In situ synthesis of biodegradable polymers using nanocrystalline and microfibrillated cellulose and lignin with no functionalization

Abstract

Lignocellulosic fibers can be fractionated in hemicellulose, cellulose and lignin. Cellulose and lignin are the two most abundant biopolymers on earth, and although widely used (pulp and paper industry, civil industry, etc.), their application can be increased, due to their great abundance. From cellulose, it is possible to extract microfibrillated cellulose (MFC) and nanocrystalline cellulose (CNC). In this project, it will be evaluated the use of MFC, CNC and lignin for the production of composites of poly (vinyl acetate) (PVAc), poly (caprolactone) (PCL) and poly (butylene-co-terephthalate) (PBAT). One of the highlights of this project is the use of CNC, MFC and lignin without any type of functionalization in the in situ polymerization, which would potentially simplify the process and reduce the price of the final product. In the case of PVAc, the emulsion polymerization will be carried out, where CNC, MFC or lignin will be dispersed in the aqueous phase before the polymerization. For the case of PCL, the ring-opening polymerization of caprolactone will be performed, using CNC as reinforcement and hydroxyl source in the ROP synthesis. It is expected to form a covalent chemical bond between the CNC and PCL. A computational code, able to predict the behavior of hydroxyl group of CNC in the ROP of caprolactone, will be also developed. The PCL-bonded CNC produced in this synthesis will be used as reinforcement in the production of PBAT composites by casting. It is expected that the PCL attached to the CNC will improve the dispersion of the CNC in the PBAT. The polymer will be characterized measuring molecular weights, viscosity, Zeta potential, particle size distribution, thermal and mechanical properties, microscopies and other analyzes, if necessary. (AU)