Improved mechanical strength and pH sensitivity via incorporation of microemulsion in hydrogel

What is it about?

Polystyrene (PS) microemulsion which polymerization was progressed up to 50%, was used as the solvent in the free-radical crosslinking polymerization of acrylic acid. Equilibrium swelling ratio and mechanical properties of PS filled-acrylic acid hydrogels were investigated and compared with unfilled hydrogels at several pH levels.

Featured Image

Why is it important?

In this PS filled hydrogel (about 35%(v) PS filled), mechanical property in the beginning of swelling was dependent on the filler concentration (presented in other paper-'Inhomogeneous swelling and mechanical properties...'), but, when the swelling ratio reached to the equilibrium, it was more dependent on the crosslinking degree. Generallly, the efficiency of filler incorporation was higher as the crosslinking degree was lower. pH sensitivity of these filled hydrogel was not so different in the unfilled system, but much more sensitive at high pH level, the swelling ratio of filled hydrogel was higher. Mechanical property of filled hydrogel when it was swollen to equilibrium, was order of magnitude stronger than in unfilled hydrogel.