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Fanny Bonnet - One of the best experts on this subject based on the ideXlab platform.
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bis phenolate amine supported lanthanide borohydride complexes for styrene and trans 1 4 isoprene co polymerisations
Dalton Transactions, 2015Co-Authors: Fanny Bonnet, Marc Visseaux, Hellen E Dyer, Yassine El Kinani, Chjt Carin Dietz, Pascal Roussel, Marc Bria, Philippe Zinck, Philip MountfordAbstract:New bis(phenolate)amine-supported neodymium borohydride complexes and their previously reported samarium analogues were tested as catalysts for the polymerisation of styrene and isoprene. Reaction of Na2O2NL (L = py, OMe, NMe2) with Nd(BH4)3(THF)3 afforded the borohydride complexes Nd(O2NL)(BH4)(THF) (L = py (1-Nd), OMe (2-Nd), NMe2 (3-Nd)). Complex 1-Nd has shown a propensity to form phenolate-O-bridged dimer [Nd(μ-O2Npy)(BH4)]2 (1′-Nd) as previously observed with the samarium analogues Sm(O2NL)(BH4)(THF) (L = py or Pr). X-ray structures of 1′-Nd and 2-Nd were determined and are presented. The neodymium borohydride complexes 1-Nd to 3-Nd and their samarium analogues Sm(O2NL)(BH4)(THF)x (L = py (1-Sm), OMe (2-Sm), NMe2 (3-Sm), Pr (4-Sm)) were tested as catalysts for the polymerisation of isoprene and styrene in the presence of n-butylethylmagnesium (Mg(nBu)(Et)). All complexes were found to be active for the polymerisation of isoprene in these conditions, leading to Polyisoprene up to 95.1% trans-1,4 stereoregular. They were also found to be active for the polymerisation of styrene leading to atactic polystyrene in all cases. Interestingly, samarium-based complexes were found to be more active than the neodymium ones toward this latter monomer, in sharp contrast to what is usually observed with rare earth borohydride complexes. The structure of both trans-Polyisoprenes and polystyrenes obtained were studied in detail by MALDI-ToF analysis in order to better understand the polymerisation mechanisms. The coordinative chain transfer polymerisation (CCTP) of both monomers was further conducted using Mg(nBu)(Et) as transfer agent. Finally, the statistical copolymerisation of isoprene and styrene was examined using these catalytic systems, leading to the formation of poly[(trans-1,4-isoprene)-co-styrene] with up to 39% of styrene moieties inserted in a highly trans-1,4-stereoregular Polyisoprene.
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highly trans stereospecific isoprene polymerization by neodymium borohydrido catalysts
Macromolecules, 2005Co-Authors: Fanny Bonnet, Marc Visseaux, And Angela Pereira, Denise BarbierbaudryAbstract:Highly stereospecific polymerization of isoprene was achieved using borohydridoneodymium complexes. In combination with stoichiometric amounts of dialkylmagnesium, Nd(BH4)3(THF)3 (1) and Cp*‘Nd(BH4)2(THF)2 (2) (Cp*‘ = C5Me4nPr) afford very efficient catalysts. The activity reaches 37300 (g of Polyisoprene/mol of Nd)/h. Half-lanthanidocene 2 gives rise to Polyisoprene, 98.5% trans-regular, the highest content yet described for a homogeneous organometallic catalyst. NMR experiments argue for the formation of bimetallic Nd(μ-BH4)Mg active species.
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Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts
Macromolecules, 2005Co-Authors: Fanny Bonnet, Marc Visseaux, Angela Pereira, Denise Barbier-baudryAbstract:Highly stereospecific polymerization of isoprene was achieved using borohydrido neodymium complexes. In combination with stoichiometric amounts of dialkylmagnesium, Nd(BH4)3(THF)3 (1) and Cp*'Nd(BH4)2(THF)2 (2) (Cp*' = C5Me4nPr) afford very efficient catalysts. Activity reaches 37300 g Polyisoprene/mol Nd/h. Half-lanthanidocene 2 gives rise to Polyisoprene 98.5 % trans-regular, the highest content yet described for a homogeneous organometallic catalyst. NMR experiments argue for the formation of bimetallic Nd(m-BH4)Mg active species.
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diene polar monomer copolymers compatibilisers for polar non polar polymer blends a controlled block copolymerisation with a single site component samarocene initiator
Macromolecular Chemistry and Physics, 2002Co-Authors: Denise Barbierbaudry, Fanny Bonnet, A Dormond, Eric Finot, Marc VisseauxAbstract:A well-controlled two-step process, the polymerisation of isoprene or isoprene/hex-1-ene copolymerisation followed by e-caprolactone polymerisation, affords trans-Polyisoprene or (trans-Polyisoprene/hex-1-ene copolymer)–poly(e-caprolactone) diblocks of various lengths. The single component initiator is an allylsamarocene compound. An atomic force microscopy study shows that these copolymers are efficient compatibilisers for poly(e-caprolactone) and Polyisoprene blends. Poly(e-caprolactone) chain growth from Sm–Polyisoprene chain.
Marc Visseaux - One of the best experts on this subject based on the ideXlab platform.
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bis phenolate amine supported lanthanide borohydride complexes for styrene and trans 1 4 isoprene co polymerisations
Dalton Transactions, 2015Co-Authors: Fanny Bonnet, Marc Visseaux, Hellen E Dyer, Yassine El Kinani, Chjt Carin Dietz, Pascal Roussel, Marc Bria, Philippe Zinck, Philip MountfordAbstract:New bis(phenolate)amine-supported neodymium borohydride complexes and their previously reported samarium analogues were tested as catalysts for the polymerisation of styrene and isoprene. Reaction of Na2O2NL (L = py, OMe, NMe2) with Nd(BH4)3(THF)3 afforded the borohydride complexes Nd(O2NL)(BH4)(THF) (L = py (1-Nd), OMe (2-Nd), NMe2 (3-Nd)). Complex 1-Nd has shown a propensity to form phenolate-O-bridged dimer [Nd(μ-O2Npy)(BH4)]2 (1′-Nd) as previously observed with the samarium analogues Sm(O2NL)(BH4)(THF) (L = py or Pr). X-ray structures of 1′-Nd and 2-Nd were determined and are presented. The neodymium borohydride complexes 1-Nd to 3-Nd and their samarium analogues Sm(O2NL)(BH4)(THF)x (L = py (1-Sm), OMe (2-Sm), NMe2 (3-Sm), Pr (4-Sm)) were tested as catalysts for the polymerisation of isoprene and styrene in the presence of n-butylethylmagnesium (Mg(nBu)(Et)). All complexes were found to be active for the polymerisation of isoprene in these conditions, leading to Polyisoprene up to 95.1% trans-1,4 stereoregular. They were also found to be active for the polymerisation of styrene leading to atactic polystyrene in all cases. Interestingly, samarium-based complexes were found to be more active than the neodymium ones toward this latter monomer, in sharp contrast to what is usually observed with rare earth borohydride complexes. The structure of both trans-Polyisoprenes and polystyrenes obtained were studied in detail by MALDI-ToF analysis in order to better understand the polymerisation mechanisms. The coordinative chain transfer polymerisation (CCTP) of both monomers was further conducted using Mg(nBu)(Et) as transfer agent. Finally, the statistical copolymerisation of isoprene and styrene was examined using these catalytic systems, leading to the formation of poly[(trans-1,4-isoprene)-co-styrene] with up to 39% of styrene moieties inserted in a highly trans-1,4-stereoregular Polyisoprene.
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highly trans stereospecific isoprene polymerization by neodymium borohydrido catalysts
Macromolecules, 2005Co-Authors: Fanny Bonnet, Marc Visseaux, And Angela Pereira, Denise BarbierbaudryAbstract:Highly stereospecific polymerization of isoprene was achieved using borohydridoneodymium complexes. In combination with stoichiometric amounts of dialkylmagnesium, Nd(BH4)3(THF)3 (1) and Cp*‘Nd(BH4)2(THF)2 (2) (Cp*‘ = C5Me4nPr) afford very efficient catalysts. The activity reaches 37300 (g of Polyisoprene/mol of Nd)/h. Half-lanthanidocene 2 gives rise to Polyisoprene, 98.5% trans-regular, the highest content yet described for a homogeneous organometallic catalyst. NMR experiments argue for the formation of bimetallic Nd(μ-BH4)Mg active species.
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Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts
Macromolecules, 2005Co-Authors: Fanny Bonnet, Marc Visseaux, Angela Pereira, Denise Barbier-baudryAbstract:Highly stereospecific polymerization of isoprene was achieved using borohydrido neodymium complexes. In combination with stoichiometric amounts of dialkylmagnesium, Nd(BH4)3(THF)3 (1) and Cp*'Nd(BH4)2(THF)2 (2) (Cp*' = C5Me4nPr) afford very efficient catalysts. Activity reaches 37300 g Polyisoprene/mol Nd/h. Half-lanthanidocene 2 gives rise to Polyisoprene 98.5 % trans-regular, the highest content yet described for a homogeneous organometallic catalyst. NMR experiments argue for the formation of bimetallic Nd(m-BH4)Mg active species.
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diene polar monomer copolymers compatibilisers for polar non polar polymer blends a controlled block copolymerisation with a single site component samarocene initiator
Macromolecular Chemistry and Physics, 2002Co-Authors: Denise Barbierbaudry, Fanny Bonnet, A Dormond, Eric Finot, Marc VisseauxAbstract:A well-controlled two-step process, the polymerisation of isoprene or isoprene/hex-1-ene copolymerisation followed by e-caprolactone polymerisation, affords trans-Polyisoprene or (trans-Polyisoprene/hex-1-ene copolymer)–poly(e-caprolactone) diblocks of various lengths. The single component initiator is an allylsamarocene compound. An atomic force microscopy study shows that these copolymers are efficient compatibilisers for poly(e-caprolactone) and Polyisoprene blends. Poly(e-caprolactone) chain growth from Sm–Polyisoprene chain.
Frederic Peruch - One of the best experts on this subject based on the ideXlab platform.
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telechelic polybutadienes or Polyisoprenes precursors for recyclable elastomeric networks
Macromolecular Rapid Communications, 2017Co-Authors: Pierre Berto, Stéphane Grelier, Frederic PeruchAbstract:(Bis)furan-telechelic, low-molar-mass polybutadienes and Polyisoprenes are synthesized by controlled degradation of high molar mass polymers and chain-end modifications yielding difunctional, trifunctional, or tetrafunctional polymers. Addition of a bismaleimide to the liquid-modified polymer leads to the formation of a thermoreversible elastomeric network based on the Diels–Alder chemistry for the trifunctional or tetrafunctional polymers, whereas only chain extension occurs for the bifunctional one. Dynamic mechanical analyses or tensile tests are performed on the networks and reveal a similar behavior for Polyisoprene and polybutadiene with nevertheless quite different Young modulus or strain at break. The retro Diels–Alder reaction occurs upon heating, allowing the remolding of the used elastomer. The remolded network exhibits the same mechanical properties as the initial network, showing an efficient material recyclability.
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Bio-inspired cationic polymerization of isoprene and analogues: state-of-the-art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 10(6) g mol(-1), is mainly produced in southeast Asia and represents around 40%-45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions.
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bio inspired cationic polymerization of isoprene and analogues state of the art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 106 g mol−1, is mainly produced in southeast Asia and represents around 40%–45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions. Copyright © 2011 Society of Chemical Industry
Alain Deffieux - One of the best experts on this subject based on the ideXlab platform.
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Bio-inspired cationic polymerization of isoprene and analogues: state-of-the-art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 10(6) g mol(-1), is mainly produced in southeast Asia and represents around 40%-45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions.
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bio inspired cationic polymerization of isoprene and analogues state of the art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 106 g mol−1, is mainly produced in southeast Asia and represents around 40%–45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions. Copyright © 2011 Society of Chemical Industry
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Natural rubber biosynthesis - A living carbocationic polymerization?
Progress in Polymer Science, 2006Co-Authors: Judit E. Puskas, Alain Deffieux, Emilie Gautriaud, Joseph P. KennedyAbstract:An exhaustive in-depth review of the biochemical literature concerning the biosynthesis of Polyisoprenes, including natural rubber (NR, cis-1,4-Polyisoprene cPIP) by rubber-producing plants, and the polymer chemical literature on biomimetic and related syntheses, leads us to postulate that the biosynthesis of polyisoprenoids in general and that of NR in particular, may proceed by a living carbocationic polymerization process. Our analysis led to the formulation of a "Natural Living Carbocationic Polymerization" (NLCP) mechanism in terms of accepted polymer chemical formalism, i.e., initiation, propagation, and equilibria between active and dormant species. A thorough analysis of the intermediates known to be involved in the biosynthesis of NR is consistent with our postulate. (c) 2006 Elsevier Ltd. All rights reserved.
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synthesis characterization and intramolecular end to end ring closure of α isopropylidene 1 1 dihydroxymethyl ω diethylacetal polystyrene block Polyisoprene block copolymers
Macromolecular Chemistry and Physics, 2002Co-Authors: Michel Schappacher, Alain DeffieuxAbstract:Cyclic polystyrene-block-Polyisoprenes of controlled dimensions have been synthesized for the first time by the direct coupling of α-isopropylidene-1,1-dihydroxymethyl-ω-diethylacetal-heterodifunctional linear polystyrene-block-Polyisoprene precursors previously prepared by living anionic polymerization. Cyclization is achieved under high dilution by intramolecular coupling of the polymer ends under acid catalyst conditions. Using this strategy polystyrene-block-Polyisoprene macrocycles of controlled chain dimensions are prepared in high yield (> 90%). Pure cycles were finally recovered by flash chromatography. The synthesis and characterization of both the linear α,ω-heterofunctional polystyrene-block-Polyisoprenes block copolymers precursors and of the corresponding cyclized chain architectures are reported.
Judit E. Puskas - One of the best experts on this subject based on the ideXlab platform.
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Bio-inspired cationic polymerization of isoprene and analogues: state-of-the-art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 10(6) g mol(-1), is mainly produced in southeast Asia and represents around 40%-45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions.
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bio inspired cationic polymerization of isoprene and analogues state of the art
Polymer International, 2012Co-Authors: Samira Ouardad, Sergei V Kostjuk, Alain Deffieux, Marc-elias Bakleh, Francois Ganachaud, Judit E. Puskas, Frederic PeruchAbstract:Natural rubber (NR), which is Polyisoprene about 100% 1,4-cis of high molar mass, > 106 g mol−1, is mainly produced in southeast Asia and represents around 40%–45% of total worldwide elastomer consumption. Whereas more than 2500 plant species are able to produce polyisoprenoids, the only established commercial source of NR is Hevea braziliensis. NR presents high performance properties that are so far not matched by synthetic rubbers. As a consequence, NR is irreplaceable in many applications (aircraft tires, surgery gloves etc.). Nature and synthetic polymer chemists start from different substrates to synthesize Polyisoprenes, i.e. isopentenyl pyrophosphate (IPP), which is a universal building brick utilized by plants and animals, and isoprene monomer, respectively. Nevertheless, we proposed that the elementary processes involved in the biosynthesis of NR are very similar to those of cationic polymerization. In the course of a study on bio-inspired cationic polymerization of isoprene and IPP analogues, it appeared that cationic polymerization of isoprene proceeds readily and leads mainly to its 1,4-trans addition; such a process nevertheless remains difficult to control due to the occurrence of many side reactions (transfer, protic initiation, branching, cyclization). The present paper describes our understanding of the cationic polymerization of isoprene and its analogues catalyzed by different Lewis acids, in solution and aqueous dispersions. Copyright © 2011 Society of Chemical Industry
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Natural rubber biosynthesis - A living carbocationic polymerization?
Progress in Polymer Science, 2006Co-Authors: Judit E. Puskas, Alain Deffieux, Emilie Gautriaud, Joseph P. KennedyAbstract:An exhaustive in-depth review of the biochemical literature concerning the biosynthesis of Polyisoprenes, including natural rubber (NR, cis-1,4-Polyisoprene cPIP) by rubber-producing plants, and the polymer chemical literature on biomimetic and related syntheses, leads us to postulate that the biosynthesis of polyisoprenoids in general and that of NR in particular, may proceed by a living carbocationic polymerization process. Our analysis led to the formulation of a "Natural Living Carbocationic Polymerization" (NLCP) mechanism in terms of accepted polymer chemical formalism, i.e., initiation, propagation, and equilibria between active and dormant species. A thorough analysis of the intermediates known to be involved in the biosynthesis of NR is consistent with our postulate. (c) 2006 Elsevier Ltd. All rights reserved.