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首页> 外文期刊>Polymer: The International Journal for the Science and Technology of Polymers >Synthesis and characterization of organosiloxane modified segmented polyether polyurethanes
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Synthesis and characterization of organosiloxane modified segmented polyether polyurethanes

机译：有机硅氧烷改性的嵌段聚醚聚氨酯的合成与表征

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摘要

Segmented polyurethanes derived from a 1000 (M) over bar(n), hydroxyl terminated polytetramethylene oxide soft segment, 4,4'-methylene diphenyl diisocyanate. MDI, and 1,4-butanediol were modified with a 1200 (M) over bar(n) secondary aminoalkyl functional polydimethylsiloxane (PDMS) oligomer via solution polymerization in tetrahydrofuran (THF)/dimethylacetamide (DMAC). Various compositions were studied using FTIR and NMR spectroscopy, thermal analysis, quantitative size exclusion chromatography (SEC), cone calorimetry, transmission electron microscopy, XPS and mechanical testing. The results suggest that, with as little as 15% of the polydimethylsiloxane one may reduce the cone calorimetry heat release rate by a factor of about 2/3 and hence improve fire resistance, while maintaining mechanical behavior. It is suggested that the low surface energy characteristics of PDMS promote migration to the air-polymer interface to form a predominately PDMS enriched surface. The latter is oxidized at elevated temperatures in air to a silicate-like material and this serves as a protective layer, which further reduces burning of the underlying polyurethane. Dynamic mechanical behavior and electron microscopy suggest that a complex mutiphase structure is produced, particularly at low PDMS weight fractions. (C) 2000 Elsevier Science Ltd. All rights reserved. [References: 21]
机译：由1000（M）bar（n）以上的嵌段聚氨酯，羟基封端的聚四亚甲基氧化物软链段，4,4'-亚甲基二苯基二异氰酸酯。通过在四氢呋喃（THF）/二甲基乙酰胺（DMAC）中进行溶液聚合，在bar（n）仲氨基烷基官能聚二甲基硅氧烷（PDMS）低聚物上用1200（M）改性MDI和1,4-丁二醇。使用FTIR和NMR光谱，热分析，定量尺寸排阻色谱（SEC），锥形量热法，透射电子显微镜，XPS和机械测试研究了各种成分。结果表明，低至15％的聚二甲基硅氧烷可使锥体量热法的放热量降低约2/3，从而提高耐火性，同时保持机械性能。建议PDMS的低表面能特性促进向空气-聚合物界面的迁移，从而形成主要是PDMS富集的表面。后者在升高的温度下在空气中被氧化成类似硅酸盐的材料，并作为保护层，进一步减少了底层聚氨酯的燃烧。动态力学行为和电子显微镜表明，会产生复杂的多相结构，尤其是在低PDMS重量分数的情况下。 （C）2000 Elsevier ScienceLtd。保留所有权利。 [参考：21]

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