Document Type : Research Paper

Authors

1 Faculty of Natural Resources, Sari Agricultural Sciences and Natural Resources University

2 M.sc graduated, Department of Wood and paper, Faculty of Natural Resources, Sari Agricultural Sciences and Natural Resources University

Abstract

Current research was conducted to investigate the effect of thermal modification on practical properties of horn beam bark flour-polypropylene composites. Wood plastic composites were divided in two levels of control and thermal modification, both levels included of 4 groups in bark fillers; 10, 20, 30 and 40%. Test samples prepared with maleic anhydride-grafted polypropylene as coupling agent by injection molding method. According to the results, bark flour increased water absorption, tensile and bending modulus. High proportion of bark fillers declined mechanical strength. Thermal modification significantly improved physical and mechanical properties of composite. Using lignocellulosic material flour bark hornbeam, tensile modulus and flexural modulus of composite material background had the highest improvement. In comparison between mechanical properties, impact resistance by adding flour bark had the greatest decrease. Thermal modification by increasing the crystallity, hemicellulose degradation, loss of polarity, increased compatibility between the two phases and uniform distribution of bark fillers in polymers, increased mechanical resistance.

Keywords

Main Subjects

-Abe, K., and Yamamoto H., 2006. Change in mechanical interaction between cellulose microfibril and matrix substance in wood cell wall induced by hygrothermal treatment, Wood Science, 52: 107-110.
-Albano, C., Ichazo, M., Gonzalez, J., Delgado, M., and Poleo, R., 2001. Effects of Filler Treatments on the Mechanical and Morphological Behavior of PP+Wood Flour and PP+Sisal Fiber. Journal of Material Research Innovation, 4: 284-293.
-Ates, S., Akyildiz, M. H., and Ozdemir, H., 2009. Effects of heat treatment on calabrian pine (pinus brutia Ten.) wood. Bioresources, 4(3): 1032-1043.
-Ding, T., Gu, L., and Liu, X., (2011). Influence of steam pressure on chemical changes of heat-treated Mongolian pine wood. Bioresources, 6(2):1880-1889.
-Doosthosseini, K., 2001. Wood composites materials; manufacturing, applications, Tehran University Press, 648p.
-Espert, A., Vilaplana, F., and Karlsson, S., 2004. Comparison of water absorption in natural cellulosic fiber from wood and one-year crops in polypropylene composites and its influence on their mechanical properties, Composites Part A.,  35: 1267-1276.
-Flex, J.M. and Gatenholm P., 1994. Effect of Transcrystalline Morphology on Interfacial Adhesion in Cellulose/Polypropylene Composites, Journal of Material Science, 29: 3043-3049.
-Folkes, M.J. and Hardwick, S.T., 1987. Direct Study of the Structure and Properties of Transcrystalline Layers, Journal of Material Science. 6: 656-658.
-Gray D.G., 1974. Polypropylene Transcrystallization at the Surface of Cellulose Fibers. Journal of Polymer Science: Polymer Letter Eddition, 12(9): 509-515.
-Hargitai, H., Rácz, I. and Anandjiwala, D., 2008. Development of Hemp Fiber Reinforced Polypropylene Composites. Journal of Thermoplastic Composite Materials, 21: 165-174.
-Jennings, J.D., 2003. Investigation the surface energy and bond performance of compression densified wood, M. Sc. Thesis, Virginia Polymeric Institute and State University, 147 p.
-Jiang, H., and Kamdem, D.P., 2004. Development of poly (vinyl chloride)/wood composites, A Literature Review, Journal of Vinyl and Additive Technology, 10: 59-69.
-Kaboorani, A., Faezipour, M., and Ebrahimi, G., 2008. Feasibility of using heat treated wood in woodplastic composites, Journal of Reinforced Plastics and Composites, 27: 1689-1699.
-Kocaefe, D., Poncsak, S., and Boluk, Y., 2008. Effect of thermal treatment on the chemical composition and mechanical properties of birch and aspen. Bioresources, 3(2): 517-537.
-Kord, B., 2011. Effect of Bark Flour Content on Mechanical Properties of Wood Plastic Composites, World Applied Sciences Journal, 14(3): 398-401.
-Kumar, A.P., Singh, R.P., and Sarwade, B.D., 2005.  Degradability of Composites, Prepared from Ethylene-Propylene Copolymer and Jute Fiber under Accelerated Aging and Biotic Environments, Materials Chemistry and physics., 92, 458-46.
-Mishra S., Naik J.B. and Patil Y.P., 2004. Studies on swelling properties of wood polymer composites based on agrowaste and novolac.  Journal of Advances in Polymer Technology, Vol 23, No 1, 46-50pp.
-Mohanty, A.K., Misra, M., and Drzal, L.T., 2005. Natural fibers, Biopolymers and Biocomposites, Taylor and Francis Group, Boca Raton, CRC Press 875p.
-Najafi, A., and Kazemi Najafi, S., 2007. Influence of Water Absorption on Mechanical Properties of Lignocellolusic /HDPE composites. In: Proceeding of 2th International Conference on Recent Advances in Composites Materials. Feb. 20-23 New Delhi, India, 213-218.
-Negro, M.J., Manzanares, P., Oliva J.M., Ballesteros I., and Ballesteros M., 2003. Changes in Various Physical/Chemical Parameters of Pinus Pinaster Wood after Steam Explosion Pretreatment, Biomass and Bioenergy, 25: 301-308.
-Pétrissans, M., Géradin, P., El-Bakali, I., and Seraj, M., 2003. Wettability of heat-treated wood. Journal of Applied Polymer Science, 69: 35-39.
-Robin, j.j., and Breton, Y., 2001. Reinforcement of recycled polyethylene with wood fiber heat treated. Journal of Reinforced Plastics and Composites, 20(14): 1235-1262.
-Saini, G., Narula, A.K., Choudhary, V., and Bhardwaj, J., 2009. Effect of particle size and alkali treatment of sugarcane bagasse on thermal, mechanical, and morphological properties of PVC-bagasse composites. Journal of Reinforced Plastics and Composites, 29(5): 731-740.
-Sanadi, A.R., Caulfield, D.F., and Jacobson, R.E., 1997. Agro-fiber thermoplastic composites: paper and composites from agro-based resources, Boca Raton, CRC Press: Lewis Publishers, 475p.
-Sanadi, A.R., and Caulfield, D.F., 2000. Transcrystalline Interfaces in Natural Fiber-PP Composites: Effect of Coupling Agent, Compos. Interface, 7: 31-43.
-Sewda, K., Maiti, S.N., 2007. Mechanical Properties of HDPE/Bark Flour Composites. Journal of Applied Polymer Science, 105: 2598-2604.
-Stark, N.M., Rowlands, R.E., 2003. Effects of wood fiber characteristics on mechanical properties of wood/polypropylene composites. Wood and Fiber Science, 35(2):167-174.
-Stokke, D.D., Gardner, D.J., 2003. Fundamental aspects of wood as a component of thermoplastic composites, J Vinyl Addit Technol, 9(2): 96-104.
-Tsoumis, G., 1991. Science and Technology of wood Structure textbook, Properties, Utilisation. Van Nostrand Reinhold, New York, 125p.
-Wang, W., and Morrell J.J., 2004. Water sorption characteristics of two wood-plastic composites, Forest Products Journal. 54: 209-212.
-Windeisen, E., Strobel, C., and Wegener, C., 2007. Chemical changes during the production of thermo treated beech wood. Wood Science and Technology, 41:523-536.
-Yang, H.S., Kim, H.J., Park, H.J., Lee, B.J., and Hwang, T.S., 2005. Water absorption behavior and mechanical properties of lignocellulosic filler polyolefin biocomposites, Journal of Composites Structures, (72): 429-437.
-Yildiz, S., and Gumuskaya, E., 2007. The effects of thermal modification on crystalline structure of cellulose in soft and hardwood. Building and Environment, 42: 62–67.