Plant-derived biopolymers are renewable and readily available, thus making viable alternatives to synthetic polymers. The present study examined properties of biopolymers from cover crops such as rye, oat, clover, vetch, and barley, which were grown organically in a greenhouse. The yields of cellulose, hemicellulose, and lignin of the cover crops were calculated based on the dry weight. Structural variations and thermal properties of the isolated cellulose were characterized and compared with commercial cellulose using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and Thermogravimetric analysis (TGA). The average yield percentages of cellulose, hemicellulose, and lignin were 19 to 27%, 9 to 25%, and 1.42 to 4.86%, respectively. The FTIR and Raman spectral analysis indicated that the isolated cellulose had similar peaks and patterns to commercial cellulose, and confirmed the removal of non-cellulosic constituents. The onset decomposition temperature occurred at 270 °C in all samples. Interestingly, the maximum degradation temperature beyond 370 °C in cellulose was isolated from black oat, which was higher than commercial cellulose (350 °C). The findings of this research suggest that cellulose isolated from cover crops may be a benefit to the polymer industry in the development of bio-based materials such as biofuels, bio-composites, and biomedical devices.

In this study, agricultural residue from black oat, a cover crop usually grown to improve soil nutrients between the periods of regular crop production, was used as a source of cellulose fibers. Concentrations of 1, 3, and 5 wt. % of regenerated cellulose (RC) fibers blended in poly(vinyl alcohol) (PVA) solution were used to prepare the reinforced composite films (CFs) by the solvent cast method. Compared to neat PVA film (control), the effects of RC addition on functional properties of CFs, such as water absorption, transparency, thermal stability, and mechanical property were investigated. All CFs with different RC concentrations exhibited improved mechanical property and thermal stability while the swelling property was decreased, and no significant changes were observed in the film transparency as compared with the control film. Among the CFs, films with 3% RC significantly decreased water vapor transmission rate, swelling, and soluble fraction (p < 0.05). In addition, Young’s modulus and tensile strength were increased by 40 MPa and 3 MPa, respectively, while elongation at break was decreased by 4%, compared to the control film. The results indicate that RC from black oat might be feasible as potential bio fillers to improve film properties in a bio-based composite matrix.