木质素-糠醇-乙二醛树脂基砂轮片的制备与测试

Preparation and Testing of Lignin-Furfuryl Alcohol-Glyoxal Resin Based Grinding Wheel

将木质素、糠醇与乙二醛在酸性条件下反应,制备新型无甲醛木质素基砂轮片来替代传统酚醛树脂基砂轮片。对木质素-糠醇树脂的基本理化性能测试和砂轮片抗压强度、弯曲强度和硬度检测对树脂的粘度、固含量、凝胶时间及砂轮片的力学性能进行表征,采用电动角磨机对砂轮片的切割性能进行测试,应用扫描电子显微镜(SEM)对木质素-糠醇树脂基砂轮片的微观构造观测。结果表明:在乙二醛的交联作用下,木质素与糠醇在酸性条件下发生了缩聚反应;树脂的凝胶时间随着pH的增加而增加;在pH为3条件下制备的砂轮片表面孔隙较少,并且与实验室制备酚醛树脂基砂轮片相比,前者具有较高的硬度及切割强度。

A new grinding wheel based on lignin-based resin cross-linked by furfuryl alcohol and glyoxal has been prepared without formaldehyde for the replacement of the phenolic resin based grinding wheel. The viscosity, the solid content, the gel-time of resins, the compression strength, bending strength and hardness of grinding wheels were studied by the measurements of basic property of resin and mechanical property of grinding wheels. The cutting property of lignin-based grinding wheels was studied using a angle grinder machine. The microscopic structure observation of grinding wheels was carried out by the scanning electron microscopy （ SEM）. These results indicate that the condensation polymerization of lignin,furfuryl alcohol and glyoxal as a agent had been established under acid condition. With the increase of pH value,the gel-time of resin increased. The grinding wheel prepared at pH of 11 presents fewer pores. Moreover,the lignin based grinding wheel shows a higher hardness and an excellent cutting strength compared with phenolic based grinding wheel prepared in laboratory.