The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Alain Deffieux - One of the best experts on this subject based on the ideXlab platform.
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Retarded Anionic Polymerization: Copolymerization of Butadiene and Styrene in the Presence of Alkyllithium and n,s‐DibutylMagnesium or Triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
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retarded anionic polymerization copolymerization of butadiene and styrene in the presence of alkyllithium and n s dibutylMagnesium or triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
Stephane Carlotti - One of the best experts on this subject based on the ideXlab platform.
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Retarded Anionic Polymerization: Copolymerization of Butadiene and Styrene in the Presence of Alkyllithium and n,s‐DibutylMagnesium or Triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
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retarded anionic polymerization copolymerization of butadiene and styrene in the presence of alkyllithium and n s dibutylMagnesium or triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
Stephane Menoret - One of the best experts on this subject based on the ideXlab platform.
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Retarded Anionic Polymerization: Copolymerization of Butadiene and Styrene in the Presence of Alkyllithium and n,s‐DibutylMagnesium or Triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
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retarded anionic polymerization copolymerization of butadiene and styrene in the presence of alkyllithium and n s dibutylMagnesium or triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
Philippe Desbois - One of the best experts on this subject based on the ideXlab platform.
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Retarded Anionic Polymerization: Copolymerization of Butadiene and Styrene in the Presence of Alkyllithium and n,s‐DibutylMagnesium or Triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
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retarded anionic polymerization copolymerization of butadiene and styrene in the presence of alkyllithium and n s dibutylMagnesium or triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
A I Barabanova - One of the best experts on this subject based on the ideXlab platform.
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Retarded Anionic Polymerization: Copolymerization of Butadiene and Styrene in the Presence of Alkyllithium and n,s‐DibutylMagnesium or Triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
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retarded anionic polymerization copolymerization of butadiene and styrene in the presence of alkyllithium and n s dibutylMagnesium or triisobutylaluminium Derivatives
Macromolecular Chemistry and Physics, 2004Co-Authors: Stephane Carlotti, Stephane Menoret, A I Barabanova, Philippe Desbois, Alain DeffieuxAbstract:The influence of Lewis acid additives on the anionic butadiene polymerization using lithium as a counter ion in non-point solvent is investigated. A decrease of the polymerization rate was always observed. In the presence of n,s-Bu 2 Mg the percentage of 1,2-vinyl units increases with the [Mg]/[Li] ratio. This evolution can be explained by further complexation of lithium with free dialkylMagnesium modifying the nature of the propagating species and/or possible 1.4 to 1.2 isomerization during chain exchanges between lithium and Magnesium Derivatives. As a result a the transmetallation process, 0.5 to 1 supplementary chains are formed by Magnesium depending on the [Mg][Li] ratio. In contrast, the i Bu 3 Al/RLi system does not yield any modification of polybutadiene microstructure, which remians close to the one observed with s-Buli alone. The determination of the reactivity ratios in styrene-butadiene copolymerization shows that tapered-like copolymers are obtained in the presence of both n,s-Bu 2 Mg and i Bu 3 Al. However the Magnesium Derivative induces a lesser increase of styrene incorporation in the copolymer than the aluminium additive. The observed microstructrure and reactivity ratios support that the monomer insertion proceeds directly into heterocomplexes.
