热分析法评价反应性热熔胶的初粘强度

Thermal Analytical Characterization of Green Strength of Reactive Hot Melt Adhesive

用不同比例的聚己二酸己二醇酯 ( PHA) /聚己二酸一缩二乙二醇酯 ( PDEA)和 4 ,4′-二苯甲烷二异氰酸酯 ( MDI)合成了不同结晶含量的反应性热熔胶 ( Reactive hotmeltadhesive,RHMA) .结果表明 ,由 DSC得到的 RHMA的熔融热及初粘剪切强度随 PDEA的质量分数的增加而递减 ,在 m( PHA)∶ m( PDEA) =5 0∶ 5 0时 ,合成得到的 RHMA已表现不出初粘性 .利用动态热机械分析 ( DMTA)得到了 RHMA的储能模量 ( E′)和损耗角正切 ( tanδ)随温度的变化关系 ,并由此计算了与 RHMA初粘性能紧密相关的热粘指数 .结果表明 ,DSC和 DMTA的测试结果和 RHMA的初粘强度之间存在良好的相关性 .

Isocyanate-capped reactive hot melt adhesive(RHMA) based on poly(hexanediol adipate)(PHA)/poly(diethylene glycol adipate) (PDEA) and methylene di-p-phenyl diisocyanate(MDI) have been prepared. The relationship between melting enthalpy of RHMA and their green strengths has been investigated using DSC. It suggests that the green strength of RHMA decreased with increase in PDEA content in the adhesives. Storage modulus (E′) and loss tangent (tanδ) of RHMA have been determined by DMTA. It is concluded that the DSC and DMTA results have good corelationship with green strength of RHMA.