在玻璃转变温度及其以上温区聚苯乙烯/聚氧化乙烯共混物的动力学弛豫行为

用熔融共混法制备了不同组分的聚苯乙烯(PS)与聚氧化乙烯(PEO)共混物(PS/PEO).在玻璃转变温度T_g及其以上温区,利用相对能量耗散技术研究了该共混物的动力学行为.结果发现,在能量耗散-温度曲线上出现了两个弛豫型的耗散峰(α峰和α′峰).分析表明,α峰是与PS玻璃转变有关的特征耗散峰; α′峰则对应于一种“液-液转变”.两者的弛豫时间τ都不满足Arrhenius关系.此外,还研究了组分对这两个弛豫型耗散峰的影响,并给予了定性的解释. 关键词： 相对能量耗散 玻璃转变 力学弛豫

Dynamic relaxation of polystyrene/poly(ethylene oxide) blends above glass transition temperature

A series of blends with different compositions were prepared by melt-mixing on the basis of polystyrene and poly(ethylene oxide). Using the relative energy dissipation method, the dynamic behavior of the blends above the glass transition temperature was investigated. Two relaxational dissipation peaks (α and α′) were observed. It is suggested that peak α is associated with the glass transition of polystyrene and peak α′ with the liquid-liquid transition. The relaxation time τ of both relaxations does not satisfy the Arrhenius law. The effect of composition on the dynamic relaxation of the blends were also discussed qualitatively.