Self‐healing polymer materials have been developed rapidly over the past 20 years, which can replace thermosetting materials to a certain extent, repair damage without manual intervention, prolong service life, and compress usage cost. The self‐healing polymer materials derived from biomass resources can reduce the dependence on traditional non‐renewable resources such as petroleum. The structures and properties of biomass based self‐healing polymer materials are of great significance for their processing, recycling and self‐healing. In this paper, the research progress of bio‐based self‐healing polymer materials based on dynamic non‐covalent bonds and dynamic covalent bonds including hydroxyl ester, Schiff base, disulfide bond, and hydroxyl urethane derived from vegetable oil, lignin, cellulose, vanillin and natural rubber were reviewed, and the dynamic non‐covalent bonds and dynamic covalent bonds were also introduced. The applications of various dynamic covalent bonds and dynamic non‐covalent bonds in the design and construction of polymer materials were reviewed, and the future development of dynamic covalent polymer materials was prospected.
In order to improve the performance of phenolic foam, an additive compound of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and Itaconic acid (ITA) were attached on the backbone of ethyl cellulose (EC) and obtained DOPO-ITA modified EC (DIMEC), which was used to modify phenolic resin and composite phenolic foams (CPFs). The structures of DOPO-ITA were verified by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H NMR). The molecular structure and microstructure were characterized by FT-IR spectra and SEM, respectively. Compared with EC, the crystallinity of DIMEC was dramatically decreased, and the diffraction peak positions were basically unchanged. Additionally, thermal stability was decreased and Ti decreased by 24 °C. The residual carbon (600 °C) was increased by 25.7%. With the dosage of DIMEC/P increased, the Ea values of DIMEC composite phenolic resins were increased gradually. The reaction orders were all non-integers. Compared with PF, the mechanical properties, flame retardancy, and the residual carbon (800 °C) of CPFs were increased. The cell size of CPFs was less and the cell distribution was relatively regular. By comprehensive analysis, the suitable dosage of DIMEC/P was no more than 15%.
19 November 2021 in Journal of Polymers and the Environment