Toward flexible electronics: A novel polyurethane integrating self-healing, UV-protective, reprocessable, and degradable properties

Flexible electronics are striving in modern society, and they impose harsh and urgent requirements for flexibility on electronic package substrates. However, traditional materials, including ceramics, metals, or polymers are lack of flexibility. Herein, a polyurethane named PU-D1Q1VF1 is proposed via incorporating carefully selected biobased units and synergistic dynamic bonds, and the PU-D1Q1VF1 not only meets the basic requirements of flexibility but also possesses properties of self-heal, UV-protection, reprocessability, and degradability. The polycaprolactone diol (PCL diol) was employed as the soft segment, and the bis(2-hydroxyethyl) disulfide (HEDS) and lignin derived model monomer hydroquinone were selected as chain extenders. Moreover, carefully synthesized bio-based monomer (E)-4-(((furan-2-ylmethyl)imino)methyl)-2-methoxyphenol (VF) was used as the capping agent, which could facilitate the self-healing process of the PU-D1Q1VF1.