Effect of Impact Modifier Type on Water Absorption and Thickness Swelling Parameters of Wood Flour- Recycled Polypropylene Composites

Document Type : Research Paper

Authors

Abstract

In this research, the effect of impact modifier type on water diffusion coefficient, maximum water absorption and thickness swelling parameters of wood flour- recycled polypropylene composites were evaluated. For this purpose, a virgin PP was thermo-mechanically degraded by two times extrusion under controlled conditions in a twin-screw extruder at a rotor speed of 100 rpm and a temperature of 1900C. The virgin and recycled PP in 2nd stage, compatibilizer (0, 2 % w/w) and wood flour were compounded at 50% weight sawdust loading in a counter-rotating twin-screw extruder in presence different type of impact modifiers (0, 6 % w/w). Ethylene vinyl acetate (EVA), ethylene-propylene-diene monomer (EPDM) and acrylonitrile-butadiene-styrene (ABS) were used as impact modifiers. The analysis of diffusion mechanism and thickness swelling rate were done based on Fick’s theory and swelling model for wood flour- recycled polypropylene composites. The composites containing two times recycled PP exhibited lower moisture diffusion coefficients, swelling rate parameter, maximum water absorption, thickness swelling. Also results showed that moisture diffusion coefficients and thickness swelling parameters of composites containing EVA are lower than composites containing EPDM and ABS. The use of compatibilizer decreased the moisture diffusion coefficients and thickness swelling parameters of the wood flour- recycled polypropylene composites
 

Keywords

References

1- Dick J. S. 1987. Compounding Materials for the Polymer Industries, Noyes Publications, New Jersey, USA, 288 p. (in Persian)
2- Adhikary, K. B., Pang, Sh., Staiger, M. P., 2008. Dimensional stability and mechanical behavior of wood–plastic composites based on recycled and virgin high-density polyethylene (HDPE), Composites: Part: B, (39), 807–815.
3- Bledzki, A. K., Faruk, O., 2003. Wood fibre reinforced polypropylene composites: effect of fibre geometry and coupling agent on physico-mechanical properties,Applied Composite Materials, (10): 365–379.
4- Espert, A, Vilaplana F, Karlsson S,. 2004. Comparison of water absorption in natural cellulosic fibres from wood and one-year crops in polypropylene composites and its influence on their mechanical properties, Composites: Part A (35), 1267–1276.
5- Hristov V. N., VasilevaS. T., 2004. Deformation mechanisms and mechanical properties of modified polypropylene/wood fiber composites, Polymer composite, (25) 5: 521-526.
6- Jafari S.H., Gupta A., 2000. Impact strength and dynamic mechanical properties correlation in elastomer-modified polypropylene, Applied Polymer Science Journal, (78): 962-971.
7- Kazemi Najafi, S., Hamidinia E. and Tajvidi M., 2006. Mechanical properties of composites from sawdust and recycled plastics, Journal of Applied Polymer Science, (100), 3641–3645.
8- Kazemi Najafi, S., Hamidinia E. and Tajvidi M., 2007. Effect of temperature, plastic type and virginity on the water uptake of sawdust/plastic composites. Holz ALS Roh und Werkstoff. 65(5): 377-382.
9- Kazemi Najafi, S., Kiaeifar, A. Tajvidi, M., Hamidinia, E. 2008. Hygroscopic thickness swelling rate of composites from sawdust and recycled plastics, Wood Science and Technology, DOI 10.1007/s00226-007-0163-4, 42:161–168.
10- Kazemi Najafi S, Mostafazadeh-Marznaaki, M., Chaharmahali M and Tajvidi M., 2009. Effect of thermomehcanical degradation of polypropylene on mechanical properties of wood-polypropylene composites, Journal of Composite Material., (43), 2543-2554.
11- Maciel A., Del Real A., Garcia Garduňo M. V., Oliva E., Manero O., Castaňo V. M., 1996. Morphology and elastic properties of PP/EVA polymer blends, Polymer International, 41 (3): 227-236.
12- Oksman K., Clemons C., 1998. Mechanical properties and morphology of impact modified polypropylene-wood flour composites, Applied Polymer Science, (67):1503-1513.
13- Oksuz M., Eroglu M., 2005. Effect of the elastomer type on the microstructure and mechanical properties of polypropylene, Journal of Applied Polymer Science, (98), 1445–1450.
14- Shakeri, A., Hoseini, S.K. and Ebrahimi Gh., 2005. Improvement in mechanical properties of cellulose fibers- thermoplastic polymer composites, Iranian Polymer Journal, ISSN 5523-6101, 143-150, (in Persian)
15- Tjong S.C., Xu S.A., Mai Y.W., 2003. Process-structure-property relationship in ternary short-glass-fiber/elastomer/polypropylene composites, Applied Polymer Science Journal, (88): 1384-1392.
16- Xu, Y. Wu, Q. Lei, Y. Yao, F. Zhang, Q., 2008, Natural fiber reinforced poly (vinyl chloride) composites: effect of fiber type and impact modifier, Journal of Polymer Environment, DOI 10.1007/s 10924-008-0113-8, 16: 250–257.
17- Yazdani H., Morshedian J., Khonakdar H.A., 2006. Effect of maleated polypropylene and impact modifiers on the morphology and mechanical properties of pp/mica composites, Polymer Composites Journal, DOI 10.1002/pc: 614-620.
18- Ghahri, S. 2010. Improvement of impact strength of wood flour- recycled polypropylene composites by using impact modifier, M. Sc. Thesis, Department of Wood and Paper Science and Technology, Tarbiat Modares University, 69 pages. (In Persian)
 
Iranian Journal of Wood and Paper Industries
Volume 2, Issue 2 - Serial Number 2
January 2012
Pages 115-24

Files

Share

How to cite

Statistics