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Bimodal polypropylene through binary metallocene catalytic systems: comparison between hybrid and mixed heterogeneous catalysts

  • Beatriz Paredes
  • Rafael van Grieken
  • Alicia Carrero
  • Ester Lopez-Moya
Original Paper

Abstract

Polypropylene with wider or bimodal molecular weight distribution is required for numerous applications since low molecular weight chains improve processability and high molecular weight fraction is required to get good mechanical properties. There are several routes to achieve a bimodal resin but the use of a binary catalytic system seems to be the most attractive, particularly with metallocenes combination. From a previous work two metallocenes were selected because they lead to polypropylenes with average molecular weights that differ in one order of magnitude. Two types of binary systems have been investigated, hybrid catalysts (two metallocenes loaded on the same support) and physical mixtures (two independent supported metallocenes that are introduced to the reactor and start the polymerization together), using different ratios, i.e., 25–75, 50–50, 75–25, at three reaction temperatures, i.e., 30, 50 and 70 °C. Most of the binary catalytic systems lead to bimodal molecular weight distributions. Polypropylenes produced by mixed catalysts are greatly influenced by the most active catalyst, while in PP coming from hybrid catalysts, as there is a strong interaction between both metallocenes, each one contributes according to its presence in the hybrid catalyst. Therefore, properties of obtained bimodal polypropylenes are quite influenced by the ratio between both metallocenes.

Keywords

Metallocene catalysts (poly)propylene (PP) Molecular weight distribution Isotactic Multicomponent or binary catalysts 

Notes

Acknowledgments

Financial support from “Ministerio de Educación y Ciencia” (Spain, Project number: CTQ2008-04601) is kindly acknowledged.

References

  1. 1.
    Malpass DB, Band E (2012) Introduction to industrial polypropylene: properties, catalysts, processes. Wiley, Beverly, MACrossRefGoogle Scholar
  2. 2.
    Resconi L, Cavallo L, Fait A, Piemontesi F (2000) Selectivity in propene polymerization with metallocene catalysts. Chem Rev 100:1253–1345CrossRefGoogle Scholar
  3. 3.
    Severn JR, Chadwick JC (2008) Tailor made polymers: via immobilization of alpha-olefin polymerization catalysts. Wiley-VCH Verlag GmbH & Co, KGaA, WeinheimCrossRefGoogle Scholar
  4. 4.
    Mark HF (2004) Encyclopedia of polymer science and technology. Wiley-Interscience, New JerseyGoogle Scholar
  5. 5.
    Soga K, Terano M (1994) Catalyst design for tailor-made polyolefins. Elsevier Science, B. V. AmsterdamGoogle Scholar
  6. 6.
    Sugimoto M, Masubuchi Y, Taimoto J, Koyama K (2001) Melt rheology of polypropylene containing small amounts of high-molecular-weight chain. 2. Uniaxial and biaxial extensional flow. Macromolecules 34(17):6056–6063CrossRefGoogle Scholar
  7. 7.
    Rodriguez F, Cohen C, Ober CK, Archer L (2003) Principles of polymer systems. Taylor & Francis, LondonGoogle Scholar
  8. 8.
    Shanks RA, Li J, Yu L (2000) Polypropylene–polyethylene blend morphology controlled by time–temperature–miscibility. Polymer 41(6):2133–2139CrossRefGoogle Scholar
  9. 9.
    Schreck M, Winter A, Dolle V, Kondoch H, Antberg M, Rohrmann J (1998) Process for the preparation of a polypropylene molding composition. US5708090 AGoogle Scholar
  10. 10.
    Ahn TO, Hong SC, Kim JH, Lee DH (1998) Control of molecular weight distribution in propylene polymerization with Ziegler-Natta/metallocene catalyst mixtures. J Appl Polym Sci 67:2213–2222CrossRefGoogle Scholar
  11. 11.
    Abedi S, Hassanpour N (2006) Preparation of bimodal polypropylene in two-step polymerization. J Appl Polym Sci 101:1456–1462CrossRefGoogle Scholar
  12. 12.
    Marques MFV, Pombo CC, Silva RA, Conte A (2003) Binary metallocene supported catalyst for propylene polymerization. Eur Polym J 39:561–567CrossRefGoogle Scholar
  13. 13.
    Marques MFV, Chaves EG (2003) Propylene fractions produced by binary metallocene catalysts. J Polym Sci, Part A: Polym Chem 41:1478–1485CrossRefGoogle Scholar
  14. 14.
    Bastos QC, Marques MFV (2005) Polypropylene reactor mixture obtained with homogeneous and supported catalysts. J Polym Sci, Part A: Polym Chem 43:263–272CrossRefGoogle Scholar
  15. 15.
    Tynys A, Eilertsen JL, Seppälä JV, Rytter E (2007) Propylene polymerizations with a binary metallocene system-chain shuttling caused by trimethylaluminium between active catalyst centers. J Polym Sci, Part A: Polym Chem 45:1364–1376CrossRefGoogle Scholar
  16. 16.
    Tynys A, Saarinen T, Bartke M, Lofgren B (2007) Propylene polymerization with novel heterogeneous combination metallocene catalyst systems. Polymer 48:1893–1902CrossRefGoogle Scholar
  17. 17.
    Ribeiro MR, Deffieux A, Portela MF (1997) Supported metallocene complexes for ethylene and propylene polymerizations; preparation and activity. Ind Eng Chem Res 36(4):1224–1237CrossRefGoogle Scholar
  18. 18.
    Kaminsky W, Winkelbach H (1999) Influence of supported metallocene catalysts on polymer tacticity. Top Catal 7(1–4):61–67CrossRefGoogle Scholar
  19. 19.
    Kittilsen P, McKenna TF, Svendsen H, Jakobsen HA, Fredriksen SB (2001) The interaction between mass transfer effects and morphology in heterogeneous olefin polymerization. Chem Eng Sci 56(13):4015–4028CrossRefGoogle Scholar
  20. 20.
    Severn JR, Chadwick JC, Duchateau R, Friederichs N (2005) “bound but not gagged”-immobilizing single-site α-olefin polymerization catalysts. Chem Rev 105:4073–4147CrossRefGoogle Scholar
  21. 21.
    Hlatky GG (2000) Single-site catalysts for olefin polymerization: annual review for 1997. Coord Chem Rev 199:235–329CrossRefGoogle Scholar
  22. 22.
    Fink G, Steinmetz B, Zechlin J, Przybyla C, Tesche B (2000) Propene polymerization with silica-supported metallocene/MAO catalysts. Chem Rev 100(4):1377–1390CrossRefGoogle Scholar
  23. 23.
    Kaminsky W, Renner F (1993) High melting polypropenes by silica-supported zirconocene catalysts. Macromol Rapid Commun 14(4):239–243CrossRefGoogle Scholar
  24. 24.
    van Grieken R, Carrero A, Suarez I, Paredes B (2007) Ethylene polymerization over supported MAO/(nBuCp)2ZrCl2 catalysts: influence of support properties. Eur Polym J 43(4):1267–1277CrossRefGoogle Scholar
  25. 25.
    dos Santos JHZ, Krug C, Barbosa da Rosa M, Stedile FC, Dupont J, Forte MDC (1999) The effect of silica dehydroxylation temperature on the activity of SiO2-supported zirconocene catalysts. J Mol Catal A Chem 139(2–3):199–207CrossRefGoogle Scholar
  26. 26.
    Simplicio LMT, Costa FG, Boaventura JS, Sales EA, Brandao ST (2004) Study of some parameters on zirconocene immobilization over silica. J Mol Catal A Chem 216(1):45–50CrossRefGoogle Scholar
  27. 27.
    Lopez-Moya E, Van Grieken R, Carrero A, Paredes B (2012) Bimodal polypropylene through binary metallocene catalytic systems as an alternative to melt blending. Macromol Symp 321-322:46–52CrossRefGoogle Scholar
  28. 28.
    González-Ruiz R, Quevedo-Sanchez B, Laurence R, Henson M (2006) Kinetic modeling of slurry propylene polymerization using rac-et(Ind)2ZrCl2/MAO. AICHE J 52(5):1824–1835CrossRefGoogle Scholar
  29. 29.
    Jungling S, Koltzenburg S, Mulhaupt R (1997) Propene homo- and copolymerization using homogeneous and supported metallocene catalysts based on Me2Si(me-Benz[e]Ind)2ZrCl2. J Polym Sci: Part A: Polym Chem 35(1):1–8CrossRefGoogle Scholar
  30. 30.
    Spaleck W, Antberg M, Rohrmann J, Winter A, Bachmann B, Kiprof P, Bahn J, Herrmann WA (1992) High molecular weight polypropylene through specifically designed zirconocene catalysts. Angew Chem Int Ed Eng 31(10):1347–1350CrossRefGoogle Scholar
  31. 31.
    Brintzinger HH, Fischer D, Mülhaupt R, Rieger B, Waymouth RM (1995) Stereospecific olefin polymerization with chiral metallocene catalysts. Angew Chem Int Ed Eng 34(11):1143–1170CrossRefGoogle Scholar
  32. 32.
    Quijada R, Guevara JL, Galland GB, Rabagliati FM, Lopez-Majada JM (2005) Synthesis and properties coming from the copolymerization of propene with α-olefins using different metallocene catalysts. Polymer 46(5):1567–1574CrossRefGoogle Scholar
  33. 33.
    Kaminsky W (1996) New polymers by metallocene catalysis. Macromol Chem Phys 197(12):3907–3945CrossRefGoogle Scholar
  34. 34.
    Xu JT, Feng LX (1999) Characterization of isotactic polypropylene prepared with dimethylsilyl bis(1-indenyl)zirconium dichloride supported on methylaluminoxane pretreated silica. Eur Polym J 35(7):1289–1294CrossRefGoogle Scholar
  35. 35.
    Meille SV, Ferro DR, Brückner S (1995) Recent results on the polymorphic behavior of isotactic polypropylene. Macromol Symp 89(1):499–511CrossRefGoogle Scholar
  36. 36.
    Lewin M, Pearce EM (1998) Handbook of fiber chemistry. Marcel Dekker Inc., New YorkGoogle Scholar
  37. 37.
    Hoyos M, Tiemblo P, Gómez-Elvira JM (2009) Influence of microstructure and semi-crystalline morphology on the β and γ mechanical relaxations of the metallocene isotactic polypropylene. Eur Polym J 45(4):1322–1327CrossRefGoogle Scholar
  38. 38.
    McCrum NG, Read BE, Williams G (1967) Anelastic and dielectric effects in polymeric solids. Wiley, New YorkGoogle Scholar
  39. 39.
    Bartenev GM, Aliguliev RM (1984) Relaxation transitions in polypropylene. Polym Sci USSR 26(6):1383–1394CrossRefGoogle Scholar
  40. 40.
    Arranz-Andrés J, Peña B, Benavente R, Perez E, Cerrada ML (2007) Influence of isotacticity and molecular weight on the properties of metallocenic isotactic polypropylene. Eur Polym J 43(6):2357–2370CrossRefGoogle Scholar
  41. 41.
    Brückner S, Phillips PJ, Mezghani K, Meille SV (1997) On the crystallization of γ-isotactic polypropylene: a high pressure study. Macromol Rapid Commun 18(1):1–7CrossRefGoogle Scholar
  42. 42.
    Alamo RG, Brown GM, Mandelkern L, Lehtinen A, Paukkeri R (1999) A morphological study of a highly structurally regular isotactic poly(propylene) fraction. Polymer 40(14):3933–3944CrossRefGoogle Scholar
  43. 43.
    Seock CH, Suck CY, Young L (2000) Control of molecular weight distribution for polyethylene catalyzed over Ziegler–Natta/Metallocene hybrid and mixed catalysts. J Mol Catal A Chem 159(2):203–213CrossRefGoogle Scholar
  44. 44.
    Takeshita H, S-i T, Arimoto M, Miya M, Takenaka K, Shiomi T (2009) Phase behavior and structure formation for diblock copolymers composed of side-chain liquid crystalline and glassy amorphous components. Polymer 50(1):271–278CrossRefGoogle Scholar
  45. 45.
    Skinner JL, Wolynes PG (1980) Solitons, defect diffusion, and dielectric-relaxation of polymers. J Chem Phys 73(8):4022–4025CrossRefGoogle Scholar
  46. 46.
    Wada Y, Hotta Y, Suzuki R (1968) Glass transition and relaxation in amorphous phase of isotactic polypropylene. J Polym Sci Part C: Polym Symp 23(2):583–595CrossRefGoogle Scholar
  47. 47.
    Palza H, Lopez-Majada JM, Quijada R, Benavente R, Pérez E, Cerrada ML (2005) Metallocenic copolymers of isotactic propylene and 1-octadecene: crystalline structure andmechanical behavior. Macromol Chem Phys 206(12):1221–1230CrossRefGoogle Scholar
  48. 48.
    Lopez-Majada JM, Palza H, Guevara JL, Quijada R, Martínez MC, Benavente R, Pereña JM, Perez E, Cerrada ML (2006) Metallocene copolymers of propene and 1-hexene: the influence of the comonomercontent and thermal history on the structure and mechanical properties. J Polym Sci B Polym Phys 44(8):1253–1267CrossRefGoogle Scholar
  49. 49.
    Nielsen LE, Landel RF (1994) Mechanical properties of polymers and composites. Marcel Dekker, Inc., New YorkGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  • Beatriz Paredes
    • 1
  • Rafael van Grieken
    • 1
  • Alicia Carrero
    • 2
  • Ester Lopez-Moya
    • 1
  1. 1.Department of Chemical and Environmental Technology, ESCETUniversidad Rey Juan CarlosMadridSpain
  2. 2.Department of Chemical and Energy Technology, ESCETUniversidad Rey Juan CarlosMadridSpain

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