Scholarlink

<p>A series of fluorinated copolyimides containing non-coplanar triphenylamine (TPA) units was synthesized from 4,4′-diamino-3′′,5′′-difluorotriphenylamine (DMTPA), 4,4′-oxydianiline (ODA), and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) through high-temperature polycondensation. The resulting copolyimides exhibited high thermal stability, good solubility in common organic solvents, optical transparency, and enhanced hydrophobicity. Wide-angle X-ray diffraction (WAXD) and molecular simulations confirmed that the bulky fluorinated TPA units increased interchain spacing and fractional free volume (FFV), thereby facilitating gas transport. Gas permeation measurements at 35&#xa0;°C and 4&#xa0;bar revealed that CO<sub>2</sub> permeability increased with TPA content, whereas CO<sub>2</sub>/N<sub>2</sub> selectivity remained nearly constant (~ 21). The best-performing membrane (DFPI-5) achieved a CO<sub>2</sub> permeability of 24.93 Barrer with a CO<sub>2</sub>/N<sub>2</sub> selectivity of 21.31, approaching the 2008 Robeson upper bound. These findings underscore the effectiveness of fluorinated, non-coplanar TPA moieties in tailoring polyimide membranes for advanced gas separation.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Synthesis, Characterization, and Gas Separation Properties of Polyimides Incorporating Fluorinated Non-coplanar Triphenylamine Units

  • 期刊论文

  • 发表日期：

    2025年10月7日

查看全文
  • Chao Shan,
  • Junhao Mo,
  • Shanshan Wu,
  • Junjie Qu,
  • Chanjuan Liu,
  • Xiaoyi Sun,
  • Xiaohua Huang

摘要

A series of fluorinated copolyimides containing non-coplanar triphenylamine (TPA) units was synthesized from 4,4′-diamino-3′′,5′′-difluorotriphenylamine (DMTPA), 4,4′-oxydianiline (ODA), and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) through high-temperature polycondensation. The resulting copolyimides exhibited high thermal stability, good solubility in common organic solvents, optical transparency, and enhanced hydrophobicity. Wide-angle X-ray diffraction (WAXD) and molecular simulations confirmed that the bulky fluorinated TPA units increased interchain spacing and fractional free volume (FFV), thereby facilitating gas transport. Gas permeation measurements at 35 °C and 4 bar revealed that CO2 permeability increased with TPA content, whereas CO2/N2 selectivity remained nearly constant (~ 21). The best-performing membrane (DFPI-5) achieved a CO2 permeability of 24.93 Barrer with a CO2/N2 selectivity of 21.31, approaching the 2008 Robeson upper bound. These findings underscore the effectiveness of fluorinated, non-coplanar TPA moieties in tailoring polyimide membranes for advanced gas separation.