Enzymatically treated natural fibres as reinforcing agents for biocomposite material: mechanical, thermal, and moisture absorption characterization
The main goal of this research was to study how enzymatic treatment of hemp and flax fibres affects their utilization as reinforcement in polypropylene composites. Enzymes are environmentally benign, can be reused, and require mild operating conditions. The central hypothesis of this study is that the removal of hemicellulose and pectic fractions would reduce surface polarity resulting in fibres better suited for thermoplastic owing the reduction of hydroxyl groups distributed on the fibres surface. As a result, hemicellulases, pectinases, and a laccase were investigated. The removal of hemicellulose and pectic components using xylanase (with and without cellulase) and polygalacturonase, respectively, resulted in improved thermal properties and water resistance. The removal of up to 25 % (wt) of natural fibre did not significantly compromise the mechanical properties of the composite materials. This environmentally benign approach could be tailored to pretreat other feedstocks and optimized to cleave a specific amount of fibres for different composite applications.
KeywordsLignin Cellulase Hemicellulose Hemp Natural Fibre
The authors would like to acknowledge the financial support of Alberta Innovates Bio Solutions, Alberta Livestock and Meat Agency, as well as the Natural Sciences and Engineering Research Council of Canada. The authors are grateful to Alberta Innovates Technology Futures and Novozymes for supplying the materials needed for this study. The help for SEM imaging provided by Gayle Hatchard from the Department of Chemical and Materials Engineering at the University of Alberta is much appreciated.
This study was funded by Alberta Innovates Bio Solutions (Grant: AF 627).
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Conflict of interest
The authors declare that they have no conflict of interest.
- 8.Pommet M, Juntaro J, Heng JYY, Mantalaris A, Lee AF, Wilson K, Kalinka G, Shaffer MSP, Bismarck A (2008) Surface modification of natural fibers using bacteria: depositing bacterial cellulose onto natural fibers to create hierarchical fiber reinforced nanocomposites. Biomacromolecules 9:1643–1651CrossRefGoogle Scholar
- 21.Poletto M, Pistor V, Zattera A. Cellulose Fundamental Aspects- Chapter 2 (Structural characteristics and thermal properties of native cellulose), InTech, pp. 45–68Google Scholar