Swelling and Contraction of Ferrogels Based on Polyacrylamide in a Magnetic Field / Safronov A. P.,Terziyan T. V.,Istomina A. S.,Beketov I. V. // POLYMER SCIENCE SERIES A. - 2012. - V. 54, l. 1. - P. 26-33.

ISSN/EISSN:

0965-545X / 1555-6107

Type:

Article

Abstract:

The equilibrium swelling of magnetoactive ferrogels based on the copolymer of acrylamide with 10\% potassium acrylate in water is studied. The gels are filled with strontium ferrite and/or magnetite taken in amounts of 20, 40, 60, and 80 parts per 100 parts of the polymer by weight. In the absence of a magnetic field, as the content of the filler is increased, the degree of swelling tends to increase for the gels containing strontium ferrite and to decrease for the magnetite-containing gels. In the structure of hydrogels, strontium ferrite particles possessing a permanent magnetic moment form a microscopic network from chain aggregates, while the particles of magnetite, a magnetically soft material, give rise to disordered aggregates. The enthalpy of hydration of ferrogel polymeric matrices weakly depends on the nature and amount of the introduced filler: The interaction parameter takes small positive values in the range 0.10-0.18. In a homogeneous magnetic field of 365 mT, the degree of swelling decreases at a small filler content for both types of ferrogels. This effect is accompanied by elongation of a ferrogel sample along the field direction and contraction in the transverse direction. With an increase in the filler content, the inversion of both effects occurs. The applicability of concepts about the homogeneously magnetizable continuous medium to the process of magneto-striction of ferrogels is analyzed.

Author keywords:

PARAMETER; ENTHALPY; GELS

DOI:

10.1134/S0965545X12010063

Web of Science ID:

ISI:000300282200004

Соавторы в МНС:

Другие поля

Поле	Значение
Month	JAN
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
EISSN	1555-6107
Keywords-Plus	PARAMETER; ENTHALPY; GELS
Research-Areas	Polymer Science
Web-of-Science-Categories	Polymer Science
Author-Email	Alexander.Safronov@usu.ru Tatiana.terzian@usu.ru
ResearcherID-Numbers	Beketov, Igor/I-3538-2014
Funding-Acknowledgement	Russian Foundation for Basic Research {[}10-02-96015]; Scientific Potential of the Higher School; federal target program Scientific and Educational Specialists of Innovation Russia
Funding-Text	This work was supported by the Russian Foundation for Basic Research (project no. 10-02-96015), the analytical federal target program Development of the Scientific Potential of the Higher School, and the federal target program Scientific and Educational Specialists of Innovation Russia.
Number-of-Cited-References	21
Usage-Count-Since-2013	31
Journal-ISO	Polym. Sci. Ser. A
Doc-Delivery-Number	892JJ