研究了同时具有最高临界互溶温度和最低临界互溶温度的羧化聚苯醚／聚苯乙烯共混体系随退火温度的变化而发生的相形态结构的变化．研究了此共混体系的相分离机理．并发现了此特殊共混体系低温和高温区的相分离机理是不同的．从分子的结构和分子间特殊相互作用上探讨了此共混体系产生特殊相行为的原因． The change of morphology of the carboxylated poly (phenylene ether) / polystyrene blend system with the highest critical miscibility temperature and the lowest critical miscibility temperature with the annealing temperature was studied. The phase separation mechanism of this blends was studied. It was found that the mechanism of phase separation of low temperature and high temperature region of this particular blend was different. The reasons for the special phase behavior of this blends were discussed from the molecular structure and intermolecular interactions.