Dinamik olarak vulkanize edilmiş PP/SR harmanlarının mekanik, ısıl ve morfolojik özelliklerinin incelenmesi

Yıl 2018, Cilt: 9 Sayı: 1, 325 - 335, 04.04.2018

Mehmet Kodal

Öz

Günümüzde termoplastikler gibi işlenebilmeleri nedeniyle termoplastik bir faz ve dinamik olarak çapraz bağlanmış bir elastomerden oluşan termoplastik vulkanizatlar (TPV) teknik ve ekonomik açıdan oldukça önem kazanmıştır. Bu çalışmada, endüstriyel olarak üretilen TPV’lere muadil olabilecek polipropilen (PP)/silikon kauçuk (SR) TPV’leri üretilmiş ve mekanik, ısıl ve morfolojik özellikleri incelenmiştir. PP matrisinde SR’yi çapraz bağlayabilmek için peroksit kürlenme ajanı ve çapraz bağlanma verimini artırmak içinse triallil izosiyanürat (TAIC) koajan olarak kullanılmıştır. Eriyik harmanlama sırasında yapılan tork ölçümleri, peroksit varlığında polipropilen/silikon kauçuk harmanlarının daha düşük eriyik viskozitesi değerleri sergilediğini göstermiştir. Peroksit ilavesi ile birlikte PP fazda meydana gelen zincir bölünme reaksiyonlarının PP/SR TPV’lerinin mekanik özelliklerini olumsuz yönde etkilediği, aksine TAIC ilavesiyle peroksit varlığında düşen mekanik özelliklerin kayda değer derecede arttığı tespit edilmiştir. Taramalı elektron mikroskopu (SEM) analizlerinden, SR’nin PP matrisinde homojen bir dağılım sergilediği gözlenmiştir. Diferansiyel taramalı kalorimetri (DSC) analiz sonuçlarından, SR ilavesinin PP’nin kristallenmesini baskıladığı tespit edilmiştir.

Anahtar Kelimeler

Polipropilen, Silikon kauçuk, Dinamik vulkanizasyon

Kaynakça

• Abadchi, M.R. ve Jalali-Arani, A., (2015). Synergistic effects of nano‑scale polybutadiene rubber powder (PBRP) and nanoclay on the structure, dynamic mechanical and thermal properties of polypropylene (PP), Iran Polymer Journal, 24, 805-813.
• Baldwin, F.P., Borzel, P., Cohen, C.A., Makowski, H.S. ve Van de Castle, J.F., (1970). The influence of residual olefin structure on EPDM vulcanization, Rubber Chemistry and Technology, 43, 522–548.
• Bartczak, Z., Galeski, A. ve Martuscelli, E. (1984). Spherulite growth in isotactic polypropylene-based blends: energy and morphological considerations, Polymer Engineering and Science, 24, 1155-1165.
• Chatterjee, K. ve Naskar, K., (2007). Development of thermoplastic elastomer based on maleated ethylene propylene rubber (m-EPM) and polypropylene (PP) by dynamic vulcanization, eXPRESS Polymer Letters, 1, 527-534.
• Coran, A.Y. ve Patel R., (1981). Rubber-thermoplastics compositions. Part IV. Thermoplastics vulcanizates from various rubber-plastic combinations, Rubber Chemistry and Technology, 54, 892-903.
• Demir, M.M., Menceloglu, Y.Z. ve Erman, B., (2005). Effect of filler amount on thermoelastic properties of poly(dimethylsiloxane) networks, Polymer, 46, 4127-4134.
• Florry, P.J. (1953). Principles of polymer chemistry, New York: Cornell University Press.
• George, S., Varughese, K.T. ve Thomas, S., (2000). Thermal and crystallization behavior of isotactic polypropylene/nitrile rubber blends, Polymer, 41, 5485-5503.
• Halimatuddahliana, Ismail, H. ve Md. Akil, H., (2005). The Effects of Dynamic Vulcanization by Dicumyl Peroxide (DCP) and N,N-m-phenylene bismaleimide (HVA-2) on the properties of polypropylene (PP)/ethylene-propylene diene terpolymer (EPDM)/natural rubber (NR) blends, Polymer-Plastics Technology and Engineering, 44, 1217-1234.
• Han, P.K. ve White J.L., (1995). Rheological studies of dynamically vulcanized and mechanical blends of polypropylene and ethylene-propylene rubber, Rubber Chemistry and Technology, 68, 728-738.
• Henning, S.K. ve Boye, W.M., (2009). Fundamentals of curing elastomers with peroxides and coagents II: understanding the relationship between coagent and elastomer, Rubber World, 240, 31-39.
• Hofmann, W., (1987). Crosslinking agents in ethylene-propylene rubbers. Kautschuk Gummi Kunststoffe, 40, 308–332.
• Khalili, S.M.R., Farsani, R.E. ve Rafiezadeh, S., (2011). An experimental study on the behavior of PP/EPDM/JUTE composites in impact, tensile and bending loadings, Journal of Reinforced Plastics and Composites, 30, 1341-1347.
• Kodal, M., (2016). Polypropylene/polyamide 6/POSS ternary nanocomposites: effects of POSS nanoparticles on the compatibility, Polymer, 105, 43-50
• Leite, P.R.S., Soares, B.G. ve Sirqueira, A.S., (2011). Dynamically vulcanized polypropylene/styrene-butadiene rubber blends: the effects of a peroxide/bismaleimide curing systems and composition, Journal of Applied Polymer Science, 120, 981-990.
• Martuscelli, E., Silvestre, C. ve Abate, G., (1982). Morphology, crystallization and melting behavior of films of isotactic polypropylene blended with ethylene-propylene, Polymer, 23, 229-237.
• Mohamad, N., Zainol, N.S., Rahim, F.F., Ab Maulod, H.E., Abd Rahim, T., Shamsuri, S.R., Asyadi, M., Abid, A.M.,Yaakub, M.Y., Abdollah, M.F. ve Abd Manaf, M.E. (2013). Mechanical and morphological properties of polypropylene/epoxidized natural rubber blends at various mixing ratio, Procedia Engineering, The Malaysian International Tribology Conference, Kuala Lumpur.
• Naskar, K., (2004). Dynamically vulcanized PP/EPDM thermoplastic elastomers: exploring novel routes for crosslinking with peroxides, Doktora tezi, University of Twente, The Netherlands.
• Patermann, S. ve Altstadt, V., (1998). PP/EPDM blends by dynamic vulcanization: influence of increasing peroxide concentration on mechanical, morphological and rheological characteristics, Proceedings of PPS-29, The 29th Annual Meeting of Polymer Processing Society 516-519, Nuremberg.
• Prut, E.V., Erina, N.A., Karger-Kocsis, J. ve Medintseva, T.I., (2008). Effets of blend composition and dynamic vulcanization on the morphology and dynamic viscoelastic properties of PP/EPDM blends, Journal of Applied Polymer Science, 109, 1212-1220.
• Sirin, H., Kodal, M., Karaagac, B. ve Ozkoc G., (2016). Effects of octamaleamic acid-POSS used as the adhesion enhancer on the properties of silicone rubber/silica nanocomposites, Composites Part B: Engineering, 98, 370-381.
• Soares, B.G., Santos, D.M. ve Sirqueira, A.S., (2008). A novel thermoplastic elastomer based on dynamically vulcanized polypropylene/acrylic rubber blends, eXPRESS Polymer Letters, 2, 602-613.
• Srinivasan, K.R. ve Gupta, A.K., (1994). Mechanical properties and morphology of PP/SEBS/PC blends, Journal of Applied Polymer Science, 53, 1-17.
• Thitithammawong, A., Nakason, C., Sahakaro, K. ve Noordermeer, J.W.M., (2007). NR/PP thermoplastic vulcanizates: selection of optimal peroxide type and concentration in relation to mixing conditions, Journal of Applied Polymer Science, 106, 2204-2209.
• Thitithammawong, A., Uthaipan, N. ve Rungvichaniwat, A., (2012). The effect of the ratios of sulfur to peroxide in mixed vulcanization systems on the properties of dynamic vulcanized natural rubber and polypropylene blends, Songklanakarin Journal of Science and Technology, 34, 653-662.
• Yilgor, E., Eynur, T., Kosak, C., Bilgin, S., Yilgor, I., Malay, O., Menceloglu, Y. ve Wilkes, G.L., (2011). Fumed silica filled poly(dimethylsiloxane-urea) segmented copolymers: preparation and properties, Polymer, 52, 4189-98.
• Zhang, X., Huang, H. ve Zhang, Y., (2002). Dynamically vulcanized nitrile rubber/polypropylene thermoplastic elastomers, Journal of Applied Polymer Science, 85, 2862-2866.