Activity of counterions in hydrogels based on poly(acrylic acid) and poly(methacrylic acid): Potentiometric measurements / Safronov A. P.,Kamalov I. A.,Shklyar T. F.,Dinislamova O. A.,Blyakhman F. A. // POLYMER SCIENCE SERIES A. - 2012. - V. 54, l. 11. - P. 909-919.

ISSN/EISSN:

0965-545X / нет данных

Type:

Article

Abstract:

The behavior of partially ionized weakly crosslinked gels based on poly(acrylic acid) and poly(methacrylic acid) undergoing contraction in the presence of a low-molecular-mass salt is studied experimentally. The concentration dependences of the enthalpies of swelling of gels in water and aqueous solutions with potassium chloride concentrations of 1, 10, and 100 mmol/L are determined via the method of isothermal calorimetry. On the basis of the obtained data, the enthalpy parameter of interaction between a polymer network and a medium is estimated as a function of the amount of the salt. This parameter does not exceed 0.3 and monotonically decreases with an increase in the concentration of the salt. The Donnan potential of gels depending on the concentration of KCl in the external solution is measured via the method of potentiometry with the use of capillary electrodes, and the activity of potassium counterions in the medium of hydrogel is calculated. The main factor that causes contraction of polyelectrolyte gels in a solution of a low-molecular-mass salt is a decline in the activity of counterions that leads to a decrease in the osmotic pressure inside the gel. A decline in activity may be associated with both a reduction in the activity coefficient and ionic association processes in the hydrogel.

Author keywords:

POLYELECTROLYTE SOLUTIONS; ACTIVITY-COEFFICIENTS; DONNAN EQUILIBRIA; GELS; COLLAPSE; POLYMETHACRYLATE; PARAMETER; ENTHALPY; SALT

DOI:

10.1134/S0965545X12090088

Web of Science ID:

ISI:000311202300011

Соавторы в МНС:

Другие поля

Поле	Значение
Month	NOV
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
Keywords-Plus	POLYELECTROLYTE SOLUTIONS; ACTIVITY-COEFFICIENTS; DONNAN EQUILIBRIA; GELS; COLLAPSE; POLYMETHACRYLATE; PARAMETER; ENTHALPY; SALT
Research-Areas	Polymer Science
Web-of-Science-Categories	Polymer Science
Author-Email	alexander.safronov@usu.ru
ResearcherID-Numbers	Blyakhman, Felix/B-7807-2011
ORCID-Numbers	Blyakhman, Felix/0000-0003-4434-2873
Number-of-Cited-References	28
Usage-Count-Last-180-days	2
Usage-Count-Since-2013	30
Journal-ISO	Polym. Sci. Ser. A
Doc-Delivery-Number	038VN