Self-Reinforced Cellulosic Nanocomposites: Processing Optimization and Interface Characterization of Hemp Cellulose Matrix Reinforced With Cellulose Nanocrystals

Abstract

This study investigates the development of self-reinforced nanocomposites utilizing hemp-derived cellulose as both matrix and reinforcement phases. Cellulose nanocrystals (CNCs) with an aspect ratio of similar to 19 (191.1 +/- 52.4 nm length, 10.1 +/- 2.1 nm diameter) were isolated from hemp fibers and incorporated as nanoscale reinforcement into a hemp cellulose matrix at loadings of 1-15 wt%. The nanocomposite processing was optimized using water-based dissolution to eliminate toxic solvents while maintaining composite performance. Mechanical characterization revealed optimal reinforcement efficiency at 10 wt% CNC loading, achieving a 161% increase in tensile strength (from 20.77 to 54.15 +/- 1.05 MPa) compared to the unreinforced matrix. The reinforcement mechanism was characterized through Fourier transform infrared (ATR-FTIR) spectroscopy, revealing enhanced hydrogen bonding at the CNC-matrix interface. X-ray diffraction analysis confirmed increased crystallinity in the nanocomposites, while thermogravimetric analysis demonstrated improved thermal stability. Polarimetric analysis revealed CNC-induced changes in optical anisotropy, indicating effective nanoparticle dispersion. The optimized nanocomposite exhibited mechanical properties comparable to solvent-processed systems while demonstrating the viability of source-identical reinforcement strategies in natural polymer composites. This self-reinforced approach provides insights into interface engineering and load transfer mechanisms in cellulosic nanocomposite systems.