LDPE接枝聚氨酯对TPU/LDPE共混物流变行为的影响

Impact of LDPE grafted polyurethane on rheological behavior of TPU/LDPE blends

以低密度聚乙烯(LDPE)接枝聚氨酯(LDPE-g-PU)为增容剂,利用旋转流变仪研究了热塑性聚氨酯弹性体(TPU)/LDPE/LDPE-g-PU共混物的流变行为,分别以温度和增容剂用量为变量研究了共混物的储能模量、耗能模量、损耗角正切以及复数黏度与剪切速率的关系。结果表明:TPU/LDPE/LDPE-g-PU共混物为假塑性流体;加入LDPE-g-PU后,共混物的复数黏度先降低后升高,当w(LDPE-g-PU)为1%时,共混物的复数黏度降至最低;升高温度对共混物复数黏度的影响根据角频率的不同有所差异,低频率时复数黏度升高,高频率时复数黏度降低。

Low density polyethylene（LDPE）grafted thermoplastic polyurethane（LDPE-g-PU）is used as compatibilizer to study the rheological behavior of thermoplastic polyurethane elastomer（TPU）/LDPE/LDPEg-PU blends in this paper by use of rotational rheometer. Relationship of storage modulus, loss modulus, loss tangent and complex viscosity with shear rate are studied by taking the dosage of compatibilizer and temperature as variables. Results indicate that the TPU/LDPE/LDPE-g-PU blends are pseudoplastic fluid. The complex viscosity of the blends drops and then rises after adding LDPE-g-PU, when w（LDPE-g-PU）is 1%, the complex viscosity of the blends reaches minimum. The influence of temperature on complex viscosity of blends changes with frequency, that is,complex viscosity goes up at low frequency and falls at high frequency.