viscosity ratio, polymer size, and anion concentration. A distinct local minimum in the surface plane was exhibited for each cosolute.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00657400
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