Advances in Engineering Advances in Engineering features breaking research judged by Advances in Engineering advisory team to be of key importance in the Engineering field. Papers are selected from over 10,000 published each week from most peer reviewed journals.
Colloid and Polymer Science, 2013, Volume 291, Issue 8, pp 1829-1842.
V. V. A. Fernández, J. Aguilar, F. Becerra, J. C. Sánchez-Díaz, J. F. A. Soltero, P. Ortega-Gudiño,E. Hernandez, F. Bautista, J. E. Puig.
Departamento de Ciencias Tecnológicas, Universidad de Guadalajara, Av. Universidad #1115, Ocotlán, Jalisco, 47820, Mexico and
Departamento de Química, Universidad de Guadalajara, Boul. M. García Barragán #1451, Guadalajara, Jalisco, 44430, Mexico and
Departamento de Ingeniería Química, Universidad de Guadalajara, Boul. M. García Barragán #1451, Guadalajara, Jalisco, 44430, Mexico and
Departamento de Física, Universidad de Guadalajara, Boul. M. García Barragán #1451, Guadalajara, Jalisco, 44430, Mexico.
Abstract
The thermoresponsive behavior and mechanical properties of nanostructured hydrogels, which consist of poly(acrylamide) nanoparticles embedded in a cross-linked poly(N-isopropylacrylamide) hydrogel matrix, are reported here. Nanostructured hydrogels exhibit a tuned volume phase transition temperature (T VPT), which varies with nanoparticle content in the range from 32 up to 39–40 °C. Moreover, larger equilibrium water uptake, faster swelling and de-swelling rates, and larger equilibrium swelling at 25 °C were obtained with nanostructured hydrogels compared with those of conventional ones. Elastic and Young’s moduli were larger than those of conventional hydrogels at similar swelling ratios. The tuned T VPT and the de-swelling rate were predicted with a modified Flory–Rehner equation coupled with a mixing rule that considers the contribution of both polymers. These behaviors are explained by a combination of hydrophilic/hydrophobic interactions and by the controlled inhomogeneities (nanoparticles) introduced by the method of synthesis.
