Thermal programming of triple-shape-memory epoxy with flexible segments and Diels-Alder networks

作者：Wan, Liying; Yan, Meiling^*; Wang, Jianhong; Liu, Xianglong; Huang, Juntong; Yang, Hao; Kong, Xinming

来源：IRANIAN POLYMER JOURNAL, 2024, 33(1): 93-103.

DOI：10.1007/s13726-023-01235-z

• Triple-shape memory
• Epoxy
• Diels-Alder reaction
• Soft segment
• Glass transition temperature

This study reports the innovative preparation of triple-shape-memory epoxy resin (EP-DA) through thermal programming. Flexible poly(propylene glycol) diglycidyl ether (PEGDE) segments and reversible Diels-Alder (DA) dynamic covalent bonds were introduced into epoxy resin through molecular structural design, controlling glass transition temperature (Tg) and DA reaction temperature, respectively, which then was used as the two reversible switches of EP-DA. FTIR results verified that PEGDE and DA bond were successfully brought in EP-DA network. DSC and TG tests were used to demonstrate the three stages of EP-DA thermal behavior: Tg, DA thermal reversible reaction temperature and thermal degradation temperature. Bending-recovery test verified the dual-shape-memory, and DMA test verified the excellent triple-shape-memory of EP-DA. The general elastic deformation, high elastic deformation and flow deformation of EP-DA molecular segments revealed its shape-memory mechanism. Furthermore, when PEGDE content increased, Tg, crosslinking density of EP-DA, fixity ratio and strength decreased, toughness increased, and recovery rate as well as recovery speed were promoted. The thermal reversibility of DA bonds in EP-DA also endues it with retrievability and self-reconstruction.

• 单位
  南昌航空大学