The thermal self-healing properties of phenolic polyurethane derived from polyphenols with different substituent groups

Phenolic hydroxyl gave thermal self-healing ability to phenolic polyurethanes in our previous study. To explore, the feasibility of preparing self-healing polyurethanes through polyphenols with different substituents. Urushiol, propyl gallate, catechol, and tert-butylhydroquinone were chosen for preparation of four phenolic polyurethanes, and the different factors at the structures of these polyphenols worked together led the different properties and self-healing ability. The peak temperatures of these four polyurethanes were determined by DSC in the following order: PTHFTDI-Urushiol < PTHFTDI-Catechol < PTHFTDI-Propyl gallate < PTHFTDI-Tert-butylhydroquinone. Variable-temperature FT-IR spectra displayed that PTHFTDI-Propyl gallate with electron-withdrawing substituent exhibited the lowest decomposition and healing temperatures. Meanwhile, based on TGA analysis, lower decomposition temperature suggested lower thermostability; and PTHFTDI-Urushiol with electron-donating substituent exhibited the best thermostability. At the same temperature, the healing abilities of the three polyurethanes were ranked as follows: PTHFTDI-Catechol < PTHFTDI-Urushiol < PTHFTDI-Propyl gallate. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47039.