Download (PDF 587 KB): https://research.fs.usda.gov/download/treesearch/52859.pdf
Abstract
There is growing interest in developing bio-based materials for packaging. Bio-derived materials such as cellulose nanocrystals (CNCs) and poly(lactic acid) (PLA) can be used to develop sustainable packaging applications. Incorporating CNCs into PLA can increase the crystallinity and barrier properties of PLA. The challenge lies in both increasing the flexibility of PLA and in obtaining good dispersion of the CNCs. This study proposes a novel chemical modification of cellulose nanocrystals (CNCs) to potentially improve the dispersion and adhesion of CNCs in the poly(lactic acid) (PLA) matrix using sustainable chemistries. Long chain hyrdrocarbon structure of vegetable oil methyl ester (CME) was grafted onto CNCs to produce the CNC fatty acid methyl ester (CNCFE). Transesterification was successful as indicated by Fourier transform infrared (FTIR) spectroscopic analysis. CNCFE nanocrystals showed improved thermal stability as compared to unmodified CNCs and CME samples. This could broaden the thermal processing window for nanocomposites of PLA/CNC. For the PLA/CNCFE nanocomposites, better dispersion of CNCFE nanocrystals into PLA matrix was observed and enhanced compatibility between nanocrystals and PLA matrix were achieved. Tensile test results indicated higher Young’s modulus nanocomposites by incorporation of 5% CNCFE as compared to unmodified CNCs. The results provide practical and fundamental interest in the PLA/CNC nanocomposites to be manufactured for packaging film via melt-processing. In this paper, perspectives for future research are discussed as well.
Citation
Wei, Liqing; Stark, Nicole M.; Sabo, Ronald C.; Matuana, Laurent. 2016. Modification of cellulose nanocrystals (CNCs) for use in poly(lactic acid) (PLA)-CNC composite packaging products. In: Proceedings, Forest Products Society International Convention28-29 June 2016. Portland, OR. Madison, WI, Forest Products Society. 6 p.
