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首页> 外文期刊>Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites >Kinetics of relaxation and crystallization of poly(ethylene terephthalate)
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Kinetics of relaxation and crystallization of poly(ethylene terephthalate)

机译：聚对苯二甲酸乙二醇酯的弛豫和结晶动力学

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摘要

We study the kinetics of structural relaxation and crystallization of poly(ethylene terephthalate) (PET). It is demonstrated that the activation energy depends strongly on fictive temperature T_f. The dependence of the glass transition temperature T_g on the heating rate q~+ is investigated for samples that were previously cooled down at a rate q~- = 12.5 K/min. Angell et al. {M. Tatsumisago, B. Halfpap, J. Green, S. Lindsay, A. Angell, Phys, Rev. B 45 (1992) 10091} compare the thermal properties of many glasses to their 'fragility'. The dimensionless fragility is a measure of the dependence of the activation energy for spatial rearrangement on changes of structure. We define a parameter #alpha#, easily determinable from experimental, which is close to one for 'strong' substances and much larger for 'fragile' systems. According to the present measurements #alpha# is extremely large for polymers (i.e. this is a class of very fragile substances).
机译：我们研究了聚对苯二甲酸乙二醇酯（PET）的结构弛豫和结晶动力学。结果表明，活化能强烈取决于虚拟温度T_f。对于先前以速率q-＝ 12.5K / min冷却的样品，研究了玻璃化转变温度T_g对加热速率q +的依赖性。 Angell等。 {M. Tatsumisago，B.Halfpap，J.Green，S.Lindsay，A.Angell，Phys，Rev.B 45（1992）10091}将许多玻璃的热性能与其“易碎性”进行了比较。无量纲的脆性是用于空间重排的活化能对结构变化的依赖性的量度。我们定义了一个参数＃alpha＃，该参数很容易从实验中确定，对于“强”物质，该参数接近一个参数;对于“易碎”系统，该参数更大。根据目前的测量，＃alpha＃对于聚合物非常大（即，这是一类非常易碎的物质）。

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