title: Effect of cellulosic fiber scale on linear and non-linear mechanical performance of starch-based composites.
abstract: Cellulosic nanofibers (NFs) from kenaf bast were used to reinforce glycerol plasticized thermoplastic starch (TPS) matrices with varying contents (0-10wt%). The composites were prepared by casting/evaporation method. Raw fibers (RFs) reinforced TPS films were prepared with the same contents and conditions. The aim of study was to investigate the effects of filler dimension and loading on linear and non-linear mechanical performance of fabricated materials. Obtained results clearly demonstrated that the NF-reinforced composites had significantly greater mechanical performance than the RF-reinforced counterparts. This was attributed to the high aspect ratio and nano dimension of the reinforcing agents, as well as their compatibility with the TPS matrix, resulting in strong fiber/matrix interaction. Tensile strength and Young's modulus increased by 313% and 343%, respectively, with increasing NF content from 0 to 10wt%. Dynamic mechanical analysis (DMA) revealed an elevational trend in the glass transition temperature of amylopectin-rich domains in composites. The most eminent record was +18.5°C shift in temperature position of the film reinforced with 8% NF. This finding implied efficient dispersion of nanofibers in the matrix and their ability to form a network and restrict mobility of the system.
authors.affiliation: The New Zealand Institute for Plant & Food Research Limited, 7608 Lincoln, New Zealand. Electronic address: Samaneh.Karimi@plantandfood.co.nz.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Karimi
authors.affiliation: Department of Wood and Paper Science and Technology, Faculty of Natural Resources, University of Tehran, P.O. Box 31585-43114, Karaj, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Abdulkhani
authors.affiliation: Laboratory of Biocomposite Technology, Institute of Tropical Forestry and Forest Products (INTROP), University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Paridah Md
authors.initials: PM
authors.lastname: Tahir
authors.affiliation: Grenoble Institute of Technology, The International School of Paper, Print Media and Biomaterials (PAGORA), CS10065, 38402 Saint Martin d'Hères Cedex, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Dufresne
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D055119:Elastic Modulus; D016014:Linear Models; D055595:Mechanical Phenomena; D057139:Nanofibers / Q000737:chemistry*; D017711:Nonlinear Dynamics; D013213:Starch / Q000737:chemistry*; D013718:Tensile Strength
chemical_list: D002482:Cellulose; D013213:Starch
keywords: Cellulose nanofibers; Dynamic mechanical analysis (DMA); Mechanical properties; Nanocomposites; Thermoplastic starch