Thesis POLY(ISOBUTYL VINYL ETHER) GENERATION VIA DINUCLEAR HALF-TITANOCENES AND ETHYLENE COPOLYMERIZATION STUDIES BY USE OF DINUCLEAR CONSTRAINED GEOMETRY CATALYST WITH BRANCHED XYLENE BRIDGE The Graduate School of Yeungnam University Department of Chemical Engineering and Technology Major in Chemical Engineering and Technology NGUYEN THI LE THANH Advisor: Professor Seok Kyun Noh December 2009 Ph. Thesis POLY(ISOBUTYL VINYL ETHER) GENERATION VIA DINUCLEAR HALF-TITANOCENES AND ETHYLENE COPOLYMERIZATION STUDIES BY USE OF DINUCLEAR CONSTRAINED GEOMETRY CATALYST WITH BRANCHED XYLENE BRIDGE Advisor: Professor Seok Kyun Noh Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2009 The Graduate School of Yeungnam University Department of Chemical Engineering and Technology Major in Chemical Engineering and Technology NGUYEN THI LE THANH Nguyen Thi Le Thanh’s Ph.D Thesis is approved by Committee members December 2009 The Graduate School of Yeungnam University Acknowledgments Writing a PhD thesis is a great experience. It has even more experience of a new academic life and a new culture when following PhD course abroad. My PhD course in South Korea was finished, and I have been ready to come back Vietnam to build my future.
So, I am glad to complete it by remembering many wonderful people who contributed to the achievements in various ways. Looking back on the time that I spent a Yeungnam University to study and finish this thesis, I must admit that I enjoyed doing this research very much, even though it was not easy. My very special thank to Professor Seok Kyun Noh at School of Display and Chemical Engineering, who gave me a chance to do research on metallocene polymerization under his supervision. His expertise, motivation, enthusiasm, understanding, and patience, taken together, make him a great mentor.
Thank you for directing me through my research and for all your help during my stay. Many thanks go to Professors and lecturers at Yeungnam University, in general, and School of Display and Chemical Engineering, in particular, who gave me valuable lectures and advices. Especially, I would like to express my sincere appreciation to Professor Suk Gyu Lee, my husband’s supervisor, for his valuable and numerous help to our living in Korea. I would like to thank the members of my thesis committee, Professor Seung Woo Lee, Professor Yeong Soon Jegal, Professor Won Seok Lyoo and Professor Dong Ho Lee to kindly for their time, interest, and helpful suggestions and comments.
In my attempted measurements of polymers, I am particularly indebted to Dr. Lee from Analytical Center at Yeungnam University, Ms. Soon Mo Choi from KOTMI, and technicians at Hanhwa, LG, and KPIC companies who gave me the best condition of measurement, advised me in analysis of measurement results, and tried hard to deal with the stickiness of my polymers. -i- I gratefully acknowledge the funding sources from Brain Korea (BK) 21 Project and Cluster that supported my works and other research activities.
I consider myself fortunate to be with all of my colleagues in Precision Polymerization Research Laboratory and neighbor laboratories: Kyung Sik, Xue, Dan Que, Ba Linh, Ji Yoon, Hyun Suk, Eung Keung, Jung Suk, Sun Hee, Seok Young, Khan, Hedan, Nhat Thanh, Dieu Huyen, Chen, and too many others to put all your names here. It is my pleasure to work and discuss with you, and receive your help both in research and life. One might come and leave, and even we are far from each others, our good memories and friendship will be never out of my heart. With great appreciation, I shall acknowledge Hochiminh city University of Technology (Vietnam National University, Hochiminh city), Faculty of Materials Technology for the permission to study abroad and always keeping the door opened to me; Professor Nguyen Huu Nieu and Professor Do Thanh Thanh Son, who introduced and encouraged me to study polymerization in Yeungnam University.
For the non-scientific side, I would also like to take this opportunity to thank Vietnamese students studying at Yeungnam University as well as other universities in Korea for such kind help, encouragement, friendship, and happy times. I will never forget four years of living with a solidary and affectionate community of Vietnamese students in Yeungnam University. You helped me to overcome the difficulties of living abroad. And last but not least, I deeply thank Doctor Jung Tae Park for his patience to take care of my health.
I would like to express my gratitude to my parents. My hard-working parents have sacrificed their lives for my sisters and myself and provided unconditional love and care. Especially, I am lucky to have my youngest sister Le Nhon, who has good knowledge on organics and polymer, right here and appreciate much her help. I am also very grateful to my husband’s family.
My parents-in-law have dealt with my personal issues in Vietnam, encouraged me constantly and my brother-in-law is a wonderful model of scientific passion. Finally, my husband is one extraordinary person deserving most of the - ii - acknowledgements. I am sure that this thesis could not have been accomplished without him. For all the times I was unsure of myself, suffered from health weakling, stressed from the workload, or doubtful of my plans, he is always right beside me with listening ears, loving smiles, right words to improve my condition and give me the feeling of warmth, hope and peace.
I dedicate this thesis to him. December, 2009 Nguyen Thi Le Thanh Yeungnam University, South Korea. - iii - Contents ACKNOWLEDGMENTS. iv LIST OF TABLES.
vii LIST OF SCHEMES. ix LIST OF FIGURES. x LIST OF ABBREVIATIONS. xiv CHAPTER 1 INTRODUCTION TO DINUCLEAR METALLOCENE.
MECHANISM OF COORDINATION POLYMERIZATION. THE SCOPE OF THESIS. 16 CHAPTER 2 SYNTHESIS OF NEW DCGC WITH DIFFERENT BRANCHES ON XYLENE BRIDGE. Synthesis of xylene bridge.
Synthesis of {TiCl2 [N(tBu) Si(Me)2]C9H5}2{(CH2)n[(R)2C6H2] (CH2)n}, 1-6, metathesis reaction. 33 - iv - CHAPTER 3 POLYMERIZATION OF ISOBUTYL VINYL ETHER CATALYSED BY DINUCLEAR HALF-TITANOCENES. RESULTS AND DISCUSSIONS. Polymerization of IBVE.
Molecular weight of PIBVE. Stereoregularity of PIBVE. 53 CHAPTER 4 ETHYLENE/STYRENE COPOLYMERIZATION USING NEW DCGC. RESULTS AND DISCUSSIONS.
Effect of catalyst structure on catalytic activity. Effect of catalyst structure on styrene content. Effect of catalyst structure on molecular weight. 73 CHAPTER 5 ETHYLENE/1-HEXENE COPOLYMERIZATION USING NEW DCGC.
RESULTS AND DISCUSSIONS. Effect of the polymerization conditions. Effect of the catalyst structure. 104 - vi - List of Tables Table 3.1 Results of IBVE polymerization by use of dinuclear half-titanocenes at –100C 39 Table 3.2 Results of IBVE polymerization by use of dinuclear half-titanocenes at –300C 40 Table 4.1 The catalytic activity results obtained at various styrene concentrations at 400C 59 Table 4.2 The catalytic activity results obtained at various styrene concentrations at 700C 60 Table 4.3 The styrene content results obtained at various styrene concentrations at 400C 65 Table 4.4 The styrene content results obtained at various styrene concentrations at 700C 66 Table 4.5 Molecular weight of ethylene/styrene copolymers at 400C 68 Table 4.6 Molecular weight of ethylene/styrene copolymers at 700C 69 Table 5.1 Correlation of catalytic activity with concentration of catalyst 77 Table 5.2 Catalytic activity results obtained at various monomer feed ratios [H]/[E] at 400C 80 Table 5.3 Catalytic activity results obtained at various monomer feed ratios [H]/[E] at 500C and 300C 81 Table 5.4 1-Hexene content results obtained at various monomer feed ratios [H]/[E] at 400C and 300C 83 Table 5.5 1-Hexene content results obtained at various monomer feed ratios [H]/[E] at 500C and 300C 84 Table 5.6 Heat of fusion and degree of crystallization of the samples measured by DSC 88 Table 5.7 Molecular weight of copolymers 92 - vii - Table 5.8 Chemical shift assignments in the 13C-NMR spectra of poly(ethylene-co-1-hexene) 96 Table 5.9 Monomer sequence distributions of poly(ethylene-co-1-hexene) obtained by DCGC and Dow CGC at monomer feed ratio [H]/[E] = 4, 400C 98 - viii - List of Schemes Scheme 1.1 The common examples of metallocene complexes 2 Scheme 1.2 Aryloxide and ketimide titanium half-sandwich catalyst precursors used for styrene–ethylene copolymerization 3 Scheme 1.3 The common examples of dinuclear metallocene complexes 6 Scheme 1.4 Our dinuclear metallocenes 9 Scheme 1.5 Our dinuclear metallocenes (continue) 10 Scheme 1.6 Our dinuclear metallocenes (continue) 11 Scheme 1.7 The coordination polymerization of olefins 12 Scheme 1.8 Mechanism for monomer insertion in α-olefin polymerization with coordination catalysts 13 Scheme 2.1 The designed structures 21 Scheme 2.2 The route of synthesizing catalysts 23 Scheme 2.3 Synthesis of ligands 24 Scheme 3.1 Scheme of polymerization of PIBVE and structure of the catalysts 1 to 5 38 Scheme 3.2 Intramolecular interaction between two metal centers in dinuclear half-titanocenes 43 Scheme 4.1 Intramolecular interaction between branch and active centers 61 Scheme 5.1 β-H elimination process 90 - ix - List of Figures Figure 3.1 Correlation of conversion vs the polymerization time with the catalysts 1 to 5 at –100C 41 Figure 3.2 Correlation of conversion with the polymerization time with the catalysts 1 to 5 at –300C 42 Figure 3.3 Effect of temperature on conversion of IBVE polymerization vs time using dinuclear half-titanocene catalyst 2 44 Figure 3.4 Mn and PDI vs conversion for polymerization of IBVE using dinuclear half-titanocene catalyst 2 at three different temperatures 46 Figure 3.5 Mn and PDI vs conversion for polymerization of IBVE using dinuclear half-titanocene catalysts at –100C 47 Figure 3.6 Mn and PDI vs conversion for polymerization of IBVE using dinuclear half-titanocene catalysts at –300C 48 13 Figure 3.7 C-NMR spectrum of PIBVE using catalysts 1, 2, 3, 4, 5 system in CDCl3 at 500C 51 1 Figure 4.1 H-NMR spectra of typical ethylene-styrene copolymer sample (Run 8) 63 13 Figure 4.2 C-NMR spectra of ethylene-styrene copolymer samples from run 1-7 (catalyst 1 - 6) and Dow CGC) 67 Figure 5.1 Correlation of catalytic activity with polymerization time 78 1 Figure 5.2 H-NMR spectrum of 1-hexene copolymer prepared by catalyst 2 with: (a) [H]/[E] = 2 (24.7 mol%) at 400C 85 1 Figure 5.3 H-NMR spectrum of 1-hexene copolymer prepared by: (a) catalyst 1 ; (b) catalyst 2; (c) catalyst 3; (d) Dow catalyst at 400C, [H]/[E] = 4 86 Figure 5.4 Variation of 1-hexene contents with [H]/[E] ratios in feed at 400C 86 Figure 5.5 DSC thermograms of the copolymers produced with catalyst 2 at 400C 89 Figure 5.6 DSC thermograms of the copolymers produced at monomer feed ratio -x- [H]/[E] = 2 and 400C 89 Figure 5.7 The approximate calculated structure of catalysts at minimized energy state 94 13 Figure 5.8 C-NMR spectrum of ethylene/1-hexene copolymers obtained by a- catalyst Dow; b- catalyst 1; c- catalyst 2; d- catalyst 3; e- catalyst 4 at monomer feed ratio [H]/[E] = 4 and 400C 97 - xi - List of Abbreviations APP Atactic Polypropylene Cat.
Catalyst CGC Constrained Geometry Catalyst Cp Cyclopentadienyl DCGC Dinuclear Constrained Geometry Catalyst DSC Differential Scanning Calorimetry E Ethylene ESI Ethylene – Styrene Interpolymer GPC Gel Permeation Chromatography H 1-hexene HDPE High Density Polyethylene IBVE Isobutyl Vinyl Ether IPP Isotactic Polypropylene LDPE Low Density Polyethylene LLDPE Linear Low Density Polyethylene Mη Viscosity Averaged Molecular Weight MAO Methylaluminoxane Mn Molecular Weight Mt-C Metal – Carbon Mt-Et Metal – Ethyl Mw Molecular Weight MWD Molecular Weight Distribution NMR Nuclear Magnetic Resonance PIBVE Poly(Isobutyl Vinyl Ether) PDI Polydispersity Index PE Polyethylene - xii - PP Polypropylene S Styrene SPP Syndiotactic Polypropylene SPS Syndiotactic Polystyrene t polymerization time TCB 1,2,4-Trichlorobenzene THF Tetrahydrofuran Tp polymerization temperature vs versus - xiii - Abstract In recent years, a variety of dinuclear half-metallocene catalysts has been developed rapidly for olefin polymerization because cooperative effects between two metal centers, ligand structures and the nature of the bridge can tailor polymer properties, such as molecular weight, molecular weight distribution as well as stereochemistry through. However, these catalysts have rarely been applied to polymerize polar vinyl monomers. So, we synthesize a series of half dinuclear metallocene [(C5H4)2(CH2)n][(TiCl3)2] [2(n=3), 3(n=6)], and [(C5H4)2(CH2)n][(TiCl2OR)2] [4(n=3), 5(n=6)] with different polymethylene bridges.