PPO-PDMS-PHS_n三元多嵌段共聚物的形态结构和性能

Morphology and Properties of PPO - PDMS-PHS_n Segmented Ternary Copolymers

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的形态结构和性能进行了研究.结果表明,(?)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tanδ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.

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 tanδ 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.