Document Type : Research Paper

Authors

School of Chemical, Petroleum and Gas Engineering, Iran Uinersity of Science and Technology, Tehran, Iran

Abstract

Polypropylene has a poor toughness and impact strength. So, it needs to modification for some applications. Addition of elastomers to PP to enhance the toughness is a traditional way, but it causes to decrease of the modulus and tensile strength of products. In this research a hybrid composite system including PP, thermoplastic elastomer, nanoparticle and compatibilizer was prepared by melt mixing method. The interaction effect of nanoparticle, thermoplastic elastomer, and compatibilizer on the tensile and impact properties of composites were studied using the experimental design technique; response surface methodology. The results of microscopy analysis showed that the blends were two-phase, where thermoplastic elastomer was dispersed phase. The elastomeric particle size was in the range of 100-400 nm and by increasing the rubber content, rubber particle size increased. Nanosilica dispersed in the presence of compatibilizer had a particle size between 40-90 nm, while the lack of compatibilizer created some agglomerations of nanoparticles. As elastomer content increased, the strain of failure and impact strength of nanocomposites increased, while the Young modulus and tensile strength were decreased. Addition of nanosilica to the PP in the absence of compatibilizer lowered the tensile and impact strengths. While, addition of nanosilica along with compatibilizer improved the tensile modulus of blends. According to the experimental design results, some mathematical relations were presented to predict the mechanical properties. The optimal hybrid nanocomposite had significantly higher impact strength than pure PP while their moduli were in the same order.

Keywords

Main Subjects

[1]     Fasihi, M. and Mansouri, H., "Effect of Rubber Interparticle Distance Distribution on Toughening Behavior of Thermoplastic Polyolefin Elastomer Toughened Polypropylene" Journal of Applied Polymer Science, Vol. 133, No. 40,  pp. 44068, 2016.
[2]     Abreu, F. Forte, M. and Liberman, S., "SBS and SEBS Block Copolymers as Impact Modifiers for Polypropylene Compounds" Journal of applied polymer science, Vol. 95, No. 2, pp. 254-263, 2005.
[3]     Panaitescu, D.M., "Morphological Investigation of PP/Nanosilica Composites Containing SEBS "Polymer Testing, Vol. 31, No. 2, pp. 355-365, 2012.
[4]     Ranjbar, M. Arefazar, A. Bakhshandeh, Gh., "Constituting Balance Between Strength and Toughness in Nanocomposites Based on PP/SEBS-G-MA Blends" Journal of Thermoplastic Composite Materials, Vol. 27, No. 12,  pp. 1589-1606, 2014.
[5]     Paul, S. and Kale, D., “Impact Modification of Polypropylene Copolymer with a Polyolefinic Elastomer” Journal of Applied Polymer Science, Vol. 76, No. 9, pp. 1480-1484, 2000.
[6]     Liu, G. and Qiu, G., “Study on the Mechanical and Morphological Properties of Toughened Polypropylene Blends For Automobile Bumpers” Polymer Bulletin, Vol. 70, No. 3, pp. 849-857, 2013.
[7]     Bajsić, EG. Šmit, I. and Leskovac, M., “Blends of Thermoplastic Polyurethane and Polypropylene. I. Mechanical and Phase Behavior” Journal of Applied Polymer Science, Vol. 104, No. 6, pp. 3980-3985, 2007.
[8]     Ajili, SH. Ebrahimi, NG. and Khorasani, MT., “Study on Thermoplastic Polyurethane/Polypropylene (TPU/PP) Blend as a Blood Bag Material” Journal of Applied Polymer Science, Vol. 89, No. 9,  pp. 2496-2501, 2003.
[9]     Liang, JZ., “Mechanical Properties and Morphology of Polypropylene/Poly (ethylene-co-octene) Blends” Journal of Polymers and the Environment,.Vol. 20, No. 3, pp. 872-878, 2012.
[10]  Lee, S. Kontopoulou, M. and Park, C., “Effect of Nanosilica on the Co-Continuous Morphology of Polypropylene/ Polyolefin Elastomer Blends” Polymer, Vol. 51, No. 5, pp. 1147-1155, 2010.
[11]  Rong, MZ., “Structure–Property Relationships of Irradiation Grafted Nano-Inorganic Particle Filled Polypropylene Composites” Polymer, Vol. 42, No. 1, pp. 167-183, 2001.
[12]  Liu, Y. and Kontopoulou, M., “The Structure and Physical Properties of Polypropylene and Thermoplastic Olefin Nanocomposites Containing Nanosilica” Polymer, Vol. 47, No. 22, pp. 7731-7739, 2006.
[13]  Chen, JH., “Interfacial Enhancement of Nano-Sio 2/Polypropylene Composites” Composites Science and Technology, Vol. 69, No.2,  pp. 252-259, 2009.
[14]  Zanjanijam, AR. Hakim, Sh. and Azizi, H., “Morphological, Dynamic Mechanical, Rheological and Impact Strength Properties of the PP/PVB Blends: The Effect of Waste PVB as a Toughener” RSC Advances, Vol. 6, pp. 44673-44686, 2016.
[15]  Bikiaris, DN., “Compatibilisation Effect of PP-g-MA Copolymer on Ipp/Sio2 Nanocomposites Prepared By Melt Mixing” European Polymer Journal, Vol. 41, No.9, pp. 1965-1978, 2005.
[16]  Langroudi, AE. and Akkaf, MH., “Improvement in the Mechanical Properties of Polyester Nanocomposite with Nano -Silica Prepared by Sol-Gel Method” Journal of Science and Technology of Composites, Vol. 3, No. 4, pp. 419-428, 2017. (In Persian)
[17]  Montgomery, DC.,  “Design and Analysis of Experiments” John Wiley & Sons, New York, 2008.
Banerjee, S., Joshi, M. and Ghosh, A.K., “Optimization of Polypropylene/Clay Nanocomposite Processing Using Box-Behnken Statistical Design” Journal of Applied Polymer Science, Vol. 123, No. 4,  pp. 2042-2051, 2012