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The dynamic viscoelastic response of the two-phase polymer blend systems shows the characteristics of the thermorheologically complex materials. In this paper theoretical equations for describing the dynamic viscoelastic response of such polymer blend systems have been established by means of the mechanical modeling technique. The dynamic viscoelastic response of the blend systems at any blend composition can be predicted theoretically by using the equations established, provided that the dynamic viscoelastic response of the two pure components and the mechanical model parameters are known in advance. Thus, we provide an effective method for studying the dynamic mechanical properties and the molecular relaxation characteristics of the two-phase polymer blend systems. 相似文献
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提出用两个热流变简单粘弹体的并联体系作为两相聚合物的粘弹模型,将先前的动态力学温度谱分析方法推广到两相聚合物中去.运用这种新方法从动态力学数据求出了PET/70PHB共聚物的双活化能,其中150℃左右的转变活化能为71.9kcal/mol,70℃左右的转变活化能为117.5koal/mol,这一数值与文献上PET/60PHB这个转变的活化能120kcal/mol相接近.文中还计算了共聚物在不同温度下的10s应力松弛模量,所得结果与实测值相吻合. 相似文献
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提出用两个热流变简单粘弹体的并联体系作为两相聚合物的粘弹模型,将先前的动态力学温度谱分析方法推广到两相聚合物中去.运用这种新方法从动态力学数据求出了PET/70PHB共聚物的双活化能,其中150℃左右的转变活化能为71.9kcal/mol,70℃左右的转变活化能为117.5koal/mol,这一数值与文献上PET/60PHB这个转变的活化能120kcal/mol相接近.文中还计算了共聚物在不同温度下的10s应力松弛模量,所得结果与实测值相吻合. 相似文献
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For two-phase polymer blend systems, the phase inversion will take place as the blendcomposition is changed. In this paper a mechanical model has been proposed to describe themodulus-composition relation in the phase inversion region. The application of the mechanicalmodel to two polyurethane blend systems has been studied. It was found that the theoreticalprediction for the modulus-composition relation is quite consistent with the experimentalresults. Furthermore, the characteristics of the phase inversion can be determined uniquelyby the parameters involved in the mechanical model. 相似文献
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本文首先研究了水-铈盐-丙烯腈系统在黑暗及有空气存在的条件下的聚合速度,指出水与铈盐生成HO·基的反应不一定必须通过光能的吸收。与Mino的报导不同,在研究水-铈盐-丙烯脯-纤维素系统中的接聚反应时发现,虽然在很大程度上改变反应条件,均聚物总是会生成的。这说明,纤维素的加入并不能抑制水-铈盐-丙烯腈系统中所固有的均聚反应。因此,Mino的接聚系统中实际上存在着二个氧化还原系统,即铈盐-纤维素与水-铈盐,前者能产生纤维素大分子自由基而接聚,后者能生成HO·低分子自由基而均聚。由于Mino没有充分考虑到后者,所以他对反应机理的描述,是不够全面的。 在研究了该系统均聚反应的基础上,我们提出了把引发和接聚分离进行,并在单体汽相中接枝,使均聚物生成量大为减少,这在反应时间延长时表现得更为显著。 我们还研究了强力粘胶帘子綫在接聚丙烯腈后的纤维性貭。实验表明变性纤维在耐光、耐腐、抗化学试剂、湿态强度等性能方面有很大改善。 相似文献