PUBLICATIONS and PATENTS
Science Finder - July 2004
53. Reference Type: Journal Article
Author Llauro, M.F., Loiseau, J.,Boisson, F., Ladaviere, C., Claverie, J.
Year: 2004
Title: Unexpected End-Groups of Poly(Acrylic Acid) Prepared by RAFT Polymerization
Journal: J. Pol. Sci., Pol. Chem.
Abstract: Chloroprene was polymerized in emulsion, using a redox system as initiator. With a rosin derivative as surfactant, gel formation was avoided until ca. 70% conversion, but when a reactive maleic hemiester surfactant was used, gel could appear at conversions as low as 5%. The purpose of this paper is to show how this problem of early gel formation can be controlled via the flux of radicals entering the particles. Using more initiator leads to shorter polymer chains, a delayed onset of gel formation and, paradoxically to slower polymerizations Low molecular weight poly(acrylic acid) (PAA) was synthesized by Reversible Addition Fragmentation chain Transfer (RAFT) polymerization using a trithiocarbonate as chain transfer agent (CTA). Using a combination of NMR spectroscopy and MALDI-TOF mass spectrometry, the PAA end-groups of the polymer were analyzed before and after neutralization by sodium hydroxide. The polymer prior neutralization is constituted of the expected trithiocarbonate chain-ends and of the H-terminated chains issued from a reaction of transfer to solvent. After neutralization, the trithiocarbonates are transformed into thiols, disulfides, thiolactones, and additional H-terminated chains. By quantifying the different end-groups, it was possible to demonstrate that fragmentation is the rate limiting step in the transfer reaction.
Volume: ASAP
Notes: written in English.
52. Reference Type: Journal Article
Author Thenoz, F., Claverie*, J., Graillat, C. , Guyot, A. Sauterey, F.
Year: 2004
Title: Emulsion Polymerization of Chloroprene in the Presence of a Maleic Polymerizable Surfactant: Control of Gel Formation at Low Conversion.
Journal: Macromolecules
Abstract: Chloroprene was polymerized in emulsion, using a redox system as initiator. With a rosin derivative as surfactant, gel formation was avoided until ca. 70% conversion, but when a reactive maleic hemiester surfactant was used, gel could appear at conversions as low as 5%. The purpose of this paper is to show how this problem of early gel formation can be controlled via the flux of radicals entering the particles. Using more initiator leads to shorter polymer chains, a delayed onset of gel formation and, paradoxically to slower polymerizations.
Volume: 37
Issue: 11
Pages: 4081-4086
Notes: written in English.
51. Reference Type: Journal Article
Author Uzulina, I, Gaillard N., Guyot A., Claverie J.
Year: 2003
Title: Controlled Radical Polymerization of Styrene in Miniemulsion Polymerization Using Reversible Addition Fragmentation Chain Transfer
Journal: C. R. Acad. Sci
Abstract: Miniemulsion polymerizations of styrene in the presence of two reversible addition-fragmentation chain-transfer (RAFT) agents were studied. The rates were significantly retarded by the presence of a RAFT agents S-(thiobenzoyl)thioglycolic acid, 1, or dithiobenzoic acid 1-phenylethyl ester, 2. Control in miniemulsion polymerization is not as good as for bulk polymerizations. The miniemulsions could also be stabilized against Ostwald ripening by a polymer terminated by a dithiobenzoic moiety. In this case, the polymerization was not controlled because of the generation of renucleated particles.
Notes: written in English.
Volume: 6
Issue: 11-12
Pages: 1375-1384
Notes: written in English.
50. Reference Type: Book Section
Author: Soula, R.; Claverie, J.; Spitz, R.; Guyot, A.
Year: 2003
Title: Catalytic polymerization of olefins in emulsion: a breakthrough in polymer colloids.
Book: Surfactant Science Series (2003),
Volume: 115
Issue: 9
Pages: 77-92
Notes: written in English.
49. Reference Type: Book Section
Author: Mecking, S.; Claverie, J.
Year: 2003
Title: Metal-Mediated Aqueous Polymerization
Editor: Rieger, B.; Baugh, L. Saunders; Kacker, S.; Striegler, S.
Book Title: Late Transition Metal Polymerization Catalysis
City: Frankfurt
Publisher: VCH
Pages: 231-278
Notes: written in English
48. Reference Type: Journal Article
Author: Loiseau, J.; Doeerr, N.; Suau, J. M.; Egraz, J. B.; Llauro, M. F.; Ladaviere, C.; Claverie, J.
Year: 2003
Title: Synthesis and Characterization of Poly(acrylic acid) Produced by RAFT Polymerization. Application as a Very Efficient Dispersant of CaCO3, Kaolin, and TiO2
Journal: Macromolecules
Volume: 36
Issue: 9
Pages: 3066-3077
Abstract: Poly(acrylic acid), PAA, was prepd. by controlled radical polymn. with reversible addn.-fragmentation chain transfer. Using trithiocarbonic acid dibenzyl ester and trithiocarbonic acid bis(1-phenylethyl) ester as chain transfer agents (CTA), the polymn. is controlled for low ratios [AA]:[CTA]. At higher ratios, the polymn. is plagued by transfer to solvent. Transfer to polymer is also detected at high conversion, as shown by the presence of branches in NMR spectroscopy. In its neutralized form, PAA chains are not all terminated by a thiol end group, as shown by elemental anal., thiol titrn., and MALDI TOF MS. Finally, dispersion of CaCO3, kaolin, and TiO2 using these PAA reveals that the dispersion characteristics are significantly improved using low-polydispersity PAA.
Notes: written in English.
47. Reference Type: Journal Article
Author: Gaillard, Nicolas; Guyot, Alain; Claverie, Jerome
Year: 2003
Title: Block copolymers of acrylic acid and butyl acrylate prepared by reversible addition-fragmentation chain transfer polymerization: synthesis, characterization, and use in emulsion polymerization
Journal: Journal of Polymer Science, Part A: Polymer Chemistry
Volume: 41
Issue: 5
Pages: 684-698
Abstract: Amphiphilic block copolymers of poly(acrylic acid-b-Bu acrylate) (I) were prepd. by reversible addn.-fragmentation chain transfer polymn. in a one-pot reaction. I were characterized by NMR, static and dynamic light scattering, tensiometry, and size exclusion chromatog. The aggregation characteristics of I corresponded to those theor. predicted for a star micelle. In a Bu acrylate-Me methacrylate emulsion copolymn., low amts. of I could stabilize the latexes with solid contents up to 50%.
Notes: written in English.
46. Reference Type: Journal Article
Author: Claverie, Jerome P.; Soula, Remi
Year: 2003
Title: Catalytic polymerizations in aqueous medium
Journal: Progress in Polymer Science
Volume: 28
Issue: 4
Pages: 619-662
Abstract: A review. A large variety of polymers is synthesized by catalysis with organometallic complexes. The polymns. are usually performed under anhyd. reaction conditions due to the poisoning effect of water toward the metal center. Nevertheless, recent advances have demonstrated that water can be a suitable diluent (or solvent) for these polymns. Therefore, this review covers the aq. ring opening metathesis polymn., alkyne polymn., .alpha.-olefin polymn., alternated ethylene/CO copolymn. and diene polymn., catalyzed by transition metal complexes. The recent advances in the aforementioned polymns. are presented in terms of catalyst synthesis, catalytic activity and polymer characteristics. Unprecedented materials (nanometric dispersions of polymer in water, i.e. latex) or polymn. processes (polymn. in the presence of surfactant) are also described.
Notes written in English.
45. Reference Type: Journal Article
Author: Uzulina, Ivetta; Zicmanis, Andris; Graillat, Christian; Claverie, Jerome; Guyot, Alain
Year: 2002
Title: Nonionic maleic surfmers
Journal: Journal of Dispersion Science and Technology
Volume: 23
Issue: 6
Pages: 799-808
Abstract: A set of nonionic maleic surfactants have been prepd., all coming from the derivatization of maleic hemiesters with a long alkyl chain. They are either amidoesters or diester products. In the case of amidoesters, the acid group was first activated and then reacted with primary or secondary or tertiary ethanolamine compds. In the case of diesters, the hemiester, was reacted directly with glycidol, in acid or basic conditions. These surfactants were characterized for their structure by 1H NMR, and for their surface active properties, by surface tension measurements. They were also used in batch emulsion polymn. of styrene, and seeded core-shell copolymn. of a 1/1 mixt. of styrene and butylacrylate in a semi-continuous process. In both cases, stable latexes with high monomer conversion, and limited amts. of floc were produced, with about the targeted particle size. It was shown that these reactive surfactants are incorporated with high yields, and they are not extd. with acetone or ethanol. However, these latexes do not display the expected steric stabilization obsd. with other usual nonionic surfactants.
Notes: written in English.
44. Reference Type: Patent
Author: Suau, Jean-Marc; Egraz, Jean-Bernard; Claverie, Jerome; Ladaviere, Catherine
Year: 2002
Title: Method for controlled free radical polymerization of acrylic acid and salts thereof, resulting low-polydispersity polymers, and their uses
Country: Application: world patent
Assignee: (Coatex S.A.S., Fr.).
Pages: 107 pp
Date: 20020228.
Number: 2002-FR7220270571
Abstract: Polymers of acrylic acid or its salts having polydispersity <2 and gel content at conversion >90% are manufd. by free-radical polymn. in the presence of RXC(S)SR' (X = O or S, R = a group causing stabilization of RX function by CX, R' = a group such that the R'S bond is a CS bond) as chain-transfer agents. A typical chain-transfer agent was manuf. by reaction of 8.8 g K O-ethyldithiocarbonate 20 min at 15.degree. with di-Et 2-bromo-2-methylmalonate in water in the presence of Aliquat 336.
Notes:written in French.
43. Reference Type: Journal Article
Author: Stoffelbach, Francois; Claverie, Jerome; Poli, Rinaldo
Year: 2002
Title: Atom transfer radical polymerization of styrene controlled by phosphine-containing coordination compounds of Mo(III)/Mo(IV)
Journal: Proceedings of the Academy of Science
Volume: 5
Issue: 1
Pages: 37-42
Abstract: Controlled polymn. of styrene was achieved under ATRP conditions using a trimethylphosphine-contg. MoIII/MoIV catalyst system. Linearity of the Mn vs. conversion and low PDI were obsd. in bulk, in a 30% (vol./vol.) PhCl soln., and in a chain extension expt. when using MoCl3(PMe3)3/BIB (ethyl-2-bromoisobutyrate). Controlled polymn. was also obsd. in a reverse ATRP expt. starting from MoCl4(PMe3)3/AIBN. The absence of chain transfer and termination was confirmed by NMR and MALDI-TOF data of polymers obtained using BEB ((1-bromoethyl)benzene) and BIB as initiators.
Notes: written in English.
42. Reference Type: Journal Article
Author: Soula, R.; Saillard, B.; Spitz, R.; Claverie, J.; Llaurro, M. F.; Monnet, C.
Year: 2002
Title: Catalytic Copolymerization of Ethylene and Polar and Nonpolar .alpha.-Olefins in Emulsion
Journal: Macromolecules
Volume: 35
Issue: 5
Pages: 1513-1523
Abstract: Novel P,O-chelated Ni(II) catalysts for ethylene and .alpha.-olefins polymn. have been used for the copolymn. of ethylene with various long-chain .alpha.-olefins in emulsion. Nonfunctionalized .alpha.-olefins have been copolymd. with ethylene using miniemulsion to disperse the catalyst at the nanometric level. The influence of the comonomer on catalyst performances as well as latex properties has been analyzed. High comonomer incorporation and stable latex of 30% solid content can be achieved by this method. Other comonomers such as .alpha.,.omega.-dienes, .alpha.-olefins bearing a polar functionality in the .omega.-position, and styrene have also been copolymd. in emulsion. Polymers and latexes have been characterized by an array of techniques including 13C NMR, TEM, DSC, and GPC. It is shown that this emulsion process is specially adapted for copolymn. of ethylene with polar olefins.
Notes:written in English.
41. Reference Type: Journal Article
Record Number: 11
Author: Soula, Olivier; Muchnik, Anna; Bloy, Christian; Meyrueix, Remi; Claverie, Jerome P.; Soula, Gerard
Year: 2002
Title: Relaxin delivery using polyaminoacid nanoparticles
Journal: Abstracts of Papers, 223rd ACS National Meeting, Orlando, FL, United States, April 7-11, 2002
Pages: COLL-412
Abstract: Relaxin is 6.0 kD protein that is has potential benefits for the treatment of several diseases, such as scleroderma, peripheral arterial disease and congestive heart failure. We have developed a sustained release dosage form of Relaxin using nanoparticles made of block copolymers of leucine and sodium glutamate. Relaxin adsorbs onto these nanoparticles in order to minimize hydrophobic contacts with water. The adsorption is very strong (no desorption with diln.) and adsorption kinetics are rapid, but the adsorbed protein can be displaced by exchange with another protein. Expts. to compare desorption energy of relaxin from Medusa nanoparticles with other proteins (insulin, human growth hormone, e.g.) are presented. Nanoparticle synthesis, characterization, protein adsorption and in vivo results will be described. The protein adsorption has also been monitored by isothermal titrn. calorimetry.
Notes:written in English.
40. Reference Type: Journal Article
Author: Schneider, M.; Claverie, J.; Graillat, C.; McKenna, T. F.
Year: 2002
Title: High solids content emulsions. I. A study of the influence of the particle size distribution and polymer concentration on viscosity
Journal: Journal of Applied Polymer Science
Volume: 84
Issue: 10
Pages: 1878-1896
Abstract: An exptl. and modeling study was carried out to understand the relationship between the viscosity of a multimodal latex and its particle-size distribution (PSD) and polymer concn. This study illustrates the inadequacy of existing models in predicting the viscosity of complex latices. It is shown that the latex viscosity at a fixed shear rate is very sensitive to the polymer concn. at high solids content and to the PSD.
Notes: written in English.
39. Reference Type: Journal Article
Author: Meyrueix, Remi; Constancis, Alain; Claverie, Jerome P.; Soula, Olivier; Soula, Gerard
Year: 2002
Title: Concentrated colloidal suspensions of polyamino-based nanoparticles
Journal: Abstracts of Papers, 223rd ACS National Meeting, Orlando, FL, United States, April 7-11, 2002
Pages: COLL-014
Abstract: Nanoparticles of amphiphilic block copolymer of poly(L-leucine-block-sodium glutamate) self assembles into water to form stable colloidal suspension. Characterization in dil. regime (DLS, SAXS, RMN, CD, time resolved fluorescence spectroscopy) reveals that the nanoparticles contain an hydrophobic leucine core partially organized in alpha helixes and surrounded by a polyelectrolyte brush of polyglutamate chains. The extent of the polyelectrolyte chains in water has been measured as a function of pH and ionic strength. The rheol. of the concd. suspensions is sharply dependent upon the thermal history of the prepn. as well as upon the ionic strength of the soln. An attempt is made to relate this macroscopic behavior to the structure of the concd. suspension studied by light scattering and SAXS. An interpretation is proposed to explain some unusual results such as the well marked peak of the low shear viscosity obsd. when the concn. is increased at low ionic strength.
Notes: written in English.
38. Reference Type: Journal Article
Author: Lecomte, Jean-Pierre; Meyrueix, Remi; Soula, Olivier; Bloy, Christian; Claverie, Jerome P.; Soula, Gerard
Year: 2002
Title: Adsoprtion and desorption of Interferon onto colloidal hydrophobic surfaces
Journal: Abstracts of Papers, 223rd ACS National Meeting, Orlando, FL, United States, April 7-11, 2002
Pages: COLL-413
Abstract: Interferon-a is a therapeutic protein used in the treatment of hepatithis C and cancer. We have designed nanoparticles (size ranging 10-30 nm) contg. hydrophobic patches colloidaly stabilized by polyelectrolyte corona. In water, interferon spontaneously adsorbs onto these nanoparticles by hydrophobic interactions. This adsoprtion mechanism has been studied using a vast array of techniques such as time resolved fluorescence spectroscopy, isothermal titrn. calorimetry and chromatog. techniques. Adsorbed interferon can be displaced from the surface by other proteins and by suitable surfactants. The kinetics of desorption have been studied and compared with in vivo desorption of the protein-nanoparticle complex in rats and dogs.
Notes: written in English.
37. Reference Type: Journal Article
Author: Claverie, Jerome P.; Meyrueix, Remi; Soula, Olivier; Bloy, Christian; Soula, Gerard
Year: 2002
Title: Self assembled nanoparticles for protein delivery
Journal: Abstracts of Papers, 223rd ACS National Meeting, Orlando, FL, United States, April 7-11, 2002
Pages: COLL-043
Abstract: Copolyaminoacids of leucine and sodium glutamate spontaneously form nanoparticles into water (size comprised between 10-100 nm). These nanoparticles have been studied and characterized by a wide array of techniques (NMR, CD, IR, Raman, RX, AFM, TEM, SAXS and fluorescence spectroscopy). Proteins adsorb onto the surface of these nanoparticles, and more precisely onto polyleucine patches, via hydrophobic interactions. The nanoparticles/protein complexes can then be used for the controlled release of therapeutic proteins in vivo. The presentation will focus on : - the characterization of the nanoparticles made of block and gradient type copolymers - the description of the nanoparticle/protein complexes for two proteins : relaxin and interferon. This topic will esp. cover the adsorption/desorption kinetics with these colloidal systems and the characterization of the adsorbed protein - in vivo results for injections in humans and in several animals. The relationship between nanoparticle structure and in vivo release time.
Notes: written in English.
36. Reference Type: Patent
Author: Claverie, Jerome; Soula, Remi; Spitz, Roger
Year: 2002
Title: Olefin polymerization catalyst
Country: Application: World patent
Assignee: (Atofina, Fr.).
Pages: 43 pp
Date: 20010917.
Number: 2001-FR2881 0224763
Abstract: The invention concerns a catalyst of formula: I, wherein: E is an oxygen or sulfur atom; X is a phosphorus, arsenic or antimony atom; M is a nickel, palladium or platinum atom comprising a non-attributed valency; a is 1 or 2; R1, R2, R3, identical or different can be selected among hydrogen, alkyl, cycloalkyl, aryl, alkylaryl, arylalkyl radicals, the hydroxyl radical, the alkoxide radicals (with 1 to 20 carbon atoms), the groups C(O)OR', SO3Y; R' represents a hydrocarbon radical comprising 1 to 15 carbon atoms, Y represents Li, Na, K, NH4+, or NR''4+; R'' represents hydrocarbon radical comprising 1-15 carbon atoms; and Z represents a hydrocarbon radical comprising 2 to 3 carbon atoms; R represents a hydrocarbon radical of valency a, provided that at least one of the radicals Z or R bears at least an electroattractive substituent; prepd. in-situ for olefin polymn. in a polar medium. A typical ligand was manufd. by reaction of ethoxycarbonylmethyltriphenylphosphonium bromide with heptafluorobutyryl chloride.
Notes: written in French.
20020328
35. Reference Type: Journal Article
Author: Uzulina, Ivetta; Zicmanis, Andris; Graillat, Christian; Claverie, Jerome; Guyot, Alain
Year: 2001
Title: Synthesis of polymer colloids using polymerizable surfactants
Journal: Macromolecular Chemistry and Physics
Volume: 202
Issue: 16
Pages: 3126-3135
Abstract: A series of new anionic surfactants were prepd. by reacting a polymerizable alc. with either maleic or succinic anhydride, as well as sulfosuccinic anhydride, resulting in either bireactive or mono-reactive surfactants, either carboxylated or sulfonated. The synthesis presented and the crit. micelle concn. (CMC) detd. These compds. were engaged in the emulsion polymn. of styrene in batch and also in semi-batch seeded copolymn. producing core-shell latexes. The core was a polystyrene seed prepd. using sodium dodecyl sulfate (SDS), thoroughly purified through ion exchange resins. The seed was then swollen overnight with a small amt. of a 1: 1 mixt. of styrene and Bu acrylate, and finally fed with the same mixt. together with the reactive surfactant. The amt. of monomer was calcd. so that, from a seed with a diam. of 100 nm, a core-shell latex of 150 nm was obtained. The amt. of surfactant was such that a coverage of 80% was aimed for. The calcd. solid content was 9%. Using 3.5 wt.-% of surfactant (vs. monomer), the conversion reached about 90%, the floc being limited most often to less than 2%. The target diam. of the core-shell latex was nearly obtained. The latexes were stable only with limited amts. of added electrolytes and failed the test of freeze-thawing. About 40-50% of the surfactant were located on the surface.
Notes: written in English.
34. Reference Type: Journal Article
Author: Soula, R.; Novat, C.; Tomov, A.; Spitz, R.; Claverie, J.; Drujon, X.; Malinge, J.; Saudemont, T.
Year: 2001
Title: Catalytic Polymerization of Ethylene in Emulsion
Journal: Macromolecules
Volume: 34
Issue: 7
Pages: 2022-2026
Abstract: Ethylene polymn. catalyzed by nickel(II) keto-ylide complexes has been performed in water to yield a latex of linear PE. Colloidal stability is highly enhanced by the use of a miniemulsion technique to disperse the catalyst prior contact with the monomer. Latex of typically 200 nm particle diams. and up to 10% solids are generated by this method. The influence of several factors (temp., pressure, solids) onto the polymn. is studied in detail. The surfactant adsorption isotherms onto these highly cryst. and nonpolar particles are also presented.
Notes:written in English.
33. Reference Type: Journal Article
Author: Soula, R.; Broyer, J. P.; Llauro, M. F.; Tomov, A.; Spitz, R.; Claverie, J.; Drujon, X.; Malinge, J.; Saudemont, T.
Year: 2001
Title: Very Active Neutral P,O-Chelated Nickel Catalysts for Ethylene Polymerization
Journal: Macromolecules
Volume: 34
Issue: 8
Pages: 2438-2442
Abstract: A series of highly active Ni-based neutral catalysts for ethylene polymn. is presented. These catalysts are obtained by direct complexation of simple fluorinated keto-ylides onto bis(1,5-cyclooctadiene)nickel. Catalyst formation readily occurs in the presence of an olefin, but due to the electron deficiency of the ligand, it hardly happens in the absence of an olefin or another Lewis base. Activities greater than 2 .times. 106 (gPE/gNi)/h and productivities higher than 15 .times. 106 gPE/molNi are typically obsd. These catalysts are also active for the polymn. of .alpha.-olefins such as 1-hexene and 1-propene. Polymer characterization indicates that highly linear, low mol. wt. PEHD is formed by these complexes.
Notes:written in English.
32. Reference Type: Journal Article
Author: Le Grognec, Erwan; Claverie, Jerome; Poli, Rinaldo
Year: 2001
Title: Radical Polymerization of Styrene Controlled by Half-Sandwich Mo(III)/Mo(IV) Couples: All Basic Mechanisms Are Possible
Journal: Journal of the American Chemical Society
Volume: 123
Issue: 39
Pages: 9513-9524
Abstract: D. functional calcns. of bond dissocn. energies (BDEs) have been used as a guide to the choice of metal system suitable for controlling styrene polymn. by either the stable free radical polymn. (SFRP) or the atom transfer radical polymn. (ATRP) mechanism. In accord with the theor. prediction, CpMo(.eta.4-C4H6)(CH2SiMe3)2, (I), is not capable of yielding SFRP of styrene. Still in accord with theor. prediction, CpMo(.eta.4-C4H6)Cl2, (II), CpMo(PMe3)2Cl2, (III), and CpMo(dppe)Cl2 (dppe = 1,2-bis(diphenylphosphino)ethane), (IV), yield controlled styrene polymn. by the SFRP mechanism in the presence of 2,2'-azobisisobutyronitrile (AIBN). This arises from the generation of a putative Mo(IV) alkyl species from the AIBN-generated radical addn. to the Mo(III) compd. The controlled nature of the polymns. is indicated by linear Mn progression with the conversion in all cases and moderate polydispersity indexes (PDIs). Controlled polymn. of styrene is also given by compds. III and IV in combination with alkyl bromides. These complexes then operate by the ATRP mechanism, again in accord with the theor. predictions. Controlled character is revealed by linear increase of Mn vs. conversion, low PDIs, a stop-and-go expt., and 1H NMR and MALDI-TOF analyses of the polymer end groups. The same controlled polymn. is given by a /"reverse/" ATRP expt., starting from AIBN and CpMo(PMe3)2Cl2Br. On the other hand, when compd. II or I is used in combination with an alkyl bromide (as for an ATRP expt.), the isolated polystyrene shows by Mn, 1H NMR, and MALDI-TOF analyses that catalytic chain transfer (CCT) radical polymn. takes place in this case. Kinetics simulations underscore the conditions regulating the radical polymn. mechanism and the living character of the polymn. The complexes herein described are ineffective at controlling the polymn. of Me methacrylate.
Notes written in English.
31. Reference Type: Journal Article
Author: Ladaviere, Catherine; Doerr, Nicole; Claverie, Jerome P.
Year: 2001
Title: Controlled Radical Polymerization of Acrylic Acid in Protic Media
Journal: Macromolecules
Volume: 34
Issue: 16
Pages: 5370-5372
Abstract: Various dithio esters were prepd. and screened for their suitability as chain transfer agents in the title polymn.
Notes: written in English.
30. Reference Type: Journal Article
Author: Claverie, Jerome P.; Viala, Sophie; Maurel, Vincent; Novat, Christian
Year: 2001
Title: Ring-Opening Metathesis Polymerization in Emulsion
Journal: Macromolecules
Volume: 34
Issue: 3
Pages: 382-388
Abstract: Ring-opening metathesis polymn. (ROMP) of norbornene (NBE), catalyzed by water-sol. ruthenium alkylidenes 1, RuCl2(PCy2(C5H10NMe2Cl))2(:CHPh), or 2, RuCl2(TPPTS)2(:CHCO2Et) (TPPTS = tris(3-sulfonatophenyl)phosphine, sodium salt), has been carried out in emulsion. Polynorbornene latexes (PNBE) can be obtained in high yields, in the absence of floc, and with high solids, if Dowfax is used as surfactant. The nucleation mechanism of the polymn. has been found to be a continuous homogeneous nucleation. The resulting polymer particles are formed of aggregates of small primary particles, stabilized by the highly ionized chain ends. Typical particle sizes are ranging from 50 to 100 nm, even at higher solids. Less strained olefins, such as cyclooctene, COE, and 1,5-cyclooctadiene, COD, cannot be efficiently polymd. by catalysts 1 or 2; Nevertheless, these monomers are polymd. by a hydrophobic catalyst, 3, RuCl2(PCy3)2(:CHPh). To form colloidal objects, the catalyst is dispersed into water through the use of a miniemulsion technique. The miniemulsion is then fed with monomer, and after polymn., a latex is obtained. Monomer conversion is moderate, but a latex is generated in the absence of floc.
Notes: written in English.
29. Reference Type: Journal Article
Author: Claverie, Jerome P.; Spitz, Roger; Drujon, Xavier; Touchard, Virginie; Llauro, Marie France; Soula, Remi
Year: 2001
Title: Catalytic polymerization of olefins in emulsion
Journal: Abstracts of Papers - American Chemical Society
Volume: 221st
Pages: PMSE-187
Abstract: Alpha-olefin (co)polymn. catalyzed by nickel(II) keto-ylide complexes has been performed in water to yield a latex of HDPE and of LLDPE. Colloidal stability is highly enhanced by the use of a miniemulsion technique to disperse the catalyst prior contact with the monomer. Latex of typically 200 nm particle diam. is generated by this method. The influence of several factors (temp., pressure, solids, catalyst) onto the polymn. is studied into details. HDPE lattices are formed of irregular cryst. particles that exhibit a moderate colloidal stability, whereas LLDPE lattices are stable, and can be generated in high solids. The resulting nanoparticles have film forming properties that will be presented.
Notes: written in English.
28. Reference Type: Journal Article
Author: Claverie, J.; Spitz, R.; Drujon, X.; Touchard, V.; Llauro, M. F.
Year: 2001
Title: Catalytic polymerization of olefins in emulsion
Journal: Polymeric Materials Science and Engineering
Volume: 84
Pages: 329-330
Abstract: Alpha-olefin (co)polymn. catalyzed by nickel(II) keto-ylide complexes has been performed in water to yield a latex of HDPE and of LLDPE. Colloidal stability is highly enhanced by the use of a miniemulsion technique to disperse the catalyst prior contact with the monomer. Latex of typically 200 nm particle diam. is generated by this method. The influence of several factors (temp., pressure, solids, catalyst) onto the polymn. is studied into details. HDPE lattices are formed of irregular cryst. particles that exhibit a moderate colloidal stability, whereas LLDPE lattices are stable, and can be generated in high solids. The resulting nanoparticles have film forming properties that will be presented.
Notes: written in English.
27. Reference Type: Journal Article
Author: Uzulina, I.; Kanagasabapathy, S.; Claverie, J.
Year: 2000
Title: Reversible addition fragmentation transfer (RAFT) polymerization in emulsion
Journal: Macromolecular Symposia
Volume: 150
Issue: Polymers in Dispersed Media
Pages: 33-38
Abstract: RAFT polymn. of styrene, Me methacrylate (MMA) and vinyl acetate has been effected in emulsion polymn. A com. chain transfer agent, 1, was used for starting the reversible transfer reaction. Usually, low chain transfer consts. were found with this compd., but transfer could be improved by generating in situ a suitable chain transfer agent. Controlled behavior was then obsd. under emulsion conditions.
Notes: written in English.
26. Reference Type: Journal Article
Author: Le Grognec, Erwan; Poli, Rinaldo; Richard, Philippe; Claverie, Jerome
Year: 2000
Title: Application of 17-electron organomolybdenum compounds to polymerization catalysis
Journal: Abstracts of Papers - American Chemical Society
Volume: 220th
Pages: INOR-331
Accession Number: AN 2000:795776
Abstract: Half-sandwich Mo(II), Mo(III), and Mo(IV) complexes may be related by atom transfer processes. Previous studies had shown Cl uptake processes from chlorinated solvents by Mo(II) and by Mo(III) species, as well as the thermal instability for alkyl-contg. Mo(III) complexes toward loss of Me radicals. The thermally unstable CpMo(CH3)2(PMe3)2 complex has now been isolated at low temp. and its phys. properties have been detd. Several thermally more stable diene-contg. alkyl derivs. of Mo(III), CpMo(.eta.4-diene)R2 and Cp* analogs, have also been isolated and fully characterized. The application of these complexes in both Ziegler-Natta and radical-type olefin polymn. processes will be outlined.
Notes: written in English.
25. Reference Type: Journal Article
Author: Claverie, Jerome P.; Viala, Sophie; Novat, Christian; Kanagasabapathy, Subbarrediar
Year: 2000
Title: Ring opening metathesis polymerization in emulsion
Journal: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry)
Volume: 41
Issue: 1
Pages: 422-423
Abstract: We have used Grubbs type water-sol. catalysts in an emulsion polymn. to generate novel polymer colloids. In all cases, the resulting latex with particle sizes ranging from 20 nm to 500 nm is obtained without floc formation, even at 50% solids. Functionalization of the nanoparticle is easily effected by chain transfer with a suitable olefin. The mechanism of the polymn. seems to involve a homogeneous nucleation step, even when the surfactant is in concn. higher than crit. micelle concn. Rapidly, a const. no. of active sites per particle is obsd. In terms of catalytic activity, notable differences could be detected between different class of ruthenium-based catalysts. Finally, a miniemulsion polymn. process was devised, allowing the synthesis of ROMP based nanoparticles of polycyclooctene and 1,4-polybutadiene.
Notes:written in English.
24. Reference Type: Journal Article
Record Number: 26
Author: Claverie, Jerome P.; Viala, Sophie; Novat, Christian; Kanagasabapathy, Subbareddiar
Year: 2000
Title: Ring-opening metathesis polymerization in emulsion
Journal: Book of Abstracts, 219th ACS National Meeting, San Francisco, CA, March 26-30, 2000
Pages: POLY-292
Abstract: The development of water-sol. catalysts for ring-opening metathesis polymn. has chiefly permitted the elaboration of polymers based on water-sol. monomers. Here, we have used Grubbs type water sol. catalysts in an emulsion polymn. to generate novel polymer colloids. In all cases, the resulting latex with particle sizes ranging from 20 nm to 500 nm is obtained without floc formation, even at 50% solids. Functionalization of the nanoparticle is easily effected by chain transfer with a suitable olefin. The mechanism of the polymn. seems to involve a homogeneous nucleation step, even when the surfactant is in concn. higher than cmc. Rapidly, a const. no. of active sites per particle is obsd. In terms of catalytic activity, notable differences could be detected between different class of ruthenium based catalysts. Finally, a miniemulsion polymn. process has been devised, allowing the synthesis of ROMP based nanoparticles of polycyclooctene and 1,4-polybutadiene.
Notes: written in English.
23. Reference Type: Book
Editors: Claverie, Jerome; Charreyre, Marie-Therese; Pichot, Christian; Editors
Year: 2000
Title: Proceedings of the fourth International Symposium on Polymers in Dispersed Media, held 11-15 April 1999, in Lyon, France. [In: Macromol. Symp., 2000; 150]
Number of Pages: 324 pp
Notes: written in English
22. Reference Type: Book
Editors: Claverie, Jerome; Charreyre, Marie-Therese; Pichot, Christian; Editors
Year: 2000
Title: Proceedings of an International Conference on Polymers in Dispersed Media, held 11-15 April 1999. [In: Macromol. Symp., 2000; 151]
Number of Pages: 321 pp
Notes: written in English.
21. Reference Type: Patent
Record Number: 23
Author: Christie, David Innes; Claverie, Jerome; Kanagasabapathy, Saba
Year: 2000
Title: Radical-initiated aqueous emulsion polymerization
Country: Application: German Patent 99-19914953
DE
Assignee: (BASF A.-G., Germany).
Pages: 20 pp
Date: 19990401.
Abstract: Ethylenically unsatd. monomers are polymd. in aq. emulsion by means of a radical polymn. initiator in the presence of (as regulator) a metal complex which is more sol. in an aq. medium than in styrene. Thus, 110 g H2O contg. 0.5 g Na dodecyl sulfate, 0.2 g Na2CO3, and 44 mg o-C6H4[N:CHC6H3(OH)2-2,4]2 at 20.degree./1 bar abs. was mixed first with an aq. soln. of 36 mg Co(OAc)2.4H2O and then with 10.3 g styrene contg. 180 mg HCI3 to give an emulsion, which was heated to 90.degree. in 11 min. After 330 min at 90.degree. the styrene conversion was 36.8% and the polystyrene formed showed no.-av. mol. wt. 2300, polydispersity 2.7 and av. particle diam. 618 nm.
Notes: written in German.
20. Reference Type: Journal Article
Author: Kanagasabapathy, S.; Claverie, J.; Uzulina, I.
Year: 1999
Title: Synthesis of well-defined triblock copolymer by reversible addition-fragmentation chain transfer polymerization in emulsion
Journal: Book of Abstracts, 218th ACS National Meeting, New Orleans, Aug. 22-26
Pages: POLY-422
Abstract: Emulsion polymn. of styrene using S-thiobenzoyl-thioglycolic acid (I) as a chain transfer agent in RAFT was carried out at 95oC. The linear increase in mol. wt. with conversion and time confirms the simultaneous growth of the propagating radicals. Triblock copolymer of ABC type (styrene-b-butylacrylate-b-acrylic acid) can be successfully prepd. using I by RAFT process. Miniemulsion polymn. of styrene in the presence of I lead to controlled mol. wt. polymer latex with polydispersity of 1.6.
Notes: written in English.
19. Reference Type: Journal Article
Author: Kanagasabapathy, S.; Claverie, J.; Uzulina, I.
Year: 1999
Title: Synthesis of well defined triblock copolymer by reversible addition fragmentation chain transfer (RAFT) polymerization in emulsion
Journal: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry)
Volume: 40
Issue: 2
Pages: 1080-1081
Abstract: Controlled emulsion polymn. of styrene using PhCS2CH2CO2H (I) as a chain-transfer agent via the RAFT process gave narrow-polydispersity polystyrene latexes with high conversion and low coagulation. Triblock copolymers with Bu acrylate and acrylic acid were then prepd. in emulsion using I.
Notes: written in English.
18. Reference Type: Patent
Record Number: 29
Author: Christie, David; Claverie, Jerome; Kanagasabapathy, Saba
Year: 1999
Title: Method for radically initiated polymerization
Country: Application: German Patent DE99-19920553
Assignee: (BASF A.-G., Germany).
Pages: 14 pp
Date: 19990505.
Abstract: Ethylenically unsatd. monomers are polymd. in a liq. medium by use of a radical initiator in the presence of an organometallic compd. I [L = Lewis base; M = metal ion; R1-R4 = H, CO2M1, PO3HM1, PO3M3M4, (un)substituted C1-12 alkyl, CH2O(CH2CH2O)mM2; M1 = H, alkali metal, ammonium, (CH2CH2O)mM2; M2 = H, alkali metal, ammonium; M3, M4 = alkali metal, ammonium; R5-R8 = H, F, Cl, Br, I, NO2, CHO, SM1, OM1, CO2M1, CN, etc.; Y = direct link, (un)substituted bridging group of 1-3 member atoms; m = 1-1000; p = 0-2]. In polymn. of styrene under Ar in the dark at 90.degree. in the presence of PhCHBrMe and I (M = Co2+, R1-R8 = H, Y = direct link, p = 0) and a small amt. of PhCl, the Mn was approx. proportional to styrene conversion, and reached 3500 (Mw/Mn = 1.4) at 84.2% conversion after 4400 min. The I can also be formed in situ from a suitable dihydroxy diimine and a metal salt, e.g., Co(OAc)2.
Notes:written in German.
17. Reference Type: Journal Article
Author: Marestin, Catherine; Guyot, Alain; Claverie, Jerome
Year: 1998
Title: Direct Measurement of Oligomers Entry Rate onto Latex Particles in an Emulsion Polymerization
Journal: Macromolecules
Volume: 31
Issue: 5
Pages: 1686-1689
Abstract: The coeff. of entry of Me methacrylate (MMA) aq. oligomers into polymer particles was measured by direct EPR expts. A stable spin trap (nitroxide free radical) was covalently grafted on the surface of a monodisperse latex. This seed has then been involved in a MMA emulsion polymn. The trapping has been monitored by the decay of EPR signal. From the kinetics of entry, we have deduced a coeff. of entry comprised between 1 and 2 s-1 for two different initiators. Entrant oligomers have been collected after cleavage of the thermoreversible C-O bound. GPC and IR spectroscopy successfully have allowed to det. the nature of these oligomers. This method has enabled to measure the crit. size z (z = 5) of MMA oligomers before entering a particle.
Notes: written in English.
16. Reference Type: Journal Article
Record Number: 33
Author: Marestin, Catherine; Noeel, Catherine; Guyot, Alain; Claverie, Jerome
Year: 1998
Title: Nitroxide Mediated Living Radical Polymerization of Styrene in Emulsion
Journal: Macromolecules
Volume: 31
Issue: 12
Pages: 4041-4044
Abstract: Living radical polymn. in emulsion can be carried out with a nitroxide, a convenient surfactant, potassium persulfate (KPS) for initiator and styrene for monomer. The nature of the surfactant and of the nitroxide strongly dets. the outcome of the reaction. In most cases, low conversion and/or flocculation are obsd., probably because of the extraordinarily harsh conditions necessary to carry out this expt. (135.degree.C for several days). Nevertheless, the combination of amino TEMPO and sodium dodecyl sulfate (SDS) appears to generate satisfying results. Moreover, it seems that the presence of a long alkyl chain alc. is necessary. The stabilization and final conversion are further increased by starting the living polymn. with an hydrosol. monomer such as styrene sulfonate. In this case, each polymer chain carries at least one sulfonate end-group.
Notes: written in English.
15. Reference Type: Journal Article
Author: Guyot, A.; Claverie, J.; Marestin, C.
Year: 1998
Title: Radical capture in emulsion polymerization using particles grafted with nitroxide compounds and further controlled radical polymerization
Journal: Book of Abstracts, 215th ACS National Meeting, Dallas, March 29-April 2
Pages: COLL-032
Abstract: Seeded particles functionalised with surface nitroxide groups have been used to study the entry of oligoradicals of methylmethacrylate and other monomers. The intensity of the ESR signal allows to study the kinetics of this radical entry, as a function of the particle size, the particle surface area and the particle no., allowing to check the various theories of the phenomenon. - At higher temps., it is possible to use such seeded particles carrying the nitroxide groups to analyze the particle growth in the conditions of /"controlled radical polymn./" of styrenic monomers and for their copolymn. with other monomers.
Notes: written in English.
14. Reference Type: Patent
Record Number: 32
Author: Claverie, Jerome P.
Year: 1998
Title: Controlled /"Living/" radical polymerization of styrene with iron complexes
Country: World patent
Pages: P1595-P1604
Number:WO 416036
Keywords: Polymerization catalysts; Polymerization catalysts (living, radical, iron macrocycle complexes; controlled radical polymn. of styrene in presence of)
living radical polymn styrene iron catalyst; polystyrene prepn catalyst iron complex
Abstract: Iron macrocycles were used as additives in the chain growth controlled radical polymn. of styrene, to afford narrowly distributed polymers. This new system can be used in a reversible termination scheme, and also in a double protection scheme which combines the features of atom transfer radical polymn. (ATRP) and reversible termination. The no.-av. mol. wt. of the resulting polymer grows linearly with conversion, and the polydispersity index is below 1.5.
Notes:written in English.
13. Reference Type: Journal Article
Author: Claverie, J.; Marestin, C.
Year: 1997
Title: Living radical polymerization with iron macrocycles
Journal: Book of Abstracts, 214th ACS National Meeting, Las Vegas, NV, September 7-11
Pages: INOR-036
Abstract: Iron macrocycles can act as stabilizers for both iron II and III oxydation degrees. Besides, iron II macrocycles readily trap carbon-centered radicals, and act as persistent radicals (eq. 1). At 80.degree.C, the polymn. of styrene with iron macrocylce exhibits a linear dependence of mol. wt. vs. conversion, but polydispersity indexes (PDI) range from 1.2 to 3, because of a slow irreversible termination step. The kinetic scheme is entirely similar to the living radical polymn. in the presence of nitroxides. Chain transfer to alkyl halides as well as the influence of the ligand on the reaction kinetics are also examd..
Notes:written in English.
12. Reference Type: Journal Article
Author: Elder, Delwin L.; Claverie, Jerome P.; Grubbs, Robert H.
Year: 1996
Title: The alcohol effect in tungsten and molybdenum olefin meta thesis catalysts
Journal: Book of Abstracts, 212th ACS National Meeting, Orlando, FL, August 25-29
Pages: INOR-087
Abstract: Molybdenum and tungsten olefin metathesis catalysts of the type M(=CHR)(=NAr)(OC(CH3)(CF3)2)2 and M(=CHR)(=NAr)(OC(CH3)(CF3)2)2L (M = Mo, W; L = phosphine, phosphite) were studied. Recently, our group has discovered that addn. of one or more equiv. of hexafluoro-tert-butanol (HFB) to a soln. of these catalysts can greatly increase their ring-opening metathesis polymn. (ROMP) activity. Specifically, the rate const. for polymer initiation, ki, increases relative to the rate const. for polymer propagation, kp. Addnl., HFB affects the syn / anti isomerization rates of the carbene fragment and allows for the polymn. of less-strained cyclic olefins. Investigations into the mechanism of this alc. effect have been performed and preliminary results are presented here.
Notes: written in English.
11. Reference Type: Thesis
Record Number: 38
Author: Claverie, Jerome Pierre
Year: 1996
Title: Ring-opening metathesis polymerization with tungsten based catalysts: kinetics, thermodynamics and mechanism
Number of Pages: 200 pp
Notes: California Institute of Technology,Pasadena,CA,USA.
Dissertation
written in English.
10. Reference Type: Journal Article
Author: Claverie, Jerome P.; Elder, Delwin L.; Grubbs, Robert H.
Year: 1995
Title: Ring-opening metathesis polymerization by W and MO catalysts in the presence of tertiary alcohols
Journal: Book of Abstracts, 210th ACS National Meeting, Chicago, IL, August 20-24
Issue: Pt. 1
Pages: INOR-189
Abstract: Metathesis polymn. (ROMP) catalysts M(=X)(=CHR)(OR')2 (M = Mo or W; X = NAr or O; R = alkyl or vinyl, R' = tertiary alkyl) show enhanced activity in the presence of alcs. These catalysts are stable in the presence of large quantities of tertiary alcs., but not with secondary or primary alcs. Extremely fast polymns. can be run in neat tertiary alcs., to give well defined polymers. In rigorously aprotic medium, polymns. can be slower by several orders of magnitude. The consequences of this reactivity enhancement have been explored in terms of mechanistic implications as well as improvement of the polymer synthesis.
Notes: written in English.
9. Reference Type: Journal Article
Author: Chen, Zhong-Ren; Claverie, Jerome P.; Grubbs, Robert H.; Kornfield, Julia A.
Year: 1995
Title: Modeling Ring-Chain Equilibria in Ring-Opening Polymerization of Cycloolefins
Journal: Macromolecules
Volume: 28
Issue: 7
Pages: 2147-54
Abstract: A combined computational and theor. method is developed to predict the equil. ring-chain distribution of the products of ring-opening metathesis polymn. In ring-chain equil., the free energy change of reaction includes an entropic cost assocd. with forming cyclic rather than linear products and an enthalpic cost if ring strain is significant (i.e., for small rings). The entropy change is detd. using statistical mechanics based on the Jacobson-Stockmayer theory. The enthalpy change is computed with a Monte Carlo configurational search using mol. mechanics (MM3). Using the resulting equil. consts., the calcd. distribution of cyclic and linear products is in good agreement with expt.
Notes: written in English.
8. Reference Type: Journal Article
Author: Benedicto, Alto D.; Claverie, Jerome P.; Grubbs, Robert H.
Year: 1995
Title: Molecular Weight Distribution of Living Polymerization Involving Chain-Transfer Agents: Computational Results, Analytical Solutions, and Experimental Investigations Using Ring-Opening Metathesis Polymerization
Journal: Macromolecules
Volume: 28
Issue: 2
Pages: 500-11
Abstract: The no.-av. d.p. and polydispersity index of living polymn. in the presence of chain-transfer agents are calcd. numerically and anal. to det. how the mol. wt. of the polymer can be regulated. The Mayo plot is nearly linear, but (as opposed to a nonliving system) its slope is not equal to ktr/kp in general (where ki, kp, and ktr are the specific rate consts. of initiation, propagation, and chain transfer, resp.), the former differing from the latter by about 0.5-1 order of magnitude when ktr/kp = 0.01-1.0. Plots of the slopes of Mayo plot vs. ktr/kp for different values of kp/ki reveal that only when ktr is equal to or greater than kp by an order of magnitude can the mol. wt. be effectively controlled by addn. of chain-transfer agent. A sufficient amt. of chain-transfer agent is a necessary but not a sufficient condition to ensure monomodal mol. wt. distribution. An exptl. investigation of the kinetics of ring-opening metathesis polymn. (ROMP) of norbornene by Mo(:CHCMe2Ph)(NAr)(OCMe3)2 (Ar = 2,6-diisopropylphenyl) in the presence of neohexene suggests that this ROMP system is adequately described by a relatively simple polymn. scheme.
Notes: written in English.
7. Reference Type: Journal Article
Author: Benedicto, Alto D.; Claverie, Jerome P.; Grubbs, Robert H.
Year: 1995
Title: Molecular weight of chain-transferred polymers in living polymerizations: Comparison between experiment and theory
Journal: Book of Abstracts, 210th ACS National Meeting, Chicago, IL, August 20-24
Issue: Pt. 2
Pages: POLY-072
Abstract: The no.-av. d.p. (Xn) of living systems when chain-transfer agents are added deliberately is derived by expressing the kinetic equations governing the process in terms of moments of distribution. The effect of varying rate of reinitiation is examd. The Mayo equation that is used in detg. Xn for non-living polymn. cannot be used to predict Xn of living systems since it failed to take into account the role of catalyst in controlling mol. wt. of living systems. Although the Mayo slope may be orders of magnitude different from ktr/kp (rate consts. of chain transfer and propagation, resp.), the relationship between them is derived. By using neohexene (a poor chain-transfer agent) and styrene (a good chain-transfer agent) in the living ring-opening metathesis polymn. of norbornene with Mo(=CH-CMe2Ph)(NAr)(OCMe3)2 {Ar = 2,6-diisopropylphenyl} and Mo(=CH-CMe2Ph)(NAr)(OCMe3)2 {Ar = 2,6-diisopropylphenyl}, the generality of the theor. approach is demonstrated by the good agreement between exptl. measured Xn and that calcd. theor.
Notes: written in English.
6. Reference Type: Journal Article
Author: Benedicto, Alto D.; Claverie, Jerome P.; Grubbs, Robert H.
Year: 1995
Title: Molecular weight of chain-transferred polymers in living polymerizations: comparison between experiment and theory
Journal: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry)
Volume: 36
Issue: 2
Pages: 172-3
Accession Number: AN 1996:6596
Abstract: An expression is derived for degree of polymn. for living polymn. when chain-transfer agents are deliberately added and the results are compared with the conventional Mayo equation where there is chain termination. The effect of the catalyst concn. and the chain-transfer agent concn. on the mol. wt. of the polymer was examd., both theor. and exptl.
Notes: written in English.
5. Reference Type: Journal Article
Record Number: 47
Author: Hampton, Philip D.; Wu, Si; Alam, Todd M.; Claverie, Jerome P.
Year: 1994
Title: Synthesis of Allylnickel Aryloxides and Arenethiolates: Study of Their Dynamic Isomerization and 1,3-Diene Polymerization Activity
Journal: Organometallics
Volume: 13
Issue: 5
Pages: 2066-74
Abstract: A new family of allylnickel(II) complexes, [Ni(.eta.3-allyl)(.mu.-X)]2 (X = ArO, ArS), were prepd. by anion metathesis of Na or Li aryloxides or arenethiolates with [Ni(.eta.3-allyl)(.mu.-Br)]2. The complexes are proposed to be dimeric and consist of a mixt. of cis and trans isomers. A dynamic process rapidly equilibrates the cis and trans isomers of the pentafluorophenoxide, 2,6-difluorophenoxide, and 3,5-bis(trifluoromethyl)phenoxide complexes on the 1H-NMR time scale. The 2,6-dimethylphenoxide, 2,6-diisopropylphenoxide, 2,4,6-tris(trifluoromethyl)phenoxide, and pentafluorophenoxide complexes are static at room temp. A variable-temp. NMR study of the 3,5-bis(trifluoromethyl)phenoxide complex provided activation enthalpy and entropy values of 12.9 kcal/mol and -6.6 cal/(K mol), resp. Allyl rotation or cleavage of one of the .mu.-X bridges is proposed as the mechanism for the isomerization. The pentafluorophenoxide, 3,5-bis(trifluoromethyl)phenoxide, and 2,4,6-tris(trifluoromethyl)phenoxide complexes initiate the rapid polymn. of 1,3-cyclohexadiene and 1,3-butadiene to form high-mol. wt. 1,4-linked polymers.
Notes: written in English
4. Reference Type: Journal Article
Record Number: 43
Author: Hamaide, T.; Spitz, R.; Letourneux, J. P.; Claverie, J.; Guyot, A.
Year: 1994
Title: Heterogeneous catalysis for ring opening anionic oligomerization
Journal: Macromolecular Symposia
Volume: 88
Pages: 191-200
Abstract: A review with 21 refs. on new heterogeneous catalysts for ring opening oligomerization obtained by grafting alkyl moieties on silica. Adding alc. in excess causes the formation of aluminum alkoxides and allows the catalytic mode, because of a rapid exchange reaction between the grafted active centers and the free alcs. present in the medium. All the polymer chains are end-capped by these alc. mols., which give functionalized oligomers.
Notes: written in English.
3. Reference Type: Journal Article
Author: Chen, Zhongren; Kornfield, Julia A.; Claverie, Jerome P.; Grubbs, Robert H.
Year: 1994
Title: Ring-chain equilibria in ring-opening metathesis polymerization (ROMP) of cycloolefins
Journal: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry)
Volume: 35
Issue: 1
Pages: 692-3
Abstract: The equil. products of ROMP consist of cyclic and linear chains. To characterize the polymerizability of ROMP monomers, the crit. concn., [Mc], is defined as the total monomer amt. lost to cyclic byproducts. A theor. method was developed to predict the ring-chain distribution, including [Mc]. In ring-chain equil., there is an entropic cost assocd. with forming cyclic rather than linear products, and there may be an enthalpic cost if ring strain is significant (i.e., for small rings.). The entropy change was detd. by using an established statistical method (Monte Carlo/RIS.). The enthalpy change is estd. by a Monte Carlo configuration search using mol. mechanics (MM3.). The calcd. distribution of cyclic and linear products was in good agreement with expt. considering ROMP of cyclooctene.
Notes:written in English.
2. Reference Type: Patent
Author: Spitz, Roger; Claverie, Jerome; Hamaide, Thierry; Forestiere, Alain; Marion, Marie Claire
Year: 1993
Title: Catalytic composition supported on silica and its utilization for the polymerization of heterocyclic compounds
Country: French patent FR 92 6464
Assignee: (Institut Francais du Petrole, Fr.).
Pages: 22 pp
Date: 19920525.
Number: 92-6464
Abstract: The title catalysts, for polymn. of, e.g. epoxides or lactones, are prepd. by forming a suspension of dehydrated silica in aprotic anhyd. liqs., adding aluminoxanes or siloxanes terminated with hydrocarbylaluminum groups and removal of excess, and adding active hydrogen compds. which act as initiating compds. for the polymn. Ethylene oxide was polymd. using a catalyst prepd. by treating silica with triisobutylaluminum and then with dodecanol to give a dodecyl-terminated polyoxyethylene.
Notes: written in French.
1. Reference Type: Journal Article
Author: Claverie, Jerome P.; Gin, Douglas L.; Conticello, Vincent P.; Hampton, Philip D.; Grubbs, Robert H.
Year: 1992
Title: Transition-metal-catalyzed polymerization of cyclohexadiene and substituted cyclohexadienes
Journal: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry)
Volume: 33
Issue: 1
Pages: 1020-1
Abstract: 1,3-Cyclohexadiene (I) and 5-methyl-1,3-cyclohexadiene (II) were homopolymd. in the presence of .pi.-allyl Ni complexes. Copolymers of I with II or 5-butyl-1,3-cyclohexadiene were prepd. using the same catalysts.
Notes: written in English.