Bi-soft segment polyurethane membranes: Surface studies by X-ray photoelectron spectroscopy
Bi-soft segment polyurethane membranes: Surface studies by X-ray photoelectron spectroscopy
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DOI：
10.1016/j.memsci.2006.03.037
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发表时间：
2006-09-15
影响因子：
9.5
通讯作者：
de Pinho, Maria Norberta
中科院分区：
文献类型：
--
作者：
Queiroz, Denise P.;do Rego, A. M. Botelho;de Pinho, Maria Norberta
通过基于聚环氧丙烷的三异氰酸酯封端预聚物（PU）与聚丁二烯二醇（PBDO）的反应合成了含有两个软链段（聚环氧丙烷）和聚丁二烯的聚氨酯膜。这些聚氨酯的软链段根据PBDO/PU比率的变化在本体中发生不同程度的相分离。通过 X 射线光电子能谱 (XPS) 对膜表面进行了研究。结果表明，表面富含PU。人们发现这种表面富集随着 PBDO 含量的增加而增加，因此随着两种软链段在本体中的混合而增加。此外，发现聚氨酯/脲硬链段表面的偏析在 PBDO/PU 等于 0.33 时达到最大值，并且随着 PBDO/PU 比率的增大而降低。具有最高的氨基甲酸酯/脲基团表面分离的膜呈现出最高的表面能值和最高的极性，证实了硬链段迁移到表面。 (c) 2006 Elsevier B.V 保留所有权利。
Polyurethane membranes containing two soft segments, poly(propylene oxide) and polybutadiene, were synthesized by the reaction of a polypropylene oxide-based tri-isocyanate-terminated prepolymer (PU) with a polybutadiene diol (PBDO). The soft segments of these polyuretharres are phase-separated in the bulk to different degrees according to the variation of the PBDO/PU ratio. The membrane surfaces were investigated by X-ray Photoelectron Spectroscopy (XPS). The results show that the surface is enriched in PU. This surface enrichment was found to increase with the increase of PBDO content and therefore, with the mixing of the two soft segments in the bulk. Moreover, segregation at the surface of urethane/urea hard segments was found to reach a maximum at PBDO/PU equal to 0.33 and to decrease for larger PBDO/PU ratio. The membrane with highest surface segregation of urethane/urea groups presents the highest value of surface energy and the highest polarity confirming the migration of the hard segments to the surface. (c) 2006 Elsevier B.V All rights reserved.