Efficient Utilization of Ozonized Lignin

将工业木质素或其臭氧氧化产物的碱性溶液与水溶性环氧化合物、聚乙二醇二缩水甘油醚(PRGDGE)和固化剂混合，研制出一种新的树脂体系。通过改变木质素/环氧树脂的共混比或化学结构合成了木质素/环氧树脂。研究了固化树脂膜的粘弹性能，随着树脂中硫酸盐木质素含量的增加，固化树脂玻璃化转变的吸收峰随着铺展向更高温度移动。结果表明，改变PEGDGE种类和固化剂可以改善树脂固化过程中的草型转变。乳液型双酚A二缩水甘油醚(DGEBA)的加入也能提高固化树脂的玻璃化转变温度。由于GRASS转变只有一个较宽的分散峰，这表明固化树脂具有相容性，可以形成一种互穿聚合物网络(IPNS)。由于这些树脂在较低温度下具有较大的二次弛豫峰，因此它们有可能应用于减震材料和胶粘剂。臭氧处理对固化树脂的力学性能影响不明显。

A new resin system was developed only by mixing the alkaline solution of industrial lignin or its ozonized products with water soluble epoxy compound, polyethylene glycol diglycidyl ether (PRGDGE), and curing reagent. The lignin/epoxy resins were synthesized by alternation the blend ratio or their chemical structure. The viscoelastic properties of cured resin films were investigated.As the content of the kraft lignin in the resins increased, the absorption peak due to the glass transition for cured resins shifted to a higher temperature with spreading. It was found that the grass transition of cured resins can be modified by changing kinds of PEGDGE and curing reagents. Addition of the emulsion type of diglycidyl ether of bisphenol A (DGEBA) to the blendings also could make the grass transition temperature of cured resins higher. Since only one broad dispersion peak due to the grass transition could be observed, it was suggested that the cured resins had compatibility to form a kind of IPNs (Interpenetrating Polymer Networks).The possibility of application of these resins to damping materials and adhesives was strongly suggested, since they had a large secondary relaxation peak at lower temperature. The effect of ozone-treatment on mechanical properties of cured resins was not obvious.