1. Department of Applied Chemistry, Graduate School of Engineering, Osaka University, , Suita, Osaka, 565–0871 Japan;2. The Center for Advanced Medical Engineering and Informatics, Osaka University, , Suita, Osaka, 565–0871 Japan
Abstract:
Improving fragility is important for the practical application of gels. In this study, the mechanical strength of gels composed of poly(N‐vinyl acetamide) (PNVA) and glycols is investigated focusing on the retained solvent in the gels. The solvent for the PNVA hydrogel is adequately replaced by various glycols. Using poly(ethylene glycol) (PEG) with molecular weights of 400 or 600 g mol?1, the compressive strength of the gel is dramatically enhanced to approximately 10 MPa while that of hydrogel is 0.2 MPa. This is because of solvent viscosity, interaction between PEG and PNVA, and the favorable aggregation of the PNVA. From FTIR spectroscopy investigations, the absorption bands of the carbonyl and amino groups of PNVA gels with PEG400 are shifted as compared with PNVA gels in water, suggesting hydrogen bond formation.
