writer：Binbo Wang, Songqi Ma*, Xiwei Xu, Qiong Li, Tao Yu, Sheng Wang, Shifeng Yan*, Yanlin Liu*, Jin Zhu
keywords：Carbon fiber reinforced composites，Recycle，Degradation，Polyurethane thermosets，Acetal
source：期刊
specific source：ACS Sustainable Chemistry and Engineering
Issue time：2020年

Carbon fiber (CF) reinforced polyurethane (PU) composites have attracted increasing attention in recent years. It is still a challenge to recycle the CF reinforced composites, and there is no report on the recycling of CF from PU matrix. In this paper, for the first time, a readily recyclable CF reinforced PU composite was prepared based on a biobased acetal diol, 2-(4-hydroxy-3-methoxyphenyl)-1,3-dioxan-5-ol (HMDO). The acetal diol was synthesized from the lignin derivative vanillin and was used to react with hexamethylene diisocyanate trimer to prepare the PU thermoset (PU-HMDO). On account of the cleavable acetal groups, the PU-HMDO could be decomposed within 40 min in low-concentration acidic solution completely. In addition, the heterocyclic structures of acetal and isocyanurate resulted in excellent mechanical and thermal properties of PU-HMDO. The tensile strength was 68 MPa, the elongation at break was 7.9%, and the glass transition temperature (Tg) was 130 °C, which are comparable to those of a PU thermoset (PU-BPA) from commercially available diol bisphenol A (BPA). The thermal stability of PU-HMDO was even higher than that of PU-BPA. The PU-HMDO-based CF composite exhibited similar mechanical properties to the PU-BPA-based CF composite, and CF could be reclaimed with maintained microscale morphology, chemical structures, and mechanical properties under mild acid conditions. This work will open a door to develop readily recyclable PU-based CF composites.

论文链接：https://pubs.acs.org/doi/10.1021/acssuschemeng.0c02330