Browse > Article
http://dx.doi.org/10.14478/ace.2018.1052

Preparation of (n-BuCp)2ZrCl2 Catalyst Supported on SiO2/MgCl2 Binary Support and its Ethylene-1-hexene Copolymerization  

Carino, Ann Charise (Department of Chemical Engineering, Kongju National University)
Park, Sang Jun (Department of Chemical Engineering, Kongju National University)
Ko, Young Soo (Department of Chemical Engineering, Kongju National University)
Publication Information
Applied Chemistry for Engineering / v.29, no.4, 2018 , pp. 461-467 More about this Journal
Abstract
In this study, $(n-BuCp)_2ZrCl_2$, was supported on $SiO_2/MgCl_2$ binary support. Before supporting the catalyst, the $SiO_2/MgCl_2$ binary support was surface treated with three different alkyl aluminum compound, namely trimethylaluminum, triethylaluminum, and ethylaluminum sesquichloride. The synthesized surface-treated $SiO_2/MgCl_2$ supported metallocene catalysts were used for the copolymerization of ethylene and 1-hexene. Their catalytic properties and performances were analyzed through BET, XPS analysis, ICP-AES analysis, and FE-SEM. While the resulting copolymers were analyzed through DSC analysis, GPC analysis, 13C-NMR analysis, and FE-SEM. The analysis of synthesized surface-treated $SiO_2/MgCl_2$ supported metallocene catalysts showed that the Zr content of these catalysts is relatively lower compared to that of the catalyst supported on $SiO_2$. This could be attributed to the reduction in the surface area of $SiO_2$ due to the presence of recrystallized $MgCl_2$ and alkyl aluminum. Furthermore, they exhibited a better copolymerization activity compared to that of $SiO_2$ supported catalyst, particularly the EASC-surface treated binary support, which has the highest activity of 1.9 kg PE/($mmol-Zr^*hr$) because EASC acts as a strong Lewis acid. It could also be observed that the larger the ligand of alkyl aluminum used, the rougher the particle surface of the resulting polymer.
Keywords
metallocene catalyst; $SiO_2/MgCl_2$ binary support; alkyl aluminum; ethylene copolymerization;
Citations & Related Records
연도 인용수 순위
  • Reference
1 D.-H. Lee and K.-K. Yoon, Polymerization of ethylene by using zirconocene catalyst anchored on silica with trisiloxane and pentamethylene spacers, Macromol. Rapid Commun., 18, 427-431 (1997).   DOI
2 B. Monrabal, J. Blanco, J. Nieto, and J. B. P. Soares, Characterization of homogeneous ethylene/1-octene copolymers made with a single-site catalyst, CRYSTAF analysis and calibration, J. Polym. Sci. Polym. Chem., 37, 89-93 (1999).   DOI
3 W. Kaminsky, A. Bark, and R. Steiger, Stereospecific polymerization by metallocene/aluminoxane catalysts, J. Mol. Catal., 74, 109-119 (1992).   DOI
4 T. Yamasaki, Structure and lewis acid sites in alumoxane compounds, Catal. Today, 23, 425-429 (1995).   DOI
5 S. Patthamasang, B. Jongsomjit, and P. Praserthdam, Effect of EtOH/$MgCl_2$ molar ratios on the catalytic properties of $MgCl_2-SiO_2/TiCl_4$ Ziegler-Natta catalyst for ethylene polymerization, Molecules, 16, 8332-8342 (2011).   DOI
6 S. Sensarma and S. Sivaram, Polymerization of ethylene using a $SiO_2-MgCl_2$ supported bis(cyclopentadienyl)zirconium (IV) or titanium (IV) dichloride catalyst, Polym. Int., 51, 417-423 (2002).   DOI
7 H. S. Cho, Y. H. Choi, and W. Y. Lee, Characteristics of ethylene polymerization over Ziegler-Natta/metallocene catalysts: Comparison between hybrid and mixed catalysts, Catal. Today, 63, 523-530 (2000).   DOI
8 Y. G. Ko, H. S. Cho, K. H. Choi, and W. Y. Lee, The characteristics of metallocene/Ziegler-Natta hybrid catalysts supported on the recrystallized $MgCl_2$, Korean J. Chem. Eng., 16, 562-570 (1999).   DOI
9 H. S. Cho and W. Y. Lee, Preparation of inorganic $MgCl_2$-alcohol adduct and its application in organometallic HYBRID catalysts for ethylene polymerization, Korean J. Chem. Eng., 19, 557-563 (2002).   DOI
10 S. Karakalos, A. Siokou, and S. Ladas, The interfacial properties of $MgCl_2$ films grown on a flat $SiO_2$/Si substrate, An XPS ans ISS study, Appl. Surf. Sci., 225, 8941-8946 (2009).
11 F. Garbassi and L. Pozzi, Electron beam effects on hydrated magnesium chloride revealed by XPS, J. Electron Spectrosc., 16, 199-203 (1979).   DOI
12 H.-X. Zhang, Y.-J. Lee, J.-R. Park, D.-H. Lee, and K.-B. Yoon, Control of molecular weight distribution for polypropylene obtained by a commercial Ziegler-Natta Catalyst: Effect of a cocatalyst and hydrogen, J. Appl. Polym. Sci., 120, 101-108 (2011).   DOI