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Harold W. Boone

Other affiliations: Clemson University
Bio: Harold W. Boone is an academic researcher from Dow Chemical Company. The author has contributed to research in topics: Polymerization & Monomer. The author has an hindex of 13, co-authored 26 publications receiving 721 citations. Previous affiliations of Harold W. Boone include Clemson University.

Papers
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Patent
23 Mar 2004
TL;DR: Group 4 metal complexes are useful as addition polymerization catalysts of the formula: (1) G 1 is a group containing from 1 to 40 atoms not counting hydrogen; (2) T is a divalent bridging group of from 10 to 30 atoms, selected from mono- or di- aryl- substituted methylene or silylene groups or mono-or di- heteroaryl-substituted methylene groups, wherein at least one such anonymy is substituted in one or both ortho- positions with a secondary or tertiary alkyl-
Abstract: Group 4 metal complexes useful as addition polymerization catalysts of the formula: (I) wherein G1 is a group containing from 1 to 40 atoms not counting hydrogen; T is a divalent bridging group of from 10 to 30 atoms not counting hydrogen, selected from mono- or di- aryl- substituted methylene or silylene groups or mono- or di- heteroaryl-substituted methylene or silylene groups, wherein at least one such aryl- or heteroaryl-substituent is substituted in one or both ortho- positions with a secondary or tertiary alkyl-group, a secondary or tertiary heteroalkyl group, a cycloalkyl group, or a heterocycloalkyl group, G2 is a C6-20 heteroaryl group containing Lewis base functionality, M is the Group 4 metal, X’’’’ is an anionic, neutral or dianionic ligand group, x’’’’ is a number from 0 to 5, and bonds, optional bonds and electron donative interactions are represented by lines, dotted lines and arrows respectively.

123 citations

Journal ArticleDOI
TL;DR: In this article, the perfluorocyclobutyl (PFCB) linkage is used for cyclopolymerization of aromatic trifluorovinyl ether (TFVE) monomers.

107 citations

Journal ArticleDOI
TL;DR: Differences in activation chemistry are manifested in the polymerization characteristics of these different precatalyst/cocatalyst combinations.
Abstract: Pyridyl-amido catalysts have emerged recently with great promise for olefin polymerization. Insights into the activation chemistry are presented in an initial attempt to understand the polymerization mechanisms of these important catalysts. The activation of C1-symmetric arylcyclometallated hafnium pyridyl-amido precatalysts, denoted Me2Hf{N(-),N,C(-)} (1, aryl = naphthyl; 2, aryl = phenyl), with both Lewis (B(C6F5)3 and [CPh3][B(C6F5)4]) and Bronsted ([HNR3][B(C6F5)4]) acids is investigated. Reactions of 1 with B(C6F5)3 lead to abstraction of a methyl group and formation of a single inner-sphere diastereoisomeric ion pair [MeHf{N(-),N,C(-)}][MeB(C6F5)3] (3). A 1:1 mixture of the two possible outer-sphere diastereoisomeric ion pairs [MeHf{N(-),N,C(-)}][B(C6F5)4] (4) is obtained when [CPh3][B(C6F5)4] is used. [HNR3][B(C6F5)4] selectively protonates the aryl arm of the tridentate ligand in both precatalysts 1 and 2. A remarkably stable [Me2Hf{N(-),N,C2}][B(C6F5)4] (5) outer-sphere ion pair is formed when the naphthyl substituent is present. The stability is attributed to a hafnium/eta(2)-naphthyl interaction and the release of an eclipsing H-H interaction between naphthyl and pyridine moieties, as evidenced through extensive NMR studies, X-ray single crystal investigation and DFT calculations. When the aryl substituent is phenyl, [Me2Hf{N(-),N,C2}][B(C6F5)4] (10) is originally obtained from protonation of 2, but this species rapidly undergoes remetalation, methane evolution, and amine coordination, giving a diastereomeric mixture of [MeHf{N(-),N,C(-)}NR3][B(C6F5)4] (11). This species transforms over time into the trianionic-ligated [Hf{N(-),C(-),N,C(-)}NR3][B(C6F5)4] (12) through activation of a C-H bond of an amido-isopropyl group. In contrast, ion pair 5 does not spontaneously undergo remetalation of the naphthyl moiety; it reacts with NMe2Ph leading to [MeHf{N(-),N}NMe2C6H4][B(C6F5)4] (7) through ortho-metalation of the aniline. Ion pair 7 successively undergoes a complex transformation ultimately leading to [Hf{N(-),C(-),N,C(-)}NMe2Ph][B(C6F5)4] (8), strictly analogous to 12. The reaction of 5 with aliphatic amines leads to the formation of a single diastereomeric ion pair [MeHf{N(-),N,C(-)}NR3][B(C6F5)4] (9). These differences in activation chemistry are manifested in the polymerization characteristics of these different precatalyst/cocatalyst combinations. Relatively long induction times are observed for propene polymerizations with the naphthyl precatalyst 1 activated with [HNMe3Ph][B(C6F5)4]. However, no induction time is present when 1 is activated with Lewis acids. Similarly, precatalyst 2 shows no induction period with either Lewis or Bronsted acids. Correlation of the solution behavior of these ion pairs and the polymerization characteristics of these various species provides a basis for an initial picture of the polymerization mechanism of these important catalyst systems.

101 citations

Journal ArticleDOI
TL;DR: It is found that insertion with either monomer leads to termination of the growing chain via beta-elimination processes, and VC and VA behave as comonomers for coordination/insertion polymerizations with ethylene.
Abstract: Since the advent of Ziegler−Natta polymerization of ethylene, attempts have been made to extend coordination polymerization to commercially important monomers with polar functionality. In this study we examined the copolymerization of perdeuterated vinyl chloride (VC) and perdeuterated vinyl acetate (VA) with ethylene using a tridentate Fe(II) dichloride pyridine diimine metal catalyst. The resulting ethylene oligomers were examined by GC/MS and ^2H NMR spectroscopy. It was shown that VC was inserted once for every ∼180 ethylene monomers and VA was inserted once for every ∼350 ethylene monomers. VC and VA behave as comonomers for coordination/insertion polymerizations with ethylene. However, we find that insertion with either monomer leads to termination of the growing chain via β-elimination processes. The deuterium atoms are exclusively located at the olefin terminus for each of the monomers.

54 citations


Cited by
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Journal ArticleDOI
TL;DR: Akifumi Nakamura’s research interests include synthetic organic chemistry, organometallic chemistry, computational chemistry, and polymer chemistry.
Abstract: numerous polyethylene or polypropylene compounds have been synthesized by metal-catalyzed coordination-insertion polymerization. On the other hand, organometallic catalysts * To whom correspondence should be addressed. E-mail: nozaki@chembio.t.utokyo.ac.jp. Akifumi Nakamura (left) was born in 1984 in Kanagawa, Japan. He received his B.S. degree in 2007 and M.S. degree in 2009 from the University of Tokyo under the guidance of Professor Kyoko Nozaki. During that time he joined Professor Keiji Morokuma’s group at Kyoto University as a visiting student. In 2009, he started his Ph.D. study at the University of Tokyo under the guidance of Professor Kyoko Nozaki. He is also a research fellow of the Japan Society for the Promotion of Science. His research interests include synthetic organic chemistry, organometallic chemistry, computational chemistry, and polymer chemistry.

690 citations

Journal ArticleDOI
TL;DR: The aim of this review was to establish ana-C2v-Ligated Catalysts as a stand-alone database of Lanthanide Complexes with a focus on the latter stages of their development in the second half of the 1990s.
Abstract: 1.3. Scope of Review 5161 2. Methacrylate Polymerization 5161 2.1. Lanthanide Complexes 5161 2.1.1. Nonbridged Lanthanocenes 5161 2.1.2. ansa-Lanthanocenes 5164 2.1.3. Half-Lanthanocenes 5166 2.1.4. Non-lanthanocenes 5166 2.2. Group 4 Metallocenes 5170 2.2.1. Nonbridged Catalysts 5170 2.2.2. ansa-C2v-Ligated Catalysts 5173 2.2.3. ansa-C2-Ligated Catalysts 5173 2.2.4. ansa-C1-Ligated Catalysts 5176 2.2.5. ansa-Cs-Ligated Catalysts 5177 2.2.6. Constrained Geometry Catalysts 5178 2.2.7. Half-Metallocene Catalysts 5180 2.2.8. Supported Catalysts 5180 2.3. Other Metallocene Catalysts 5180 2.4. Nonmetallocene Catalysts 5181 2.4.1. Group 1 and 2 Catalysts 5181 2.4.2. Group 13 Catalysts 5183 2.4.3. Group 14 Catalysts 5186 2.4.4. Transition-Metal Catalysts 5187 3. Acrylate Polymerization 5188 3.1. Lanthanocenes 5188 3.2. Group 4 Metallocenes 5189 3.3. Nonmetallocenes 5190 4. Acrylamide and Methacrylamide Polymerization 5191 4.1. Acrylamides 5191 4.2. Methacrylamides 5192 4.3. Asymmetric Polymerization 5193 5. Acrylonitrile and Vinyl Ketone Polymerization 5196 5.1. Acrylonitrile 5196 5.2. Vinyl Ketones 5196 6. Copolymerization 5197 6.1. Polar-Nonpolar Block Copolymers 5197 6.2. Polar-Nonpolar Random Copolymers 5199 6.3. Polar-Polar Copolymers 5204 7. Ion-Pairing Polymerization 5206 8. Summary and Outlook 5208 9. Acknowledgments 5208 10. References 5208

460 citations

Journal ArticleDOI
TL;DR: All-Polyolefin Composites Markus Stürzel,† Shahram Mihan,‡ and Rolf Mülhaupt*,†,§ †Freiburg Materials Research Center and Institute for Macromolecular Chemistry.
Abstract: All-Polyolefin Composites Markus Stürzel,† Shahram Mihan,‡ and Rolf Mülhaupt*,†,§ †Freiburg Materials Research Center (FMF) and Institute for Macromolecular Chemistry, Albert-Ludwigs-University Freiburg, Stefan-Meier-Strasse 31, D-79104 Freiburg, Germany ‡Basell Polyolefine GmbH, Catalyst Systems, Industriepark Hoechst, D-65926 Frankfurt am Main, Germany Sustainability Center Freiburg, Ecker-Strasse 4, D-79104 Freiburg, Germany

440 citations

Patent
17 Mar 2005
TL;DR: In this article, a multi-block copolymer is defined for use in forming a multinode copolym, containing two or more segments or blocks differing in chemical or physical properties, and a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (a) a first metal complex olefin polymerization catalyst, (b) a second metal complex OLEF polymerisation catalyst capable of preparing polymers differing from the polymer prepared by catalyst under equivalent polymerization conditions, and (
Abstract: A composition for use in forming a multi-block copolymer, said copolymer containing therein two or more segments or blocks differing in chemical or physical properties, a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

377 citations