Effect of Novel Ether and Conventional Silane External Donors on the 4th Generation of Ziegler-Natta Catalysts for Propylene Polymerization

Document Type : Research Article


1 Department of Chemistry, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran, I.R. IRAN

2 Polymer Department, AmirKabir University, Tehran, Iran

3 Iran Polymer and Petrochemical Institute (IPPI), P.O. Box: 14977-13115, Tehran, I.R. IRAN


In this research, five etheric compounds with different numbers of methoxy groups were synthesized by Williamson reaction. These ether compounds were characterized by 1HNMR, 13CNMR, and FTIR techniques and then were employed as external electron donors for the polymerization of propylene with Ziegler-Natta catalyst for comparison with cyclohexylmethyldimethoxysilane (C-Donor) and dicyclopentyldimethoxy silan (D-Donor). Polymerization of propylene was carried out using MgCl2-supported Ziegler–Natta catalyst (MgCl2/ID/TiCl4) containing a phthalate type internal electron donor in the presence of trimethylaluminum cocatalyst and hydrogen with external donors, to compare the influence of ether and silane compounds in properties of polypropylene. The role of these etheric compounds and industrial alkoxysilanes on the properties of polypropylene were studied by using O-xylene solubility method, Melt Flow Index (MFI) and Differential Scanning Calorimetry (DSC). The productivity, crystallinity, and isotacticity of the obtained polypropylene were influenced by external electron donors. Also, the morphology of the industrial Ziegler-Natta catalyst and polypropylenes produced using these catalysts in the presence of different external donors were determined by Scanning Electron Microscope (SEM).


Main Subjects

[1] Kissin Y., “Alkene Polymerization Reactions with Transition Metal Catalysts”, Elsevier Science, Amsterdam, Netherlands (2008).
[2] Bazhenov A., Linnolahti M., Pakkanen T. A., Denifl P., Leinonen T., Modeling the Stabilization of Surface Defects by Donors in Ziegler–Natta Catalyst Support, J. Phys. Chem. C., 118 (9): 4791-4796 (2014).
[3] Alshaiban A., Soares J. B., Effect of Hydrogen, Electron Donor, and Polymerization Temperature on Poly(propylene) Microstructure, Macromol. Symp., Wiley Online Library, 312: 72-80 (2012).
[4] Claverie J. P., Schaper F., Ziegler-Natta Catalysis: 50 Years After the Nobel Prize, MRS Bull., 38(03): 213-218 (2013).
[5] Gnanakumar E. S., Gowda R. R., Kunjir S., Ajithkumar T., Rajamohanan P., Chakraborty D., Gopinath C. S., MgCl2.6CH3OH: A Simple Molecular Adduct and Its Influence As a Porous Support for Olefin Polymerization, ACS Catal., 3(3): 303-311 (2013).
[6] Gnanakumar E. S., Thushara K., Bhange D. S., Mathew R., Ajithkumar T., Rajamohanan P., Bhaduri S., Gopinath C. S., MgCl2.6PhCH2OH - A New Molecular Adduct as Support Material for Ziegler–Natta Catalyst: Synthesis, Characterization and Catalytic Activity, Dalton Trans., 40(41): 10936-10944 (2011).
[7] Correa A., Credendino R., Pater J. T., Morini G., Cavallo L., Theoretical Investigation of Active Sites at the Corners of MgCl2 Crystallites in Supported Ziegler-Natta Catalysts, Macromol., 45(9): 3695-3701 (2012).
[8] Groppo E., Seenivasan K., Barzan C., The Potential of Spectroscopic Methods Applied to Heterogeneous Catalysts for Olefin Polymerization, Catal. Sci. Tech., 3(4): 858-878 (2013).
[10] Bazhenov A. S., Denifl P., Leinonen T., Pakkanen A., Linnolahti M., Pakkanen T. A., Modeling Coadsorption of Titanium Tetrachloride and Bidentate Electron Donors on Magnesium Dichloride Support Surfaces, J. Phys. Chem. C, 118(48): 27878-27883 (2014).
[11] Dil E. J., Pourmahdian S., Vatankhah M., Afshar-Taromi, F., Effect of Dealcoholation of Support in MgCl2-Supported Ziegler–Natta Catalysts on Catalyst Activity and Polypropylene Powder Morphology, Polym. Bull., 64 (5): 445-457 (2010).
[12] Chumachenko N.; Zakharov V.; Bukatov G.; Sergeev S., A Study of the Formation Process of Titanium-Magnesium Catalyst for Propylene Polymerization, Applied Catalysis A: General, 469: 512-516 (2014).
[14] Zakirov M., Kleiner V., Adrov O., Nifant’ev I., Shklyaruk B., Stroganov V., Nedorezova P., Klyamkina A., Effect of Electron Donors on Polymerization of Propylene in the Presence of Titanium-Magnesium Catalysts, Polym. Sci. Ser. B, 52(9-10): 584-588 (2010).
[15] Kim S. Y., Hiraoka Y., Taniike T., Terano M., In External Donor Induced Direct Contact Effects on Mg(OC2H5)2‐Based Ziegler‐Natta Catalysts for Propylene Polymerization, Macromol. Symp., Wiley Online Library, 285 (1): 115-120 (2009).
[16] Zhang H. -X., Lee Y. -J., Park J. -R., Lee D. -H., Yoon, K. -B., Control of Molecular Weight Distribution for Polypropylene Obtained by Commercial Ziegler-Natta Catalyst: Effect of Temperature, Polym. Bull., 67(8): 1519-1527 (2011).
[17] Alshaiban A., Soares J. B., Effect of Hydrogen and External Donor on Propylene Polymerization Kinetics with a 4th‐Generation Ziegler‐Natta Catalyst, Macromol. React. Eng., 6(6‐7): 265-274 (2012).
[18] Zhang H. -X., Lee Y. -J., Park J. -R., Lee D. -H., Yoon K. -B., Control of Molecular Weight Distribution for Polypropylene Obtained by Commercial Ziegler-Natta Catalyst: Effect of Electron Donor, Macromol. Res., 19(6): 622-628 (2011).
[19] Da Silva Filho A. A., Alves M., do Carmo M., dos Santos J. H. Z., XPS and EXAFS Characterization of Ziegler-Natta Catalyst Systems, J. Appl. Polym. Sci., 109(3): 1675-1683 (2008).
[21] Qiao J., Guo M., Wang L., Liu D., Zhang X., Yu L., Song W., Liu Y., Recent Advances in Polyolefin Technology, Polym. Chem., 2 (8): 1611-1623 (2011).
[22] Vanka K., Singh G., Iyer D., Gupta V. K., DFT Study of Lewis Base Interactions with the MgCl2 Surface in the Ziegler-Natta Catalytic System: Expanding the Role of the Donors, J. Phys. Chem. C, 114(37): 15771-15781 (2010).
[24] Dashti A., Ramazani S., Hiraoka Y., Kim S. Y., Taniike T., Terano M., In Kinetic and Morphological Investigation on the Magnesium Ethoxide‐Based Ziegler‐Natta Catalyst for Propylene Polymerization Using Typical External Donors, Macromol. Symp., Wiley Online Library, 285 (1): 52-57, 2009.
[25] Andoni A., Chadwick J.C., Milani S., Niemantsverdriet H.J., Thüne P.C., Introducing a New Surface Science Model for Ziegler-Natta Catalysts: Preparation, Basic Characterization and Testing, J. Catal., 247(2): 129-136 (2007).
[26] Gao M., Liu H., Wang J., Li C., Ma J., Wei G., Novel MgCl2-Supported Catalyst Containing Diol Dibenzoate Donor for Propylene Polymerization, Polym., 45 (7): 2175-2180 (2004).
[28] Capone F., Rongo L., D’Amore M., Budzelaar P. H., Busico V., Periodic Hybrid DFT Approach (Including Dispersion) to MgCl2-Supported Ziegler–Natta Catalysts. 2. Model Electron Donor Adsorption on MgCl2 Crystal Surfaces, J. Phys. Chem. C., 117 (46): 24345-24353 (2013).
[29] Kudinova O., Kron T., Ladygina T., Kozhevnikov A., Petrov E., Novokshonova L., Polydentate Phosphine Oxides as External Electron Donors for Titanium-Magnesium Catalysts for Propylene Polymerization, Kin. Catal., 51 (2): 229-234 (2010).
[30] Kang K. K., Shiono T., Jeong Y. T., Lee D. H., Polymerization of Propylene by Using Mg(OEt)2-DNBP-TiCl4 Catalyst with Alkoxy Disilanes as External Donor, J. Appl. Polym. Sci., 71(2): 293-301 (1999).
[31] Chang H., Li H., Zheng T., Zhou Q., Zhang L., Hu Y., The Effects of New Aminosilane Compounds as External donors on Propylene Polymerization, J. Polym. Res., 21(9): 1-11 (2014).
[32] Zhou Q., Zheng T., Li H., Li Q., Zhang Y., Zhang L., Hu Y., Effects of Some New Alkoxysilane External Donors on Propylene Polymerization in MgCl2-Supported Ziegler-Natta Catalysis, Ind. Eng. Chem. Res., 53(46): 17929-17936 (2014).
[34] Taniike T., Wada T., Kouzai I., Takahashi S., Terano M., Role of Dispersion State of Ti Species in Deactivation of MgCl2-Supported Ziegler-Natta Catalysts, Macromol. Res., 18(9): 839-844 (2010).
[35] Vestberg T., Denifl P., Parkinson M., WilÉN C. E., Effects of External Donors and Hydrogen Concentration on Oligomer Formation and Chain end Distribution in Propylene Polymerization with Ziegler‐Natta Catalysts, J. Polym. Sci., Part A: Polym. Chem., 48(2): 351-358 (2010).
[36] Shen X. -R., Fu Z. -S., Hu J., Wang Q., Fan Z. -Q., Mechanism of Propylene Polymerization with MgCl2-Supported Ziegler-Natta Catalysts Based on Counting of Active Centers: The Role of External Electron Donor, J. Phys. Chem. C, 117(29): 15174-15182 (2013).
[37] Phiwkliang W., Jongsomjit B., Praserthdam P., Synergistic Effects of the ZnCl2-SiCl4 Modified TiCl4/MgCl2/THF Catalytic System on Ethylene/1-Hexene and Ethylene/1-Octene Copolymerizations., Chin. J. Polym. Sci., 32 (1): 84-91, (2014).
[38] Zahedi R., Afshar Taromi F., Mirjahanmardi S. H., Nekoomanesh Haghighi M., Jadidi K., Jamjah R. Propylene Polymerization over MgCl2‐Supported Ziegler–Natta Catalysts Containing Tri‐Ether as the Internal Donor,  Adv. Poly. Tech.37(1): 144-153 (2018).
[39] Mirjahanmardi S. H., Taromi F. A., Zahedi R., Haghighi M. N., Effects of Various Amounts of New Hepta-Ether as the Internal Donor on the Polymerization of Propylene with and without the External Donor. Polym. Sci., Ser. B., 59(6): 639-649 (2017).
[40] Zahedi R., Taromi F. A., Mirjahanmardi S. H., Haghighi M. N., Jadidi K., Jamjah R. New Penta-Ether as the Internal Donor in the MgCl2-Supported Ziegler-Natta Catalysts for Propylene PolymerizationChin. J. Polym. Sci., 34(3): 268-279 (2016).
[41] Zahedi R., Afshar Taromi F., Mirjahanmardi S. H., Nekoomanesh Haghighi M., Jamjah R., Jadidi Kh., Comparison of the Role of New Ethers and Conventional Alkoxysilanes as External Donors in the Polymerization of Propylene Using the Industrial Ziegler-Natta Catalyst., Polym. Sci. Ser. B., 58 (2):143-151 (2016).
[42] Mirjahanmardi S. H., Taromi F. A., Zahedi R., Haghighi M. N., Jamjah R., Asl G. J., Effect of Multi-Ethers and Conventional Alkoxysilanes as External Donors on the 4th Generation Ziegler-Natta Catalysts for Propylene Polymerization, Polym. Sci. Ser. B, 58(6): 619-628 (2016).