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Eli Ruckenstein - One of the best experts on this subject based on the ideXlab platform.
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Novel Monodisperse Functional (Co)polymers Based on the Selective Living Anionic Polymerization of a New Bifunctional Monomer, trans,trans-1-Methacryloyloxy-2,4-hexadiene
Macromolecules, 2001Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:A new Bifunctional Monomer, trans,trans-1-methacryloyloxy-2,4-hexadiene (MAHE), was prepared through the reaction between the sodium salt of 2,4-hexadien-1-ol and methacryloyl chloride. Using 1,1-diphenylhexyllithium (DPHL) as initiator, in THF, in the presence of LiCl ([LiCl]/[DPHL]0 = 3), at −70 °C, the anionic polymerization of MAHE proceeded quantitatively, generating monodisperse polymers (Mw/Mn = 1.04−1.05) with well-controlled molecular weights. Under similar conditions, well-defined block copolymers with controlled molecular weights and compositions as well as very narrow molecular weight distributions (Mw/Mn = 1.04−1.06) were prepared by the anionic block copolymerization of MAHE and MMA, regardless of the polymerization sequence (MAHE followed by MMA or vice versa). Similarly, the copolymers resulting from the random copolymerization of these two Monomers possessed monodispersity (Mw/Mn = 1.04−1.05), regardless of the feed amount ratio. Further, block copolymers of St and MAHE with various compo...
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selective living anionic polymerization of a novel Bifunctional Monomer 4 vinylphenyl 1 butene and the preparation of uniform size functional polymers and amphiphilic block copolymers
Macromolecules, 1999Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:A novel Bifunctional Monomer, namely, 4-(vinylphenyl)-1-butene (VSt), was prepared by the coupling reaction between vinylbenzyl chloride and allylmagnesium chloride with a high yield (93%) and Monomer purity. This Monomer contains both a styrene type and a 1-butene type CC double bond. The former double bond can be selectively polymerized by anionic polymerization to generate a polymer with a polystyrene [poly(St)] backbone and functional butenyl side chains. The effects of the initiator, temperature, and solvent were investigated, and the optimum conditions for the selective living anionic polymerization of this Monomer were determined. Using n-BuLi as initiator, in a mixture of toluene and tetrahydrofuran (5:1−2:1), at −40 °C, VSt could undergo anionic polymerization in a living manner without cross-linking and any other side reactions. The polymer thus obtained possesses a controlled molecular weight and a very narrow molecular weight distribution (Mw/Mn = 1.03−1.05). The quantitative presence of the u...
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Well-Defined Graft Copolymers Based on the Selective Living Anionic Polymerization of the Bifunctional Monomer 4-(Vinylphenyl)-1-butene
Macromolecules, 1999Co-Authors: Eli Ruckenstein, Hongmin ZhangAbstract:The anionic copolymerization of the Bifunctional Monomer 4-(vinylphenyl)-1-butene (VSt) with styrene (St) was carried out in a mixture of toluene and tetrahydrofuran (THF), using n-BuLi as initiator, at −40 °C. During this process, the styrene type CC bond of VSt was selectively polymerized, and the other one in its butenyl moiety remained unchanged. The molecular weight and the composition of the resulting copolymer could be well-controlled, and its molecular weight distribution was very narrow (Mw/Mn = 1.03−1.04). The unreacted butenyl groups of the VSt units were further reacted with chlorodimethylsilane, generating another functional copolymer with reactive chlorodimethylbutylsilyl side chains. This functional polymer was used as a backbone polymer and reacted with the anionic living polymers of St, isoprene (Is), or methyl methacrylate (MMA). This coupling reaction resulted in the formation of well-defined graft (co)polymers with a poly(St) backbone and either poly(St) or poly(Is) or poly(MMA) side c...
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Graft Copolymers by Combined Anionic and Cationic Polymerizations Based on the Homopolymerization of a Bifunctional Monomer
Macromolecules, 1998Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:The Bifunctional Monomer 2-(vinyloxy)ethyl methacrylate (VEMA) was polymerized both anionically and cationically. Using 1,1-diphenylhexyllithium (DPHL) as initiator, tetrahydrofuran (THF) as solvent and the low temperature of −60 °C, the CC double bond of the methacryloyl group of VEMA underwent smoothly anionic polymerization, without cross-linking or side reactions. The polymer had a controlled molecular weight and a narrow molecular weight distribution (Mw/Mn = 1.06−1.12). On the other hand, the CC double bond of the vinyloxy group of VEMA can undergo cationic polymerization. A polymer with controlled molecular weight and narrow molecular weight distribution (Mw/Mn = 1.11−1.13) was prepared using 2-[1-acetoxyethoxy]ethyl methacrylate (4)/EtAlCl2 as initiator in the presence of THF, a weak Lewis base. Two methods were employed to prepare graft copolymers. (A) The anionically prepared polymer of VEMA was separated from solution after quenching the polymerization and purified by freeze-drying; then the vi...
Hongmin Zhang - One of the best experts on this subject based on the ideXlab platform.
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Novel Monodisperse Functional (Co)polymers Based on the Selective Living Anionic Polymerization of a New Bifunctional Monomer, trans,trans-1-Methacryloyloxy-2,4-hexadiene
Macromolecules, 2001Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:A new Bifunctional Monomer, trans,trans-1-methacryloyloxy-2,4-hexadiene (MAHE), was prepared through the reaction between the sodium salt of 2,4-hexadien-1-ol and methacryloyl chloride. Using 1,1-diphenylhexyllithium (DPHL) as initiator, in THF, in the presence of LiCl ([LiCl]/[DPHL]0 = 3), at −70 °C, the anionic polymerization of MAHE proceeded quantitatively, generating monodisperse polymers (Mw/Mn = 1.04−1.05) with well-controlled molecular weights. Under similar conditions, well-defined block copolymers with controlled molecular weights and compositions as well as very narrow molecular weight distributions (Mw/Mn = 1.04−1.06) were prepared by the anionic block copolymerization of MAHE and MMA, regardless of the polymerization sequence (MAHE followed by MMA or vice versa). Similarly, the copolymers resulting from the random copolymerization of these two Monomers possessed monodispersity (Mw/Mn = 1.04−1.05), regardless of the feed amount ratio. Further, block copolymers of St and MAHE with various compo...
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selective living anionic polymerization of a novel Bifunctional Monomer 4 vinylphenyl 1 butene and the preparation of uniform size functional polymers and amphiphilic block copolymers
Macromolecules, 1999Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:A novel Bifunctional Monomer, namely, 4-(vinylphenyl)-1-butene (VSt), was prepared by the coupling reaction between vinylbenzyl chloride and allylmagnesium chloride with a high yield (93%) and Monomer purity. This Monomer contains both a styrene type and a 1-butene type CC double bond. The former double bond can be selectively polymerized by anionic polymerization to generate a polymer with a polystyrene [poly(St)] backbone and functional butenyl side chains. The effects of the initiator, temperature, and solvent were investigated, and the optimum conditions for the selective living anionic polymerization of this Monomer were determined. Using n-BuLi as initiator, in a mixture of toluene and tetrahydrofuran (5:1−2:1), at −40 °C, VSt could undergo anionic polymerization in a living manner without cross-linking and any other side reactions. The polymer thus obtained possesses a controlled molecular weight and a very narrow molecular weight distribution (Mw/Mn = 1.03−1.05). The quantitative presence of the u...
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Well-Defined Graft Copolymers Based on the Selective Living Anionic Polymerization of the Bifunctional Monomer 4-(Vinylphenyl)-1-butene
Macromolecules, 1999Co-Authors: Eli Ruckenstein, Hongmin ZhangAbstract:The anionic copolymerization of the Bifunctional Monomer 4-(vinylphenyl)-1-butene (VSt) with styrene (St) was carried out in a mixture of toluene and tetrahydrofuran (THF), using n-BuLi as initiator, at −40 °C. During this process, the styrene type CC bond of VSt was selectively polymerized, and the other one in its butenyl moiety remained unchanged. The molecular weight and the composition of the resulting copolymer could be well-controlled, and its molecular weight distribution was very narrow (Mw/Mn = 1.03−1.04). The unreacted butenyl groups of the VSt units were further reacted with chlorodimethylsilane, generating another functional copolymer with reactive chlorodimethylbutylsilyl side chains. This functional polymer was used as a backbone polymer and reacted with the anionic living polymers of St, isoprene (Is), or methyl methacrylate (MMA). This coupling reaction resulted in the formation of well-defined graft (co)polymers with a poly(St) backbone and either poly(St) or poly(Is) or poly(MMA) side c...
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Graft Copolymers by Combined Anionic and Cationic Polymerizations Based on the Homopolymerization of a Bifunctional Monomer
Macromolecules, 1998Co-Authors: Hongmin Zhang, Eli RuckensteinAbstract:The Bifunctional Monomer 2-(vinyloxy)ethyl methacrylate (VEMA) was polymerized both anionically and cationically. Using 1,1-diphenylhexyllithium (DPHL) as initiator, tetrahydrofuran (THF) as solvent and the low temperature of −60 °C, the CC double bond of the methacryloyl group of VEMA underwent smoothly anionic polymerization, without cross-linking or side reactions. The polymer had a controlled molecular weight and a narrow molecular weight distribution (Mw/Mn = 1.06−1.12). On the other hand, the CC double bond of the vinyloxy group of VEMA can undergo cationic polymerization. A polymer with controlled molecular weight and narrow molecular weight distribution (Mw/Mn = 1.11−1.13) was prepared using 2-[1-acetoxyethoxy]ethyl methacrylate (4)/EtAlCl2 as initiator in the presence of THF, a weak Lewis base. Two methods were employed to prepare graft copolymers. (A) The anionically prepared polymer of VEMA was separated from solution after quenching the polymerization and purified by freeze-drying; then the vi...
V. G. Syromyatnikov - One of the best experts on this subject based on the ideXlab platform.
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lc photoaligning polymer prepared via selective polymerization of Bifunctional Monomer with o methacryloyl and styrene type double bonds
Molecular Crystals and Liquid Crystals, 2014Co-Authors: L. O. Vretik, V. Zagniy, O. A. Nikolaeva, V. G. SyromyatnikovAbstract:Phenylene-containing Monomer 1 possessing O-methacryloyl and styrene double bonds with different reactivities in radical polymerization was designed as new type of Bifunctional Monomers suitable for preparation of LC photoaligning alkene-functionalized polymers. To elucidate an individual contribution of double bond of each type into kinetics of Bifunctional Monomers polymerization, thermo- and photo-induced polymerization of model Monomers were investigated and compared. Polymer poly-1 obtained by thermo-induced radical polymerization demonstrated high efficiency of LC ZLI 2293 photoalignment.
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LC Photoaligning Polymer Prepared via Selective Polymerization of Bifunctional Monomer with O-Methacryloyl and Styrene–Type Double Bonds
Molecular Crystals and Liquid Crystals, 2014Co-Authors: L. O. Vretik, V. Zagniy, O. A. Nikolaeva, V. G. SyromyatnikovAbstract:Phenylene-containing Monomer 1 possessing O-methacryloyl and styrene double bonds with different reactivities in radical polymerization was designed as new type of Bifunctional Monomers suitable for preparation of LC photoaligning alkene-functionalized polymers. To elucidate an individual contribution of double bond of each type into kinetics of Bifunctional Monomers polymerization, thermo- and photo-induced polymerization of model Monomers were investigated and compared. Polymer poly-1 obtained by thermo-induced radical polymerization demonstrated high efficiency of LC ZLI 2293 photoalignment.
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Reactivity of double bonds of substituted p-(methacryloyloxy)-N-phenylmaleimides in free-radical polymerization
Polymer Science Series A, 2007Co-Authors: L. Yu. Grishchuk, L. A. Vretik, V. G. SyromyatnikovAbstract:The thermoinduced free-radical polymerization of model systems, namely, methyl methacrylate and N -phenylmaleimide derivatives, has been studied. It has been shown that, in the polymerization of p -(methacryloyloxy)- N -phenylmaleimides, the yield of the polymer and its molecular-mass distribution (mono-or bimodal) and polydispersity depend on the degree of substitution and the nature of a substituent in a double bond of a maleimide fragment. The structure of the maleimide fragment, in turn, determines its capability to copolymerize with the methacryloyl group of a Bifunctional Monomer as well as the occurrence of chain-transfer and termination reactions.
Christian Pichot - One of the best experts on this subject based on the ideXlab platform.
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Side‐Product of N‐Acryloyloxysuccinimide Synthesis or Useful New Bifunctional Monomer?
Macromolecular Bioscience, 2001Co-Authors: Franck D'agosto, Marie-thérèse Charreyre, Christian PichotAbstract:During the synthesis of the N-acryloxysuccinimide (NAS) Monomer, we observed the formation of a by-product, resulting from the condensation of two NAS molecules via a Michael addition. Due to its bulky structure, this new Bifunctional Monomer shows a very poor ability to homopolymerize. On the contrary, it readily copolymerizes with N-acryloylmorpholine (NAM), an hydrophilic acrylamide derivative, leading to functional polymer chains exhibiting a wide range of solubility and a high potential for biomolecule covalent binding.
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side product of n acryloyloxysuccinimide synthesis or useful new Bifunctional Monomer
Macromolecular Bioscience, 2001Co-Authors: Franck Dagosto, Marie-thérèse Charreyre, Christian PichotAbstract:During the synthesis of the N-acryloxysuccinimide (NAS) Monomer, we observed the formation of a by-product, resulting from the condensation of two NAS molecules via a Michael addition. Due to its bulky structure, this new Bifunctional Monomer shows a very poor ability to homopolymerize. On the contrary, it readily copolymerizes with N-acryloylmorpholine (NAM), an hydrophilic acrylamide derivative, leading to functional polymer chains exhibiting a wide range of solubility and a high potential for biomolecule covalent binding.
Geoffrey W. Coates - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Alkaline Anion Exchange Membranes with Chemically Stable Imidazolium Cations: Unexpected Cross-Linked Macrocycles from Ring-Fused ROMP Monomers
Macromolecules, 2018Co-Authors: Kristina M. Hugar, Geoffrey W. CoatesAbstract:In order to prepare base-stable, mechanically strong, and synthetically feasible alkaline anion exchange membranes (AAEMs) for applications in alkaline fuel cells, an imidazolium-fused cyclooctene Monomer was prepared and subjected to ring-opening metathesis polymerization (ROMP) conditions. Surprisingly, macrocyclic oligomers were obtained instead of high molecular weight polymers. High-performance AAEMs were synthesized by using a Bifunctional Monomer to cross-link the macrocycles. The resultant AAEMs showed high ionic conductivities (σOH– = 59 mS/cm at 50 °C), robust mechanical properties, and excellent alkaline stabilities.
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Synthesis of Alkaline Anion Exchange Membranes with Chemically Stable Imidazolium Cations: Unexpected Cross-Linked Macrocycles from Ring-Fused ROMP Monomers
2018Co-Authors: Wei You, Kristina M. Hugar, Geoffrey W. CoatesAbstract:In order to prepare base-stable, mechanically strong, and synthetically feasible alkaline anion exchange membranes (AAEMs) for applications in alkaline fuel cells, an imidazolium-fused cyclooctene Monomer was prepared and subjected to ring-opening metathesis polymerization (ROMP) conditions. Surprisingly, macrocyclic oligomers were obtained instead of high molecular weight polymers. High-performance AAEMs were synthesized by using a Bifunctional Monomer to cross-link the macrocycles. The resultant AAEMs showed high ionic conductivities (σOH– = 59 mS/cm at 50 °C), robust mechanical properties, and excellent alkaline stabilities