Abstract:

Corn stalk enzymatic lignin-based polyurethane foams were prepared by two methods: blending and liquefaction modification. The structure of lignin-based polyurethane foam was characterized by Fourier infrared spectroscopy(FTIR).The effect of the two types of preparation methods on physical characteristics and dynamic mechanical property of lignin-based polyurethane foams were determined by compression test and dynamic mechanical analysis(DMA), respectively. The result showed that the density of polyurethane foams from liquefaction modification method was lower than those from blending method. The gel content and compressive strength of polyurethane foams based on liquefaction product were higher than those from blending method. The maximal compressive strength of polyurethane foam reached 291 kPa when the substitution of liquefaction products up to 30% based on the total polyol. When the substitution for polyol was lower than 30%, the glass transition temperature of the polyurethane foams from liquefaction method was higher than those from blending method.

Key words: lignin, liquefaction, polyurethane foam, blending