Scholarlink

<p>The effect of carbon nanoparticles on the aging processes of several polyimide (PI) systems has been investigated using thermogravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), mechanical testing and scanning electron microscopy. The novelties of this study include the detailed analysis of the dynamics of changes in the mechanical properties caused by thermal aging, which revealed a slower rate of the aging processes in nanocomposite films compared to that of the unfilled films. It was demonstrated for the first time that the introduction of carbon nanoparticles leads to a slower reduction in the strength and ultimate deformation of the films under thermal aging conditions. For example, at 450 ˚C the tensile stress of PMDA-ODA/nanocarbon composite films decreased to 50% of their initial value within approximately 90&#xa0;min. This rate is about 1.5 times slower than of the control PMDA-ODA film, which took 60&#xa0;min to reach the same reduction. The results of isothermal TGA showed that the introduction of carbon nanoparticles led to an increase in the activation energy of the aging processes in PI-based composites by up to 1.5 times, depending on the type and concentration of nanofillers, compared with the values for unfilled films. The activation energy of the aging processes was calculated as 89&#xa0;kJ/mol for the R-ODA, 155&#xa0;kJ/mol for PMDA-ODA, and for the composite films: 225&#xa0;kJ/mol (PMDA-ODA/2% CNT), 191&#xa0;kJ/mol (PMDA-ODA/5% CNF), 127&#xa0;kJ/mol (R-ODA/2% CNT), and 134&#xa0;kJ/mol (R-ODA/5% CNF). Using FTIR spectroscopy, it was found that the presence of nanocarbon in the PI systems enhances the intermolecular interactions between the PI chains (including π-π interactions), which may explain the increased stability of the composites during heat treatment.</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

The role of carbon nanofillers in the aging processes of polyimide composites

  • 期刊论文

  • 发表日期：

    2025年6月14日

查看全文
  • Igor Kuntsman,
  • Alexandra Nikolaeva,
  • Andrei Didenko,
  • Elena Vlasova,
  • Elena Ivan’kova,
  • Iosif Gofman,
  • Sergey Larin

摘要

The effect of carbon nanoparticles on the aging processes of several polyimide (PI) systems has been investigated using thermogravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), mechanical testing and scanning electron microscopy. The novelties of this study include the detailed analysis of the dynamics of changes in the mechanical properties caused by thermal aging, which revealed a slower rate of the aging processes in nanocomposite films compared to that of the unfilled films. It was demonstrated for the first time that the introduction of carbon nanoparticles leads to a slower reduction in the strength and ultimate deformation of the films under thermal aging conditions. For example, at 450 ˚C the tensile stress of PMDA-ODA/nanocarbon composite films decreased to 50% of their initial value within approximately 90 min. This rate is about 1.5 times slower than of the control PMDA-ODA film, which took 60 min to reach the same reduction. The results of isothermal TGA showed that the introduction of carbon nanoparticles led to an increase in the activation energy of the aging processes in PI-based composites by up to 1.5 times, depending on the type and concentration of nanofillers, compared with the values for unfilled films. The activation energy of the aging processes was calculated as 89 kJ/mol for the R-ODA, 155 kJ/mol for PMDA-ODA, and for the composite films: 225 kJ/mol (PMDA-ODA/2% CNT), 191 kJ/mol (PMDA-ODA/5% CNF), 127 kJ/mol (R-ODA/2% CNT), and 134 kJ/mol (R-ODA/5% CNF). Using FTIR spectroscopy, it was found that the presence of nanocarbon in the PI systems enhances the intermolecular interactions between the PI chains (including π-π interactions), which may explain the increased stability of the composites during heat treatment.