2018 Vol.4 No.2:12 Research Article DOI: 10.4172/2471-9935.100040 iMedPub Journals www.imedpub.com 1 © Under License of Creative Commons Attribution 3.0 License | This article is available in: http://polymerscience.imedpub.com/archive.php Polymer Sciences ISSN 2471-9935 Kwang Su Seo 1 *, Susan A Lettieri 2 , Steve K Henning 2 , Weng-Liang Hsu 2 , Adel F Halasa 1 * 1 Insttute of Polymer Science, The University of Akron, Akron, OH, USA 2 The Goodyear Tire and Rubber Co., 142 Goodyear Blvd., Akron, OH, USA *Corresponding authors: Adel F. Halasa Kwang Su Seo  halasa@uakron.edu, mura1977@hotmail.com Insttute of Polymer Science, The University of Akron, Akron, OH, USA Tel: +82-10-2378-0381 Citaton: Seo KS, Leteri SA, Henning SK, Hsu WL, Halasa AF (2018) Determinaton of Reactvity Ratos for α-Methylstyrene- Butadiene Copolymerizaton via Cesium- based Catalyst System. Polym Sci Vol.4 No.2:12 Introducton The use of α-methylstyrene as a monomer has been limitedly applied to low temperature polymerizaton system due to the ceilingtemperatureofα-methylstyrene[1-4].Therestricton tolow temperatures results from the thermodynamic equilibrium that favors a dimer over higher oligomers as the ceiling temperature of a-methylstyrene is approached [6-11]. The copolymerizaton of α-methylstyrene and conjugated dienes in hydrocarbon solvent at 65-75°C was studied using a novel new catalyst system based on organometallic compound of group I (n-butyl lithium) or group II (dibutyl magnesium) in combinaton with the alkoxides potassium or cesium of 2-etylhexyl alcohol in the presence of chelatng diamine such as, N,N,N’,N’-tetramethylethylene diamine [TMEDA, 9]. The catalyst system based on the cesium alkoxide/TMEDA/ dibutyl magnesium in molar rato 2:2:1 has previously proven that a comonomer mixture of α-methylstyrene and butadiene can be copolymerized at 65°C without the homopolymerizaton of α-methylstyrene [9]. The monomer of α-methylstyrene should be incorporated into the polymer chain as singlet units with the possibility of a small fracton of diads, since the rate of self- propagaton for α-methylstyrene is near zero in high temperature [10,11], the rate of cross-propagaton must be higher. Therefore, α-methylstyrene can be fully converted into a polymer chain, restrictng the negatve rate efect of depropagaton. Determining the reactvity ratos for the copolymerizaton [12] of a-methylstyrene and 1,3-butadiene should provide further insight to the incorporaton order outlined above. Diferental methods and the integrated method of determining r 1 and r 2 based on the copolymer compositon equaton will be used to model the poly(α-methylstyrene-co-butadiene) rubber (α-MeSBR) copolymerizaton system. Experimental The anionic soluton polymerizaton of α-methylstyrene (α-MeS) and 1,3-butadiene (Bd) was polymerized from 15wt% monomer concentraton (315g monomer in 2100 total g hexane soluton) in one-gallon reactor equipped with air driven motor strrer nitrogen inlet and a cooling coil. Feed ratos of 10, 20, 30, 40, and 50 wt% α-MeS were used to polymerize the fve α-MeSBRs used in the study. The reactons were run at 10°C to slow the kinetcs enough to provide accurate conversion data. The catalyst consists of Cesium salt of 2-ethyl hexyl alcohol (6.3 mmol) reduced with Determinaton of Reactvity Ratos for α-Methylstyrene-Butadiene Copolymerizaton via Cesium-based Catalyst System Received: July 09, 2018; Accepted: July 31, 2018; Published: August 06, 2018 Abstract The objectve of this work is to determine reactvity ratos of the poly(α-methylstyrene-co- butadiene) polymerizaton in cesium-based catalyst system. These values can be used to describe the characteristc incorporaton order of the monomers into the polymer chain and model the chain microstructure. The anionic soluton polymerizaton of α-methylstyrene and 1,3-butadiene was polymerized at 10°C with diferent feed ratos in the presence of Cesium alkoxide, dialkyl magnesium, and chelatng diamine. The reactvity rato for butadiene at 50/50 wt% (35/65 molar rato) α-methylstyrene/butadiene calculated as approximately 1.50, while that for α-methylstyrene calculated by both the integrated and diferental methods were the values of 0.40 and -0.1. This would indicate that copolymer compositon equaton needs to be modifed to include propagaton-depropagaton equilibrium phenomenon. Keywords: Copolymerizaton; Coplolymer; Polymerizaton; α-methylstyrene; Catalyst system