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TRANSITION POINTS OF POLYMERS

机译：聚合物的转变点

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As a model for polymers, the pseudocrosslink of various sizes is proposed. The size of links, lengths of connected chains, and the times tau's for their translation or relaxation are derived. According to the size, four transition temperatures (T's) are proposed such as the linking for the smallest size A (T-A), that for the largest one B (T-B), the melting point (T-m), and the glass transition point (T-g). The equation for T-g is derived with an assumption that the cooling time t is equal to the relaxation time of the segment at T-g and T-g is found to be about 50 degrees C higher than T-A. T-g decreases with t. T-B is twice as much as T-A. T-g/T-B is 2/3 in the general case and 1/2 for hindered polymers. T-m is very close to T-B, but somewhat lower than it when the cohesion heat is large. Related problems are discussed: The thermal expansion coefficient above T-g is about 1/10 T-g. The rebound resilience of rubber at temperature T is given by a ratio of(T - T-g)/(T - T-A) The sound velocities in glassy plastics and rubber are 2000 and 50-100 m/s, respectively, depending on the elasticity. The temperature-shift factor for the stress-relaxation spectrum is derived directly from the equation for the relaxation time without use of the thermal expansion coefficient. (C) 1995 John Wiley and Sons, Inc. [References: 35]
机译：作为聚合物的模型，提出了各种尺寸的假交联。得出链接的大小，连接的链的长度以及tau的平移或松弛时间。根据尺寸，提出了四个转变温度（T's），例如最小尺寸A（TA），最大尺寸B（TB），熔点（Tm）和玻璃化转变温度（Tg）的连接。 ）。假设冷却时间t等于T-g处的段的松弛时间，并且得出T-g比T-A高约50摄氏度，则得出T-g的方程。 T-g随t减小。 T-B是T-A的两倍。 T-g / T-B通常为2/3，受阻聚合物为1/2。 T-m非常接近T-B，但是当内聚热很大时，它比T-B稍低。讨论了相关的问题：高于T-g的热膨胀系数约为1/10 T-g。橡胶在温度T下的回弹弹性由（T-T-g）/（T-T-A）之比给出。玻璃纤维和橡胶中的声速取决于弹性，分别为2000和50-100 m / s。应力松弛谱的温度漂移因子是直接从松弛时间方程导出的，而无需使用热膨胀系数。 （C）1995 John Wiley and Sons，Inc. [参考：35]

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