热活化型水性聚氨酯胶粘剂的合成及应用

Synthesis and application of thermal activation type waterborne polyurethane adhesive

以混合型二异氰酸酯[HDI(六亚甲基二异氰酸酯)/TDI(甲苯二异氰酸酯)]、结晶性聚酯二元醇和水溶性磺酸盐扩链剂(A-50)等为基本原料,合成了一种PVC(聚氯乙烯)合成革用热活化型WPU(水性聚氨酯)胶粘剂,并着重探讨了软硬段结构、DMPA(二羟甲基丙酸)和胺类扩链剂对该胶粘剂性能的影响。研究结果表明:当n(TDI)∶n(HDI)=30∶70、n(—NCO)∶n(—OH)=1.4∶1、w(DMPA)=5%(相对于WPU质量而言)和A-50扩链度为40%时,WPU胶粘剂具有优异的剥离强度(37 N/25 mm)、较低的热活化温度(55℃),并且其胶膜表现出良好的耐水性(吸水率为11.0%)和耐热性(110℃),而且在140℃时可快速熔融变黏,冷却降温后的性能也较稳定。

With hybrid diisocyanate[HDI （hexamethylene diisocyanate）/TDI （toluene diisocyanate）], crystalline polyester diol and water soluble sulfonate chain extender （A- 50） as basic raw materials, a thermal activation type WPU （waterborne polyurethane） adhesive for PVC （polyvinyl chloride） synthetic leather was synthesized. And the influences of the soft-hard segment structure, DMPA （dihydroxy methyl propionic acid） and amine chain extender on the properties of adhesive were emphatically discussed. The research results showed that the WPU adhesive had the excellent peeling strength （ 37 N/25 mm ） , lower thermal activation temperature （ 55 ℃ ） , and its film had the good water resistance （water absorption at 11.0% ） and heat resistance （ 110 ℃ ）, and that could quickly be melted to glue at 140 ℃, and its properties after cooling were more stable when molar ratios of n（TDI） ：n （HDI） and n（-NCO） ： n（-OH） were 30：70 and 1.4：1 respectively, mass fraction of DMPA was 5% in WPU, and A-50＇ s extender chain degree was 40%.