Copolymerization of ethylene with α-olefins over highly active supported Ziegler-Natta catalyst with vanadium active component

Document Type : Original research

Authors

1 China National Petroleum Corporation, Daqing Chemical Research Institute, Daqing 163714, Heilongjiang, China

2 Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Prospect Akademika Lavrentieva, 5, Novosibirsk 630090, Russia

3 Heilongjiang University, Harbine 150080, Heilongjiang, China

Abstract

The new highly active supported vanadium-magnesium catalyst (VMC) has been studied in α-olefin (1-butene, 1-hexene)/ ethylene copolymerization in the presence of hydrogen. Data on the effect of α-olefin/ethylene ratio in copolymerization on the content of branchings in copolymers, kinetic profile, copolymer yield, molecular weight and molecular weight distribution of copolymers have been obtained. It was found that both α-olefins are effective chain transfer agents in the ethylene-α-olefins copolymerization. The copolymerization ability of VMC is much higher than that of the well known titanium-magnesium catalysts. It was found that the use of optimal conditions of ethylene/α-olefin polymerization on the VMC catalyst makes it possible to obtain copolymers with a high yield (10-16 kg gcat-1 cat for 2 h) the copolymers having broad and bimodal MWD. Data on the branchings distribution in copolymers prepared with VMC catalyst have been obtained via fractionation of copolymers on the fractions with narrow polydispersity (Mw/Mn ≈ 2). Quite a uniform distribution of branchings over fractions with different molecular weight was found in distinction to inhomogeneous distribution of branchings in copolymers produced over the well known supported titaniu-magnesium catalyst.

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Main Subjects


  1. Umberto Z, Giuliano C (1983) Control of molecular-weight distribution in polyolefins synthesized with Ziegler-Natta catalytic systems. Adv Polym Sci 51: 101-153
  2. Shan CLP, Soares JBP, Pendilis A (2002) Mechanical properties of ethylene/1-hexene copolymers with tailored short chain branching distributions. Polymer 43: 767-773
  3. Frank PA, Ludwing LB, Hans-Frieder E, Joachim B (2001) Bimodal polyethylene. Interplay of catalyst and process. Macromol Symp 163: 135- 143
  4. Matta A, Zeng Y, Taniiki T, Terano M (2012) Vanadium-modified Philips catalyst with high branching ability for ethylene polymerization. Macromol React Eng 6: 346-350
  5. Comito RJ, Wu Zh, Zhang G, Lawrence III J A, Korzyński MD, Kehl JA, Miller JT, Dinča M (2018) Stabilized vanadium catalyst for olefin polymerization by site isolation in a metal-organic framework. Angew Chem Int Ed 57: 8135-8139
  6. Lorber C (2009) [ONNO]-type amine bis(phenolate)-based vanadium catalyst for ethylene homo- and copolymerization. Pure Appl Chem 81: 1205-1215
  7. Mikenas TB, Zakharov VA (1984) Polymerization of ethylene in the presence of the supported catalysts containing chloride of vanadium and chloride of magnesium. Vysokomol Soedin Ser B (in Russian) 26: 483-485
  8. Karol FG, Cann KJ, Wagner BE (1988) Development with high-activity titanium, vanadium and chromium catalyst in ethylene polymerization, in Transition Metals and Organometallics as Catalysts for Olefin Polymerization, ed. W. Kaminsky and H. Sinn, Springer-Verlag, Berlin
  9. Spitz R, Patin M, Robert P, Masson P, Dupuy J (1994) The control of molecule weight distribution in Ziegler–Natta catalysis, in Catalyst Design for Tailor-made Polyolefins, Kanazawa, Japan
  10. Zakharov VA, Echevskaya LG (1997) Kinetics of the copolymerization of ethylene with α- olefins initiated by supported titanium-magnesium and vanadium-magnesium catalyst. Polym Sci B (Engl. Transl.) 39: 291-294
  11. Mikenas TB, Zakharov VA, Echevskaya LG, Matsko MA (2001) Ethylene polymerization with supported vanadium-magnesium catalyst: hydrogen effect. Macromol Chem Phys 202: 475-481
  12. Zakharov VA, Makhtarulin SI, Sergeev S A, Mikenas T B, Nikitin V E, Echevskaya L G, Khmelinskaya AD (1995) Method of producing a deposited catalyst for the polymerization of ethylene and copolymerization of ethylene with α-olefins, WO Patent, WO 1995/03516
  13.  Zakharov VA, Echevskaya LG, Mikenas TB (1991) Studying of reaction of transfer of a polymeric chain with hydrogen at polymerization of ethylene over titanium-magnesium and vanadium-magnesium catalysts. Vysokomol Soedin Ser B (in Russian) 33: 102-104
  14. Czaja K, Bialek M (2001) Effect of hydrogen on the ethylene polymerization process over Ziegler– Natta catalysts supported on MgCl2(THF)2. II. Studies of the chain-transfer reaction. J Appl Polym Sci 79: 356-360
  15. Matsko MA, Bukatov GD, Mikenas TB, Zakharov VA (2001) Ethylene polymerization with supported vanadium-magnesium catalyst: Number of active centers and propagation rate constant. Macromol Chem Phys 202: 475-481
  16. Echevskaya LG, Matsko MA, Mikenas T B, Zakharov VA (2006) Molecular mass characteristics of polyethylene produced with supported vanadium-magnesium catalysts. Polymer Int 55: 165-170
  17. Wang D, Zhao Z, Mikenas TB, Xiaomei Lang, Echevskaya LG, Zhao C, Matsko M A, Wu W (2012) A new high-performance Ziegler– Natta catalyst with vanadium active component supported on highly-dispersed MgCl2 for producing polyethylene with broad/bimodal molecular weight distribution. Polym Chem 3: 2377-2382
  18. Echevskaya LG, Zakharov V A, Golovin AV, Mikenas TB (1999) Molecular structure of polyethylene produced with supported vanadium-magnesium catalyst. Macromol Chem Phys 200: 1434-1438
  19. Randall JC (1977) Polymer Sequence determination. Academic, New York
  20. Seppala JV, Koivumaki J (1993) Observations on the rate enhancement effect with magnesium chloride/titanium tetrachloride and dicyclopentadienylzirconium dichloride (Cp2ZrCl2) catalyst systems upon 1-hexene addition Macromolecules 26: 5535-5538
  21.  Cruz VL, Munoz-Escalone A, Martinez-Salazar J (1998) A theoretical study of the comonomer effect in the ethylene polymerization with zirconocene catalytic systems. J Polym Sci A Polym Chem 36: 1157-1167
  22. Jungling S, Koltzenburg S, Multhaupt R (1997) Propene homo- and copolymerization using homogeneous and supported metallocene catalysts based on Me2Si(2-Me-Benz[e] lnd)2ZrCl2. J Polym Sci Pol Chem 35: 1-8
  23. Awudza JAM, Tait P J T (2008) The “comonomer effect” in ethylene/α-olefin copolymerization using homogeneous and silica-supported Cp2ZrCl2/MAO catalyst systems: Some insights from the kinetics of polymerization, active center studies, and polymerization temperature. J Polym Sci. Pol Chem 46: 267-277
  24. Kravchenko R, Waymouth RM (1998) Ethylene− propylene copolymerization with 2-arylindene zirconocenes. Macromolecules 31: 1-6
  25. Tang L-M, Li Y-G, Ye W-P, Li Y-S (2006) Ethylene–propylene copolymerization with bis (β-enaminoketonato) titanium complexes activated with modified methylaluminoxane. J Polym Sci Pol Chem 44: 5846-5854
  26. Tang L-M, Hu T, Li P, Li Y-S (2005) Ethylene/ α-olefin copolymerization with bis(β- enaminoketonato) titanium complexes activated with modified methylaluminoxane. J Polym Sci Pol Chem 43: 6323-6330
  27. Gibson VC, Spitzmesser SK (2003) Advances in non-metallocene olefin polymerization catalysis. Chem Rev 103: 283-316
  28. Coates GW, Hustad PD, Reinartz S (2002) Catalysts for the living insertion polymerization of alkenes: access to new polyolefin architectures using Ziegler–Natta chemistry. Angew Chem Int Ed 41: 2236-2257
  29. Zakharov VA, Echevskaya LG, Mikenas TB, Matsko MA, Tregubov AA, Vanina MP, Nikolaeva MI (2008) Supported Ziegler-Natta catalysts for ethylene slurry polymerization and control of molecular weight distribution of polyethylene. Chinese J Polym Sci 26: 553-560
  30. Matsko МA, Echevskaya LG, Zakharov VA, Nikolaeva MI, Mikenas TB, Vanina MP (2009) Study of multi-site nature of supported Ziegler-Natta catalysts in ethylene-hexene-1 copolymerization. Macromol Symp 282: 157- 166
  31.  Garoff T, Mannonen L, Vaananen M, Eriksson V, Kallio K, Waldvogel P (2010) Chemical composition distribution study in ethylene/1- hexene copolymerization to produce LLDPE material using MgCl2-TiCl4-based Ziegler-Natta catalysts. J Appl Polym Sci 115: 826-836
  32. Nikolaeva MI, Matsko MA, Mikenas TB, Echevskaya LG, Zakharov VA (2012) Copolymerization of ethylene with α-olefins over supported titanium–magnesium catalysts. I. Effect of polymerization duration on comonomer content and the molecular weight distribution of copolymers. J Appl Polym Sci 125: 2034-2041
  33. Nikolaeva MI, Matsko MA, Mikenas TB, Echevskaya LG, Zakharov VA (2012) Copolymerization of ethylene with α-olefins over supported titanium–magnesium catalysts. II. Comonomer as a chain transfer agent. J Appl Polym Sci 125, 2042-2049
  34. Echevskaya LG, Zakharov VA (1996) Microtacticity of copolymers. Vysokomol Soedin Ser A 38: 959-963
  35. Matsko MA, Echevskaya LG, Vanina MP, Nikolaeva MI, Mikenas TB, Zakharov VA (2012) Study of the compositional heterogeneity of ethylene/1–hexene copolymers produced over supported catalysts of different composition. J Appl Polym Sci 126: 2017-2023
  • Receive Date: 11 November 2018
  • Revise Date: 11 December 2018
  • Accept Date: 17 December 2018
  • First Publish Date: 01 June 2019