Mechanical Properties of Cellulose Nanofibril-Filled Polypropylene Composites


  • Han-Seung Yang
  • Douglas J. Gardner


Cellulose nanofiber, microfibrillated cellulose, microcrystalline cellulose, tensile strength, plastic deformation, flexural strength


Cellulose nanofiber (CNF), microfibrillated cellulose (MFC), and microcrystalline cellulose (MCC) filled-polypropylene (PP) composite samples were manufactured using a melt mixing technique. Mechanical testing was conducted to investigate tensile and flexural properties of the composites at different filler loading levels. Test results showed that in the case of cellulose nanofibril fillers, the composites sustained considerable tensile strength up to 10% (w/w) filler loading whereas the tensile strength of the MCC-filled composites decreased continuously. Moreover, tensile modulus increased as filler loading increased for all cellulose fillers. CNF and MCC-filled composites demonstrate plastic deformation and longer elongation at break than MFC-filled composites while MFC-filled composites exhibited a quasi-brittle behavior under tensile deformation. Flexural strength of cellulose nanofibril-filled composites decreased slightly as a function of filler loading up to 6% (w/w) and increased beyond 6% (w/w). The 10% (w/w) cellulose nanofibril-filled composite samples exhibited sustained flexural strength as compared with neat PP. The trend of increased flexural modulus of elasticity behavior was identical to the tensile modulus of elasticity behavior.


Amash A, Zugenmaier P (2000) Morphology and properties of isotropic and oriented samples of cellulose fibre-polypropylene composites. Polymer 41(4):1589-1596.nFolkes M (1985) Short fibre reinforced thermoplastics. John Wiley & Sons Ltd., Herts, UK. 151 pp.nJoseph PV, Joseph K, Thomas S (1999) Effect of processing variables on the mechanical properties of sisal-fiber-reinforced polypropylene composites. Compos Sci Technol 59(11):1625-1640.nOksman K, Clemons C (1998) Mechanical properties and morphology of impact modified polypropylene-wood flour composites. J Appl Polym Sci 67(9):1503-1513.nOksman K, Mathew AP, Bondeson D, Kvien I (2006) Manufacturing process of cellulose whiskers/polylactic acid nanocomposites. Compos Sci Technol 66(15):2776-2784.nPremalal HGB, Ismail H, Baharin A (2002) Comparison of the mechanical properties of rice husk powder filled polypropylene composites with talc filled polypropylene composites. Polym Test 21(7):833-839.nQiu W, Mai K, Zeng H (2000) Effect of silane-grafted polypropylene on the mechanical properties and crystallization behavior of talc/polypropylene composites. J Appl Polym Sci 77(13):2974-2977.nRana AK, Mandal A, Mitra BC, Jacobson R, Rowell R, Banerjee AN (1998) Short jute fiber-reinforced polypropylene composites: Effect of compatibilizer. J Appl Polym Sci 69(2):329-338.nRijsdijk HA, Contant M, Peijs AAJM (1993) Continuous-glass-fibre-reinforced polypropylene composites: I. Influence of maleic-anhydride-modified polypropylene on mechanical properties. Compos Sci Technol 48(1-4): 161-172.nSanadi AR, Caulfield DF, Jacobson RE, Rowell RM (1995) Renewable agricultural fibers as reinforcing fillers in plastics: Mechanical properties of Kenaf fiberpolypropylene composites. Ind Eng Chem Res 34(5): 1889-1896.nSiqueira G, Bras J, Dufresne A (2009) Cellulose whiskers versus microfibrils: Influence of the nature of the nanoparticle and its surface functionalization on the thermal and mechanical properties of nanocomposites. Biomacromolecules 10(2):425-432.nWambua P, Ivens J, Verpoest I (2003) Natural fibres: Can they replace glass in fibre reinforced plastics? Compos Sci Technol 63(9):1259-1264.nYang HS, Gardner DJ (2011) Morphological characteristics of cellulose nanofibril-filled polypropylene composites. Wood Fiber Sci (In Press).nYang HS, Kim HJ, Park HJ, Lee BJ, Hwang TS (2007) Effect of compatibilizing agents on rice-husk flour reinforced polypropylene composites. Compos Struct 77(1): 45-55.nYang HS, Kim HJ, Son J, Park HJ, Lee BJ, Hwang TS (2004) Rice-husk flour filled polypropylene composites; mechanical and morphological study. Compos Struct 63 (3-4):305-312.n






Research Contributions