Physical nanocomposite hydrogels filled with low concentrations of TiO2 nanoparticles: Swelling, networks parameters and cell retention studies

Publication date: 1 November 2018Source: Materials Science and Engineering: C, Volume 92Author(s): Leandro Toledo, Lisa Racine, Viviana Pérez, Juan P. Henríquez, Rachel Auzely-Velty, Bruno F. UrbanoAbstractPhysical nanocomposite hydrogels composed of poly(2-hydroxyethylmethacrylate) and titanium oxide nanoparticles at low concentrations (<1.0 wt%) were synthesized. The effect of the nanoparticle content on the water swelling and mechanical properties of the hydrogels was investigated. Additionally, to study the influence of the polymer-nanoparticle interactions, a second type of nanocomposite was synthesized using surface functionalized nanoparticles with 3-methacryloxypropyltrimethoxysilane as the filler. The pristine nanoparticles increased the swelling capacity, especially at short time scales, and greater solvent diffusion coefficients and initial swelling rates were achieved. In contrast, the nanocomposite filled with functionalized nanoparticles exhibited a diminished swelling capacity, a constant diffusion coefficient and a significant decrease in the initial swelling rate. The mechanical properties were studied by dynamic mechanical analyses using stress-relaxation tests. Two Maxwell models in parallel agreed well with the curves of the relaxation modulus as a function of time and indicated that at short relaxation times, the nanoparticles did not cause an effect, but that at longer times, the nanoparticles decreased the relaxation time. Finally, hydrogel netw...
Source: Materials Science and Engineering: C - Category: Materials Science Source Type: research