Fabricating robust soft-hard network of self-healable polyvinyl alcohol composite films with functionalized cellulose nanocrystals

Abstract In this study, conductive cellulose nanocrystals (CNCs) were coated with polypyrrole (PPy) using in situ chemical polymerization to form CNC-PPy conductive nano-network. The one-pot polymerization of “hard” segment methyl methacrylate (MMA) was continued onto above functionalized CNCs, then blended with “soft” molecular segment polyvinyl alcohol (PVA) to contain self-healing and conductive composite film (CPMV) fabricated by soft-hard network. In addition, the tensile strength of CPMV films with 2 wt% CNC-PPy was enhanced by 47.1%. Also, CPMV films exhibited self-healing properties due to the presence of hydrogen bonding dynamic network and showed sensitive resistance changes under external stimuli, which could be used to monitor various actions of the human body. Thus, the CPMV films present potential applications in electronic devices such as flexible electrodes, biosensors, and implantable devices.