A Comparison of Phase Organization of Model Segmented Polyurethanes with Different Intersegment Compatibilities
A Comparison of Phase Organization of Model Segmented Polyurethanes with Different Intersegment Compatibilities
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DOI：
10.1021/ma8014454
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发表时间：
2008-12-23
期刊：
影响因子：
5.5
通讯作者：
Runt, James
中科院分区：
文献类型：
--
作者：
Hernandez, Rebeca;Weksler, Jadwiga;Runt, James
合成了三个系列的化学定义明确的聚氨酯具有相同的硬段，但不同的软段化学感兴趣的生物医学应用。多嵌段聚氨酯具有由脂肪族聚碳酸酯[聚（1，6-己基1，2-乙基碳酸酯）]、聚四亚甲基氧化物或聚六亚甲基氧化物和羟基封端的聚（二甲基硅氧烷）的混合大分子二醇组成的软链段和相同的硬链段化学[4，4 ′-亚甲基二苯基二异氰酸酯和1，4-丁二醇]。使用小角X射线散射和其他方法的分析表明，三个系列的共聚物之间的硬链段和软链段的分层变化很大。例如，基于PDMS/PHMO的共聚物表现出三相、核-壳形态，而其他两个系列表现出典型的两相结构。除了定量测量的硬/软段分层的两相共聚物，FTIR光谱被用来评估间和组分内的氢键，和轻敲模式AFM被用来表征的纳米级形态。
Three series of chemically well-defined polyurethanes were synthesized with the same hard segments but different soft-segment chemistries of interest in biomedical applications. The multiblock polyurethanes have soft segments composed of either an aliphatic polycarbonate [poly(1,6-hexyl 1,2-ethyl carbonate)], polytetramethylenoxide, or a mixed macrodiol of polyhexamethylenoxide and hydroxyl-terminated poly(dimethylsiloxane) and the same hard-segment chemistry [4,4'-methylenediplienyl diisocyanate and 1,4-butanediol]. Analysis using small-angle X-ray scattering and other methods demonstrates that demixing of the hard and soft segments varies greatly between the three series of copolymers. For example, the PDMS/PHMO-based copolymers exhibit a three-phase, core-shell morphology, while the other two series exhibit a typical two-phase structure. In addition to quantitative measurements of hard/soft-segment demixing for the two-phase copolymers, FTIR spectroscopy was used to assess inter- and intracomponent hydrogen bonding, and tapping mode AFM was used to characterize the nanoscale morphology.