反应型聚氨酯热熔胶主要性能影响因素研究

Research on Main Performance Influence Factors of Reactive Polyurethane Hot-melt Adhesive

采用二苯基甲烷二异氰酸酯(MDI)、不同的低聚物二醇及增黏剂等原料制备了反应型聚氨酯热熔胶。研究了低聚物二醇种类、分子量以及增黏树脂EVA用量对反应型聚氨酯热熔胶的黏度、开放时间、初粘强度和终粘强度的影响。结果表明,相对分子质量为2 000的聚己二酸丁二醇酯二醇(PBA)较适合作为合成聚氨酯热熔胶的低聚物二醇,随着低聚物二醇结晶性的增强、分子量的增加,以及增黏树脂EVA用量的提高,聚氨酯热熔胶的黏度增大、开放时间缩短、初粘强度提高。但是终粘强度则是随着增黏树脂用量的增多而先升高后降低,在增黏树脂添加量10%时最高。

Reactive polyurethane hot melt adhesive was prepared by diphenylmethane diisocyanate(MDI)oli gomer diol and tackifier,etc.The effects of the type of oligomer diol,the molecular weight of the oligomer diol and the amount of tackifying resin EVA on the viscosity,opening time,initial and final viscosity of the reactive polyure thane hot melt adhesive were studied.The results showed that the viscosity of polyurethane hot melt adhesive was increased,the opening time was shortened and initial viscosity increased when the crystallinity,the molecular weight of oligomer diol and EVA content were increased.Polyester diol PBA 2000 was a suitable oligomer diol in this case.The ultimate adhesive strength was first increased and then decreased with the increase of the amount of tackifying resin,which was the highest when the tackifying resin was 10%of the prepolymer mass.