Template Action, Morphology and Property of Baicalin on Thermo-Responsive Hydrogel

A kind of novel poly(N-isopropylacrylamide) hydrogel based baicalin was prepared in dimethyformamide by using flavonoids baicalin as functional monomer. The structure, morphology, temperature-sensitivity and mechanical property were studied by Fourier transform infrared spectroscopy(FT-IR), ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy(SEM) and thermal analysis. Results show that with the addition of baicalin, the prepared hydrogel turned into yellow from transparency, and the wrinkle occurs in pore wall of the prepared hydrogel. The pore size increases with the increasing of the baicalin content. The baicalin mainly plays the template effect in the matrix of hydrogel. The volume phase transition temperature (VPTT) keeps still at 32—34 °C, but the temperature-sensitivity increases. The swelling ratios and oscillating swelling-deswelling properties are improved by the introduction of baicalin, and yet the storage modulus.