高等学校化学学报

高等学校化学学报 ›› 1993, Vol. 14 ›› Issue (5): 720.

• 研究论文 • 上一篇    下一篇

聚硅氧烷聚脲嵌段共聚物的TEM及SAXS研究

陈雷, 何向东, 余学海, 朱育平, 杨昌正   

  1. 南京大学化学系, 南京 210008
  • 收稿日期:1992-03-21 修回日期:1993-02-07 出版日期:1993-05-24 发布日期:1993-05-24
  • 通讯作者: 余学海
  • 基金资助:

    国家自然科学基金;中国科学院化学所高分子物理实验室资助课题

Studies on the Micromorphoiogy of Polysiloxane-Polyurea Segmented Copolymer Using TEM and SAXS

CHEN Lei, HE Xian-Dong, YU Xue-Hai, ZU Yu-Ping, YANG Chang-Zheng   

  1. Department of Chemistry, Nanjing University, Nanjing, 210008
  • Received:1992-03-21 Revised:1993-02-07 Online:1993-05-24 Published:1993-05-24

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摘要： 采用透射电子显微镜与小角X光散射分别研究了不同软、硬段分子量及软段极性对聚硅氧烷聚脲多嵌段共聚体系微相结构的影响。结果表明,增加软段分子量及硬段含量有利于聚硅氧烷与聚脲的相分离。将极性氰丙基引入聚硅氧烷后两相混合度明显改善,同时聚脲硬段粒径减小并趋于均一。在聚氰丙基甲基硅氧烷基体中增加聚脲含量及其分子量,则两相界面厚度也随之增大。

关键词: 聚硅氧烷, 聚脲, 相分离, 多嵌段共聚物

Abstract: The micromorphology of segmented polysiloxane-polyureas based on polydimethylsiloxane or polycyanopropyimethylsiloxane soft segments and semicrystalline methylene diphenylene diiso-cyanate and diethyleneamine hard segments was examined using transition electron microscopy(TEM) and small angle X-ray scattering (SAXS).Specimens for eletron microscopy studies were prepared by thin film casting.The spherical morphology was observed in all of the samples.The size of the hard domain of polycyanopropylsiloxane polyurea is smaller and more regular than that of polydimethylsiloxane polyurea.The micrcdomain spacings and the size of the poiyurea hard segment measured by TEMwere compared to the results calculated from SAXSdata.It is also found that there are two steps In the accumulation of the hard domains.At the first step, a few polyurea aggregate by hydrogen bond to form the ''fundamental particles".In the second step, these "fundamental particles" gathered up together further to form the hard mierodomains.The slower evaporation rates of the solvents caused the larger polyurea mierodomains.

Key words: Polysiloxane, Polyurea, Phase separation, Segmented copolymer

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