高强度木单板/异氰酸酯复合材料制备及性能优化OACSTPCD

The pretreatment of wood by removing lignin is an important method to prepare high-strength wood-based composites.However,the process of delignification would generate a large amount of waste liquid and is not condu-cive to industrial applications.In the context of the current"Dual Carbon"goal and green development,it is particu-larly important to explore a low-carbon,environmentally friendly,simple and efficient preparation method for high-strength wood-based composites to improve the high value-added utilization of wood.Based on this,birch veneer and polymerized diphenylmethane diisocyanate(pMDI)were used as raw materials in this study.The effects of the hot-pressing temperature,hot-pressing time and the amount of pMDI on the mechanical properties,water resistance and surface color of pMDI-WC were investigated by the orthogonal experiment.The orthogonal experiment results showed that the hot-pressing temperature,hot-pressing time and the addition amount of pMDI have significant effects on the mechanical properties,water resistance and surface color of pMDI-WC.The optimal hot-pressing temperature,hot-pressing time and pMDI addition amount of pMDI-WC were 170 ℃,20 min and 10％with a sample thickness of 6 mm,respectively.The pMDI-WC with excellent mechanical properties was prepared under the optimal process condi-tions,and its flexural strength and tensile strength were 473.59 and 408.56 MPa,respectively.The pMDI-WC had the best water resistance under the conditions of the hot-pressing temperature of 180 ℃,hot-pressing time of 20 min and pMDI addition of 20％.The pMDI-WC has the characteristics of light-weight and high-strength,and its preparation process is simple and green,which is of great significance to improve the utilization of wood with high added value and the green development of composite materials.