An environmentally friendly liquefaction of wood powder was prepared by atmospheric pressure liquefaction technology to replace the non-renewable petroleum polyols in the preparation of polyurethane foam composites. The liquefaction time varied from 0 min to 140 min. The composition of liquefied products and the effects of liquefaction time on the morphology, apparent density and mechanical properties of polyurethane foam composites were investigated. The results showed that the optimal process time for the preparation of wood powder liquefaction products, which could replace traditional petroleum polyols, was 110 min. At this time, polyether polyols are the main liquefaction products, with an average molecular weight in Mn reaching 237 and average molecular weight in Mw reaching 246. The functional group of the liquefied product consisted mainly of hydroxyl, with the highest content of 1042 mg KOH/g and the lowest acid number of 1.6 mg KOH/g. In addition, the surface of the polyurethane foam based on poplar wood is dominated by closed cell foam; thus its foam has good heat insulation and heat preservation properties. At 110 min liquefaction time, the apparent density of polyurethane foam is 0.164 g/cm3 and the compression strength is 850 kPa, which is higher than that of traditional polyurethane foam (768 kPa), which is without wood powder modification. Replacing petroleum polyol with renewable wood powder liquefaction products to prepare biomass-based polyurethane foam composite materials, researching complex chemical changes in different liquefaction stages, and finding the best liquefaction conditions are of great significance to optimize the performance of polyurethane, address the shortage of resources and reduce environmental pollution.

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A large amount of plant waste from the sides of highways is trimmed and burned, which causes environmental pollution. In addition, headlight glare that occurs when two cars pass each other is dangerous. Traditional anti-glare boards are mostly made of metal, plastic, and other materials that easily age and are expensive to recycle. To recycle the plant waste and prevent glare-related accidents, in the present study, a painted wooden anti-glare board (WAB) was developed and its performance was investigated. In the WAB, there are 7 layers of eucalyptus veneers interlaced, and the mechanical strength of the board prepared with a gradient hot-pressing process after impregnation with phenolic resin was good (79.8 MPa). The wind load resistance of the WAB reached 864 N, which meets GB/T 24718 (2009) and is close to that of glass fiber-reinforced plastic anti-glare boards (914 N). After 10 cycles of weather resistance tests comprising submersion, freezing, and hot-drying, the average static bending strength of the WAB was 29.6 N/mm2. The limited oxygen index of the WAB was 26.1%. Therefore, the WAB showed good properties. The implemented research strategy broadens the application range of the wood composite material and endows it with high added value.