• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Polymer Bulletin >A new extra situ sol–gel route to silica/epoxy (DGEBA) nanocomposite. A DTA study of imidazole cure kinetic
【24h】

A new extra situ sol–gel route to silica/epoxy (DGEBA) nanocomposite. A DTA study of imidazole cure kinetic

机译：二氧化硅/环氧树脂（DGEBA）纳米复合材料的新的原位溶胶-凝胶法。咪唑固化动力学的DTA研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Silica nanoparticles were obtained through the Stöber method, from mixtures of tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTS). The nanoparticles were dispersed in tetrahydrofuran (THF) and coupled to bisphenol A epoxy resin (DGEBA) through surface amino groups. After removing THF non-isothermal cure was performed at different heating rates (2–20°C/min), using imidazole (2–4 wt%) as curing agent. For the sake of comparison bare DGEBA epoxy polymers were also prepared with similar schedule A nanocomposite of well-dispersed silica nanoparticles (5 wt%) in a fully cured epoxy matrix was easily obtained. Lower cure kinetics were observed with silica addition. This was attributed to reduction of the imidazole volume concentration. Cure activation energy was not influenced by silica presence, whereas it changed with the imidazole content. Therefore, experimental results suggested that silica had only an indirect effect (the reduction of the imidazole molar concentration) on the epoxy matrix cure kinetics. Glass transformation temperatures, T g, as high as 175°C were recorded. The nanocomposite glass transformation temperature depended on the heating rate of the cure process, the imidazole and silica content. T g changes as high as 40°C were detected as a function of the heating rate. At higher imidazole content no differences in T g values between bare polymer and the nanocomposite were observed. This suggests that a higher imidazole content assures a better interconnection between the compatibilizing epoxy shell around the nanoparticles and the epoxy matrix. The new proposed methodology is an easy route to engineer both nanocomposites structure and interfacial interactions, thus tailoring their properties.
机译：二氧化硅纳米粒子是通过Stöber方法从四乙氧基硅烷（TEOS）和3-氨丙基三乙氧基硅烷（APTS）的混合物中获得的。纳米颗粒分散在四氢呋喃（THF）中，并通过表面氨基与双酚A环氧树脂（DGEBA）偶联。除去THF后，以咪唑（2-4 wt％）作为固化剂，以不同的加热速率（2-20°C / min）进行非等温固化。为了进行比较，还以相似的时间表制备了裸露的DGEBA环氧聚合物。在完全固化的环氧基质中，容易获得分散良好的二氧化硅纳米颗粒（5 wt％）的纳米复合材料。加入二氧化硅后观察到较低的固化动力学。这归因于咪唑体积浓度的降低。固化活化能不受二氧化硅存在的影响，而随咪唑含量的变化而改变。因此，实验结果表明二氧化硅仅对环氧基质固化动力学具有间接作用（降低咪唑摩尔浓度）。记录的玻璃化转变温度T g 高达175℃。纳米复合玻璃的转变温度取决于固化过程的加热速率，咪唑和二氧化硅的含量。根据加热速率，检测到高达40°C的T g 变化。在较高的咪唑含量下，未观察到裸聚合物和纳米复合材料之间的T g 值存在差异。这表明较高的咪唑含量可确保纳米颗粒周围的相容性环氧壳层与环氧基质之间的互连性更好。新提出的方法学是设计纳米复合材料的结构和界面相互作用的简便方法，从而可以调整其性能。

著录项

  • 来源
    《Polymer Bulletin》 |2011年第9期|p.1289-1300|共12页
  • 作者

    F. Branda; F. Tescione; V. Ambrogi; D. Sannino; B. Silvestri; G. Luciani; A. Costantini;

  • 作者单位

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

    Department of Materials and Production Engineering, University of Naples Federico II, Piazzale Tecchio, 80-80125, Naples, Italy;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    Silica-epoxy nanocomposites; Non-isothermal cure kinetic; Nanocomposite structure;

    机译：二氧化硅-环氧纳米复合材料;非等温固化动力学;纳米复合结构;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号