Effect of the Onsager coefficient and internal relaxation modes on spinodal decomposition in the high molecular isotopic blend polystyrene/deutero‐polystyrene studied with small angle neutron scattering
Effect of the Onsager coefficient and internal relaxation modes on spinodal decomposition in the high molecular isotopic blend polystyrene/deutero‐polystyrene studied with small angle neutron scattering
复制标题
小角中子散射研究的 Onsager 系数和内部弛豫模式对高分子同位素共混物聚苯乙烯/氘代聚苯乙烯旋节线分解的影响
DOI：
10.1063/1.471262
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
T. Springer
中科院分区：
文献类型：
--
作者：
G. Müller;D. Schwahn;H. Eckerlebe;J. Rieger;T. Springer
用小角中子散射研究了同位素共混物氘代聚苯乙烯/聚苯乙烯（d-PS/PS）的临界混合物在12 K≤ Tc−T <$≤82 K温度范围内的早期亚稳分解。这个过程可以用两个静态结构因子之间的弛豫来描述，S（Q）代表在混合状态和发生相分离的温度下系统的平衡值。弛豫过程的时间演化由动力学结构因子L（Q，t）描述，L（Q，t）取决于混合物的动力学性质。研究表明，混合系统的静态结构因子也可以在亚稳分解早期状态的不稳定两相区域中确定。与较低分子量的d-PS/PS样品相比，发现Flory-Huggins参数的一致值，因此，较低的临界温度甚至小于相分离温度。
The early state of spinodal decomposition was studied by small angle neutron scattering in the critical mixture of the isotopic blend deutero‐polystyrene/polystyrene (d‐PS/PS) of equal molecular volume of 1.42×106 cm3/mol in a temperature range 12 K≤‖Tc−T‖≤82 K. This process can be described by the relaxation between two static structure factors, S(Q) representing the equilibrium values of the system in the mixed state and at the temperature where phase separation occurs. The time evolution of the relaxation process is described by the dynamical structure factor, L(Q,t) which depends on the dynamic properties of the mixture. It will be shown that the static structure factor of a mixed system can also be determined in the unstable two‐phase region during the early state of spinodal decomposition. Consistent values for the Flory–Huggins parameter were found in comparison with a lower molecular d‐PS/PS sample and, therefore, a lower critical temperature which was even smaller than the phase separation temper...