温湿度和紫外老化对纸浆模塑材料性能的影响

目的 研究温度、湿度和紫外老化对脱木素和未脱木素纸浆模塑材料性能的影响，定量地对比不同因素作用下2种材料的力学性能差异。方法 以废纸浆为原料，经打浆、脱木素、湿成型、热压等工艺制得脱木素和未脱木素等2种纸浆模塑材料；模拟不同的温湿度和紫外老化环境，测试2种纸浆模塑材料物理力学性能的变化。结果 在同等条件下，脱木素材料的拉伸强度与弯曲强度均高于未脱木素材料；2种材料的拉伸强度、弹性模量和弯曲强度随着含水率升高而大幅降低；当温度为20 ℃、含水率为0~40%时，脱木素材料的拉伸强度下降了45 MPa，未脱木素材料的拉伸强度下降了35 MPa。当温度为0 ℃、含水率为0~40%时，脱木素材料的弯曲强度下降了70 MPa，未脱木素材料的弯曲强度降低了62 MPa；当含水率低于20%时，脱木素材料的拉伸性能和弯曲性能更易受到温度影响；虽然2种材料的拉伸性能和弯曲性能均随着紫外老化时间的延长而不断降低，但其影响程度远小于温湿度。结论 湿度对材料的力学性能影响最大，其次是温度和紫外老化；脱去木素有利于提高纸浆模塑材料的力学性能和抗紫外老化性能。

Effects of Temperature, Humidity and Ultraviolet Aging on Properties of Pulp Molding Materials

The paper aims to study effects of temperature, humidity and UV aging on properties of delignified and unde-lignin pulp molding materials, to quantitatively compare the differences in mechanical properties of the two materials under different factors. With waste paper pulp as raw material, pulping, delignification, wet forming, hot pressing and other processes were carried out to obtain two kinds of pulp molding materials: delignification and non-de-lignin; different temperature and humidity and ultraviolet aging environments were simulated to test changes in the physical and mechanical properties of two pulp molding materials. Under the same conditions, the tensile strength and flexural strength of delignified materials were higher than that of unde-lignin materials; the tensile strength, elastic modulus and flexural strength of the two materials decreased greatly with the increase of water content; at 20 °C and water content of 0~40%, the tensile strength of the delignified material was reduced by 45 MPa, and the tensile strength of the unde-lignin material was decreased by 35 MPa. At 0 °C and water content of 0~40%, the bending strength of the delignified material was reduced by 70 MPa, and the bending strength of the unde-lignin material was reduced by 62 MPa; when the water content was less than 20%, the tensile properties and bending properties of lignin materials were more susceptible to temperature; although the tensile properties and bending properties of the two materials were continuously reduced with the extension of UV aging time, the degree of influence was much less than the temperature and humidity. Humidity has the greatest influence on the mechanical properties of the material, followed by temperature and UV aging. Removal of lignin is beneficial to improve the mechanical properties and UV aging resistance of the pulp molding materials.