聚合物压敏胶的动态粘弹频率谱表征

Dynamic Viscoelastic Frequency Spectrum Characterization of Pressure-Sensitive Adhesive

针对丙烯酸乳液型和橡胶热融型压敏胶在宏观三大力学性能上的差异,运用动态粘弹频率谱表征技术,在压敏胶的粘合频率(0.01 Hz)至剥离频率(100 Hz)范围内,对两种不同类型压敏胶的流变学行为进行了对比研究.研究结果表明:在实验频率范围内,两类压敏胶在储能模量(E′)、损耗模量(E″)、损耗因子(tanδ)和粘度(η)等性质上有较大差别并呈现出不同的变化规律.根据实验结果和聚合物流变学基本理论,粘合频率下(0.01 Hz左右),E′较低的聚合物其压敏胶初粘性较高;剥离频率下(100 Hz左右),E″较大的聚合物其压敏胶的180°剥离强度较大;η,E′较高的聚合物其压敏胶持粘时间较长.

For the difference in mechanical property between acrylic emulsion and hot melt pressuresensitive adhesive（PSA）, the rheology behaviors of the two PSAs were studied. They were characterized by dynamic-viscoelastic frequency-scanning technique in the range of adhesion frequency （0.01 Hz） to peeling frequency （100 Hz）. The results indicated that storage modulus （E＇）, loss modulus （E＂）, loss factor （tanδ） and viscosity （η） have a great difference between acrylic emulsion and hot melt PSA, and these characteristics showed different transformation rules. Conclusions can be drawn considering the experimental results based on polymer rheology theory that low polymer storage modulus leads to great initial adhesion under the adhesion frequency （0.01 Hz）, and polymers with high value of storage modulus have great sustained adhesion, and those with great values of η,E＇ give long sustained adhesion time under the peeling frequency（100 Hz）.