Abstract: The rice straw was liquefied by using polyethylene glycol 400 and glycerol as mixed liquefier and concentrated sulfuric acid as catalyst.And this liquefied rice straw was employed to prepare the polyurethane (PU) foam, and followed by a characterization of its structure and performance.The effects of isocyanate index, water content, the proportion of the catalyst, and the amount of silicone oil on properties of the PU foam were studied.The results showed that the PU foam can be prepared with good properties by using the liquefied rice straw and isocyanate (PAPI) as raw materials, under the optimum condition, namely, 2% weight content of water against the mass of the liquefied rice straw, triethylenediamine and stannous octoate composite catalysts with the weight ratio of 0.1:0.3(g :g), 4% silicone oil as foam stabilizer against liquid agent and the isocyanate index of 1.2.And the properties of these PU foam i.e. the density, the tensile strength and the compressive strength were 35.78 kg/m³, 222.60 kPa, 110.90 kPa, respectively.TGA analysis indicated that rice straw-based PU foam had good heat resistance with the initial decomposition temperature of 241 ℃ and the most rapid decomposing temperature of 420 ℃.

Key words: rice straw, liquefaction products, polyurethane foam