[-PPO-PDMS-PHS-]n三元多嵌段共聚物的形态结构和性能

利用DMA, TEM和SAXS对以聚苯醚(PPO)为硬段、聚对羟基苯乙烯(PHS)为半硬段和聚二甲基硅氧烷(PDMS)为软段的三元多嵌段共聚物[-PPO-PDMS-PHS-]n以三种嵌段相容相为连续相, PPO与PHS的相容相和PDMS相为两种分散相, 其tan δ随温度变化曲线在-100℃至200℃一直是一很高的平台, 并具有优异的力学性能, 较好地解决了含有机硅类嵌段共聚物强度低的弱点, 同时又保留了嵌段共聚物微相分离的特性。

Morphology and properties of [-PPO-PDMS-PHS-]n segmented ternary copolymers

The morphology and properties of [-PPO-PDMS-PHS-]n segmented ternary copolymers were investigated by DMA, TEM and SAXS techniques. It is shown that the continuous phase of [-PPO-PDMS-PHS-]n is the compatible phase composed of PDMS, PPO and PHS segments, and that there exist two dispersed phases, i, e. the PDMS phase and a mixed phase of half hard (PHS) and hard (PPO) segments. The tan δ vs.T curve of the segmented ternary copolymer with 66.7% (W/W) PDMS shows a rather high plateau in the temperature range from -120℃ to 200℃, which indicates that the copolymer has the characteristics of microphase separation as well as compatibility of block copolymers, respectively. Meanwhile, it has good tensile properties, which means that [-PPO-PDMS-PHS-]n has overcome the weakness of low strength of block or segmented copolymers containing PDMS.