Effects of Kenaf and Rice Husk on Water Absorption and Flexural Properties of Kenaf/CaCO3/HDPE and Rice Husk/CaCO3/HDPE Hybrid Composites
Rice husk and kenaf filled with calcium carbonate
(CaCO3) and high density polyethylene (HDPE) composite were
prepared separately using twin-screw extruder at 50rpm. Different
filler loading up to 30 parts of rice husk particulate and kenaf fiber
were mixed with the fixed 30% amount of CaCO3 mineral filler to
produce rice husk/CaCO3/HDPE and kenaf/CaCO3/HDPE hybrid
composites. In this study, the effects of natural fiber for both rice
husk and kenaf in CaCO3/HDPE composite on physical, mechanical
and morphology properties were investigated. Field Emission
Scanning Microscope (FeSEM) was used to investigate the impact
fracture surfaces of the hybrid composite. The property analyses
showed that water absorption increased with the presence of kenaf
and rice husk fillers. Natural fibers in composite significantly
influence water absorption properties due to natural characters of
fibers which contain cellulose, hemicellulose and lignin structures.
The result showed that 10% of additional natural fibers into hybrid
composite had caused decreased flexural strength, however additional
of high natural fiber (>10%) filler loading has proved to increase its
 C. F.-V. C. Gonzales-Sanches, A. Ochoa-Mendoza, A. Garriga-Meco, E. Rodriguez-Hurtado, "Rheological behavior of original and recycled cellulose-polyolefin composite materials," Composites : Part A, vol. 42, pp. 1075-1083, 2011.
 S. S. Alireza Ashori, "Hybrid composites made from recycled material: Moisture absorption and thickness swelling behavior " Bioresource Technology, vol. 101, pp. 4717-4720, 2010.
 R. M. Noor Zuhaira Abd Aziz, "Comparison of melt flow and mechanical properties of rise husk and kenaf hybrid composites," Advanced Materials Research, vol. 701, pp. 42-46, 2013.
 H. I. Xuan Viet Cao, Azura A. Rashid, Tsutomu Takeichi, Thao Vo-Huu, "Mechanical properties and water absorption of kenaf powder filled recycled high density polyethylene/natural rubber biocomposites using MAPE as a compatibilizer," BioResource, vol. 6, pp. 3260-3271, 2011.
 A. A. Amir Nourbakhsh, "Wood plastic composites from agro-waste materials: Analysis of mechanical properties," Bioresource Technology, vol. 101, pp. 2525-2528, 2010.
 H. I. Hattotuwa G.B. Premalal, A.Baharin "Comparison of the mechanical properties of rice husk powder filled polypropylene composites with talc filled polypropylene composites " Polymer Testing, vol. 21, pp. 833-839, 2002.
 H. J. K. Han Seung Yang, Jungil Son, Hee Jun Park, Bum Jae Lee, Taek Sung Hwang, "Rice husk flour filled polypropylene composites; mechanical and morphological study," Composites Structures, vol. 63, pp. 305-312, 2004.
 G. R. Liu, "A step by step method of rule of mixture fiber and particle composite materials," Composite Structures vol. 40, pp. 313-322, 1997.