Synthesis and characterization of graphene nanoplatelets-hydroxyethyl cellulose copolymer-based polyurethane bionanocomposite system.

Bionanocomposites is an emerging class of biohybrid materials, have a significant impact in environmental and biomedical fields owing to their high performance, lightweight, unique, and ecofriendly properties. A major challenge in the multiphase bionanocomposites system is to subtle control over the performance by managing the individual properties of reacting components. Herein, we presented the preliminary investigation on bionanocomposite system based on graphene nanoplatelets (GNPs) and hydroxyethyl cellulose graft poly(lactic acid) copolymer-polyurethane (HLAC-PU) with the aim to understand the structure property correlation for proposed applications in electronics and medical areas. The HLAC was fabricated by graft copolymerization of hydroxyethyl cellulose (HEC) and lactic acid (LA) with dibutyltin dilaurate. The HLAC was used to get a bio-functionalized PU matrix reinforced with GNPs by step-growth polymerization method. The structural, surface, and thermal properties of the HLAC and GNPs-HLAC-PU bionanocomposites were studied. The spectroscopic techniques confirmed the structure of bionanocomposites by the identification of related bands. The SEM/EDX results demonstrated that the 0.3 wt% of GNPs dispersed well in the HLAC-PU matrix and offered higher crystallinity. The reinforcement of the 0.3 wt% of GNPs has meaningfully enhanced the thermal stability producing higher residue contents. The reinforced GNPs filler increased the water resistance of bionanocomposites by reducing their water vapor permeability.