The influence of the oxygen donor capacity of polystearylmethacrylate over polyethylene bulk density when using modified methylaluminoxane as co-catalyst

Document Type : Short Communication


Departamento de Química Macromolecular y Nanomateriales, Centro de Investigación en Química Aplicada, 25294, Saltillo, Coahuila, México


In this work, the interaction between a polystearylmethacrylate (Mn = 8,900 g mol-1, Xn = 26, Ð = 1.1) and modified methylaluminoxane 12 (MMAO-12) co-catalyst is studied using different spectroscopic methods. The effect of this oxygen-donor additive was measured by the changes in the bulk density of the raw polyethylene, which resulted increased respect to those obtained in blank reactions. A decrease in the activity was also observed as a penalty for the improvement of the bulk density, enhancing the possibility of reducing fouling. The coordination of the carbonyl oxygen groups of polystearylmethacrylate to aluminum (III) centers is confirmed by 1H-NMR and FTIR studies, and by a simple semi-empirical computational calculation. A method for obtaining a tri-component co-catalyst mixture is described using the methyl-bridging capacity of trimethylaluminum and its Lewis acidity to get the polystearylmethacrylate and MMAO-12 linked together. This robust adduct introduces a hierarchy over the PE chain growing, leading to higher bulk densities for PE beads (0.43 g cm-3) concerning blank reactions (0.26 g cm-3).


Main Subjects

  1. Kaminsky W (1994) Zirconocene catalysts for olefin polymerization. Catal Today 20: 257-270
  2. Kaminsky W, Duch A (1996) New developments in olefin polymerization with metallocene catalysts. Catalysts in petroleum refining and petrochemical industries, 1st , Elsevier, 91-98
  3. Kaminsky W (1998) Highly active metallocene catalysts for olefin polymerization. J Chem Soc Dalton 9: 1413-1418
  4. Lee BY, Chung YK, Lee SW (1999) Synthesis of bis(1,2,3-substituted cyclopentadienyl) zirconium dichloride derivatives and their use in ethylene polymerization. J Organomet Chem 587: 181–190
  5. Lee KS, Yim JH, Ihm SK (2000) Characteristics of zirconocene catalysts supported on Al- MCM-41 for ethylene polymerization. J Mol Catal A-Chem 159: 301-308
  6. Pothirat T, Jongsomjit B, Praserthdam P (2008) A comparative study of SiO2- and ZrO2-supported zirconocene/MAO catalysts on ethylene/1-olefin copolymerization. Catal Commun 9: 1426-1431
  7. Laine A, Linnolahti M, Pakkanen TA (2012) Alkylation and activation of metallocene polymerization catalysts by reactions with trimethylaluminum: A computational study. J Organomet Chem 716: 79-85
  8. Zijlstra HS, Joshi A, Linnolahti M, Collins S, Mcindoe JS (2018) Modifying methylalumoxane via alkyl exchange. Dalton Trans 47: 17291- 17298
  9. Zijlstra HS, Joshi A, Linnolahti M, Collins S, Mcindoe JS (2019) Interaction of neutral donors with methylaluminoxane. Eur J Inorg Chem 2019: 2346-2355
  10. Joshi A, Collins S, Linnolahti M, Zijlstra HS, Liles E, Mcindoe JS (2021) Spectroscopic studies of synthetic methylaluminoxane: Structure of methylaluminoxane activators. Chem-Eur J
  11. Linnolahti M, Collins S (2017) Formation, structure, and composition of methylaluminoxane. Chem Phys Chem 18: 3369-3374
  12. Belelli PG, Castellani NJ (2003) DFT studies of Zirconocene/MAO interaction. J Mol Catal A-Chem 192: 9-24
  13. Tymińska N, Zurek E (2015) DFT-D investigation of active and dormant methylaluminoxane (MAO) species grafted onto a magnesium dichloride cluster: A model study of supported mao. ACS Catal 5: 6989-6998
  14. Ustynyuk LY, Bulychev BM (2015) Activation effect of metal chlorides in post-metallocene catalytic systems for ethylene polymerization: A DFT study. J Organomet Chem 793: 160-170
  15. Ferreira ML, Damiani ED, Juan A (1998) Semiempirical study of metallocenes adsorption on β-MgCl2. Comput Mater Sci 9: 357-366
  16. Stewart JJ (2009) Application of the PM6 method to modeling proteins. J Molecul Model 15: 765- 805
  17. Estrada-Ramirez AN, Ventura-Hunter C, Vitz J, Díaz-Barriga E, Peralta-Rodriguez R, Schubert US, Guerrero-Sánchez C, Pérez-Camacho O (2019) Poly(n-alkyl methacrylate)s as metallocene catalyst supports in nonpolar media. Macromol Chem Phys 220: 1900259
  18. Imhoff DW, Simeral LS, Blevins DR, Beard WR (1999) Determination of trimethylaluminum and characterization of methylaluminoxanes using proton NMR. In: Olefin Polymerization. ACS symposium series 749: 177-191
  19. Belelli PG, Castellani NJ (2006) Counterion and additive effects on ethylene coordination and insertion in metallocene catalyst. J Mol Catal A-Chem 253: 52-61
  20. Blaakmeer ESM, van Eck ERH, Kentgens APM (2018) The coordinative state of aluminium alkyls in Ziegler-Natta catalysts. Phys Chem Chem Phys 20: 7974-7988
  21. Nakamoto K (2009) Infrared and Raman spectra of inorganic and coordination compounds. Part A: Theory and applications in inorganic chemistry, 6th ed., Wiley, 192-213
  22. Slaughter J, Peel AJ, Wheatley AE (2017) Reactions of trimethylaluminium: Modelling the chemical degradation of synthetic lubricants. Chemistry 23: 167-175
  23. Knuuttila H, Lehtinen A, Nummila-Pakarinen A (2004) Advanced Polyethylene Technologies- Controlled Material Properties. Adv Polym Sci 169, 13-28
  24. Malpass DB (2010) Introduction to Industrial Polyethylene Properties, Catalysts, and Processes, Wiley-VCH, Ch. 1: 52-55; 91-93
  25. Wang D, Yang G, Guo F, Wang J, Jiang Y (2018) Progress in technology and catalysts for continuous stirred tank reactor type slurry phase polyethylene processes. Petrol Chem 58: 264-273
  • Receive Date: 12 January 2022
  • Revise Date: 06 February 2022
  • Accept Date: 16 February 2022
  • First Publish Date: 16 February 2022