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研究了苯乙烯-[乙烯-(乙烯-丙烯)]-苯乙烯嵌段共聚物(SEEPS)熔体的黏弹行为,求解了一些特征黏弹参数.并用改进的BSW模型模拟了松弛时间谱,给出了弹性体SEEPS最长的松弛时间(τmax).用时温叠加原理得到的储能模量(G′)-频率(ω)曲线在低ω区域出现了明显的“第二平台”.我们认为,平台的出现是由于SEEPS长链分子缠结所致.其中,PS硬段为缠结点,对大分子链的运动产生拓扑限制作用.同时研究结果还表明,可用WLF方程和Arrhenius方程很好地模拟移动因子(αT)随温度的变化,黏流活化能(Ea)为127.88kJ/mol.计算得到的平台模量(GN0)为5.646×104Pa,缠结分子量(Me)为49634.
The viscoelastic behavior of the melt of styrene - [ethylene - (ethylene - propylene)] - styrene block copolymer (SEEPS) was studied and some characteristic viscoelastic parameters were solved. The relaxation time spectrum was simulated with a modified BSW model. The longest relaxation time (τmax) of elastomer SEEPS is given.The storage modulus (G ’) -frequency (ω) curve obtained by the time-temperature superposition principle shows a distinct “second platform” in the low ω region. It is considered that the platform is caused by the entanglement of SEEPS long-chain molecules, in which the hard segment of PS is the entangled point, which has a topological restriction effect on the movement of macromolecular chains.At the same time, the results also show that WLF equation and Arrhenius equation The activation energy of viscous flow (Ea) is 127.88kJ / mol, the calculated platform modulus (GN0) is 5.646 × 104Pa, and the entanglement molecular weight (Me) is 49634.Finally,