Department of Chemical Engineering and Leuven Materials Research Center, Katholieke Universiteit Leuven, Willem de Croylaan 46, B-3001, Leuven, Belgium.
ACS Appl Mater Interfaces. 2011 Aug;3(8):3172-80. doi: 10.1021/am200669w. Epub 2011 Jul 21.
The effects of thermally reduced graphene sheets (TRG) on the phase separation in poly[(α-methyl styrene)-co-(acrylonitrile)]/poly(methyl-methacrylate) blends were monitored using melt rheology, conductivity spectroscopy, and electron microscopic techniques. The TRG were incorporated in the single-phase material by solution mixing. The composite samples were then allowed to phase separate in situ. The thermodynamics of phase separation have been investigated by monitoring the evolution of the storage modulus (G') as a function of temperature as the system passes through the binodal and the spinodal lines of the phase diagram. The phase separation kinetics were probed by monitoring the evolution of G' as a function of time at a quench depth well in the spinodal region. It was observed that TRG significantly influenced the phase separation temperature, the shape of the phase diagram and the rate of phase separation. The state of dispersion of TRG in the blends was assessed using electron microscopy and conductivity spectroscopy measurements. Interestingly, the composite samples (monophasic) were virtually insulators at room temperature, whereas highly conducting materials were obtained as a result of phase separation in the biphasic materials.
使用熔体流变学、电导率光谱学和电子显微镜技术监测了热还原石墨烯片（TRG）对聚[（α-甲基苯乙烯）-共-（丙烯腈）]/聚（甲基丙烯酸甲酯）共混物相分离的影响。TRG 通过溶液混合掺入单相材料中。然后使复合材料样品在原位相分离。通过监测系统通过相图的拐点线和旋节线时存储模量（G'）随温度的演化来研究相分离的热力学。通过在旋节线区域的过冷深度处监测 G'随时间的演化来探测相分离动力学。结果表明，TRG 显著影响相分离温度、相图的形状和相分离的速率。使用电子显微镜和电导率光谱学测量评估了 TRG 在共混物中的分散状态。有趣的是，复合样品（单相）在室温下几乎是绝缘体，而两相材料的相分离导致获得了高导电性材料。
