Showing papers on "Ring-opening metathesis polymerisation published in 1991"
257 citations
154 citations
TL;DR: In this paper, the authors add the addition du dimere du norbornadiene ou polynorbornene obtenu par polymerisation par metathese amorcee par (CHR) (NR) (O-t-Bu) 2 (M=Mo, W) donne des polymeres en etoile.
Abstract: L'addition du dimere du norbornadiene ou polynorbornene obtenu par polymerisation par metathese amorcee par (CHR) (NR) (O-t-Bu) 2 (M=Mo, W) donne des polymeres en etoile. Des copolymeres en etoile sont prepares par reaction du 2,3-bis (trifluoromethyl)- ou du 2,3-bis(methoxycarbonyl)-norbornadiene avec le poly(5-cyanonorbornene) vivant en etoile obtenu par cette methode
82 citations
TL;DR: In this paper, a ring-opening polymers of norbornenes with SiMe3 and Si(Me2)CH2SiMe3 groups were synthesized and mass transfer properties of the polymers were studied.
Abstract: Polymers of norbornenes with SiMe3 and Si(Me2)CH2SiMe3 groups were synthesized and mass transfer properties of the polymers were studied. Ring-opening polymerizations of these monomers were realized in the presence of homogeneous WCl6-based and heterogeneous Re2O7-based metathesis catalysts. Introduction of silicon-containing groups in the polynorbornene main chain results in a drastic increase of the permeability (P) and diffusion (D) coefficients for different biatomic and multiatomic gases. Comparison of polymers having SiMe3 and Si(Me2)CH2SiMe3 substituents shows lower permeability and diffusion coefficients in the latter case. The combination of transport properties (Pi values) and separation factors aij = Pi/Pj of the two new silicon-containing polynorbornenes permits one to consider them as representatives of the most permeable and sufficiently permselective group of polymers. Transport properties of the polymers studied were analysed on the basis of the free volume approach.
65 citations
TL;DR: A review of titanacyclobutane-initiated "living" olefin metathesis polymerization for the preparation of new polymer structures is given in this paper, where the same type of reaction was used to link preformed polymer blocks to give ABA-type triblock copolymers and graft Copolymers.
38 citations
TL;DR: In this paper, the trichlorides of ruthenium and osmium were used as precursors to the initiating and chain propagating species to yield poly(2,5]-3,4-bis(carboxylic acid)furanylene]vinylene)s.
37 citations
TL;DR: Diblock copolymers of norbornene and Sn[2,3-transbis-([tert-butylamido]methyl)norborn-5-ene]Cl 2 were prepared by ring opening metathesis polymerization using a tungstene alkylidene catalyst as discussed by the authors.
Abstract: Diblock copolymers of norbornene and Sn[2,3-trans-bis-([tert-butylamido]methyl)norborn-5-ene]Cl 2 were prepared by ring opening metathesis polymerization using a tungstene alkylidene catalyst. TEM and SAXS data showed that these copolymers exhibited spherical, cylindrical or lamellar morphology depending on their composition and molecular weight. The phase diagram compared well with the predictions of the Helfand and Wasserman theory.
35 citations
TL;DR: The mechanism for the initiation of olefin metathesis over the heterogeneous catalyst rhenium heptoxide on γ-alumina was studied in this paper, using a pulse catalytic microreactor.
33 citations
Patent•
24 Sep 1991TL;DR: In this article, a two component catalyst system for the polymerization of metathesis polymerizable cycloolefins was proposed, consisting of a pure tungsten-imido compound (procatalyst) of the formula W(NR.sup.sub.x.1)X.L.
Abstract: This invention relates to a two component catalyst system for the polymerization of metathesis polymerizable cycloolefins, comprising (a) a pure tungsten-imido compound (procatalyst) of the formula W(NR.sup.1)X.sub.4-x (OR.sup.2).sub.x.L.sub.y wherein x=0, 1, 2, 3 or 4; y=0 or 1; R 1 and R 2 are alkyl, phenyl, phenyl-substituted phenyl, phenylalkyl or halogen substituted derivatives of alkyl, phenyl, phenyl-substituted phenyl or phenylalkyl; X=Br or Cl; where alkyl has 1 to 8 carbon atoms, phenyl-substituted phenyl has 12-18 carbon atoms and phenylalkyl has 7 to 20 carbon atoms; L is a donor ligand; and (b) an activator compound selected from organometals and organometal hydrides with tri-n-butyltin hydride and tri-octyltin hydride the most preferred. This invention also relates to a process for preparing thermoset molded articles possessing low levels of residual monomer using a ring-opening metathesis polymerization by reaction injection molding using the two component catalyst system of this invention and the polymer prepared by this process.
28 citations
TL;DR: In this article, the influence of the diester structure on the molecular weight values was also studied in detail, and a possible reaction mechanism was proposed. But none of the results were considered in this paper.
23 citations
Patent•
04 Jan 1991TL;DR: The rhenium (VII) compounds as discussed by the authors are catalysts for metathesis of ordinary olefins (hydrocarbons) and functionalized olefs in a homogeneous phase and methods of synthesizing these compounds.
Abstract: The invention pertains to rhenium (VII) compounds which are catalysts for metathesis of ordinary olefins (hydrocarbons) and functionalized olefins in a homogeneous phase and to methods of synthesizing these compounds. The rhenium compounds comprise a rhenium (VII) atom centrally linked to an alkylidene ligand, an alkylidyne ligand, and two other ligands of which at least one ligand is sufficiently electron withdrawing to render the rhenium atom significantly active for metathesis.
TL;DR: Preparation des polymeres tBu-CH(=CH-(C 5 H 8 )-CH) n =CH-PhX (X=OMe, NMe 2, CN, NO 2, CHO, CO 2 MC, NH 2, CF 3 -Cl) par reaction du polymere vivant avec le benzaldehyde substitue correspondant
Abstract: Preparation des polymeres tBu-CH(=CH-(C 5 H 8 )-CH) n =CH-PhX (X=OMe, NMe 2 , CN, NO 2 , CHO, CO 2 MC, NH 2 , CF 3 -Cl) par reaction du polymere vivant avec le benzaldehyde substitue correspondant
TL;DR: The chloro-aryloxide complexes of tungsten WCl 6-χ (OAr) χ (χ = 2, 3, 4; OAr = substituted phenoxide), when associated with alkyl-aluminium compounds, are effective catalysts in the ring-opening metathesis polymerization of dicyclopentadiene.
TL;DR: In this paper, aqueous ring opening metathesis polymerisation (ROMP) of exo,exo-5,6-bis(methoxymethyl)-7-oxabicylo[2.2.1]hept-2-ene, was characterised by high field NMR.
Abstract: Poly(2,5-(3,4-bis(methoxymethyl)furanylene)vinylene)s of various microstructures, prepared by aqueous Ring Opening Metathesis Polymerisation (ROMP) of exo,exo-5,6-bis(methoxymethyl)-7-oxabicylo[2.2.1]hept-2-ene, were characterised by high field NMR.
TL;DR: In this paper, the effect of the side group on the optical, electrical and materials properties of the polymer is discussed, as well as its properties in terms of conjugation and binding properties.
TL;DR: In this paper, the catalytic activity in olefin metathesis is described for the systems formed in the reactions between WCl6, WOCl4, WBr5 and MoOCl 4 and the hydroxyl groups of the inorganic gels alumina, silica and silica-alumina, and after activation by tetraalkyl tin or lead.
TL;DR: Acyclic diene metathesis (ADMET) polymerization offers a new opportunity to generate a wide variety of elastic structures using room temperature reaction conditions as discussed by the authors, and it also offers the opportunity to modify existing elastomer structures through trans-metathesis copolymerization reactions.
Abstract: Acyclic diene metathesis (ADMET) polymerization offers a new opportunity to generate a wide variety of elastic structures using room temperature reaction conditions. It also offers the opportunity to modify existing elastomer structures through trans-metathesis copolymerization reactions. ADMET depolymerization could have tremendous significance if, in fact, the reaction can be applied to the recovery of commercial vulcanized elastomers. All of these opportunities are presently being investigated in our laboratory.
TL;DR: In this paper, the interaction between catalyst precursors, Lewis acid (AlCl3) and alkylating agent (Et4Sn) allowed the determination and characterization of the subsequent stages of formation of the catalytically essential carbene dmitrosylmolybdenum complexes.
Journal Article•
TL;DR: The cyclic olefins cyclopentene, norbornene, exo-and endodicyclopentadiene were homopolymerized by Mo (CO)5py/C2H5AlCl2/(C4H9)4NCl as mentioned in this paper.
Abstract: The cyclic olefins cyclopentene, norbornene, exo- and endodicyclopentadiene, exo, exo-norbornadiene dimer, and indene were homopolymerized by Mo (CO)5py/C2H5AlCl2/(C4H9)4NCl. In most cases, the polymers obtained were of the ring-opened type, but also showed ringretention to varying degrees, depending on the temperature of polymerization. Generally, ring-opening polymerization was favored at lower temperatures. The dicyclopentadiene monomers gave crosslinked materials, showing reaction through both double bonds.
TL;DR: In this article, a ring opening metathesis polymerization (ROMP) of 2-trimethylsilylbicyclo [221]-hept-2,5-diene (I) with a tungsten hexachloride/tetramethyltin co-catalyst system yields poly[(2-trimateylsilyl-2-cyclopentene-1,4-diyl) vinylene] (II) has been characterized by1H,13C,29Si, IR and UV-VIS spectroscopy
Abstract: Ring opening metathesis polymerization (ROMP) of 2-trimethylsilylbicyclo [221]-hept-2,5-diene (I) with a tungsten hexachloride/tetramethyltin co-catalyst system yields poly[(2-trimethylsilyl-2-cyclopentene-1,4-diyl) vinylene] (II) The product polymer (II) has been characterized by1H,13C,29Si, IR and UV-VIS spectroscopy Its molecular weight distribution has been determined by gel permeation chromatography (GPC), its thermal stability by thermogravimetric analysis (TGA) and its glass transition temperature (Tg) by differential scanning calorimetry (DSC)
TL;DR: In this paper, a new highly active catalysts for metathesis of olefins were obtained through the interaction of bis(acetylacetonato)dioxymolybdenum(VI) with surface OH groups of γ-Al2O3 and subsequent reduction in H2 or CO.
Abstract: New highly active catalysts for metathesis of olefins were obtained through the interaction of bis(acetylacetonato)dioxymolybdenum(VI) with surface OH groups of γ-Al2O3 and subsequent reduction in H2 or CO.
TL;DR: In this paper, a ring opening metathesis using tungsten hexachloride and either cyclopentene or cyclohexene as an initiator, with or without tetraphenyltin as a cocatalyst, was used to polymerize 1,1-diphenyl-1-sila-cis-pent-3-ene.
Abstract: 1,1-Diphenyl-1-silacyclopent-3-ene (I) has been polymerized by ring opening metathesis using tungsten hexachloride and either cyclopentene or cyclohexene as an initiator, with or without tetraphenyltin as a cocatalyst. The product polymer poly(1,1-diphenyl-1-sila-cis-pent-3-ene) (II) has been characterized by1H,13C, and29Si NMR and IR spectroscopy.
TL;DR: In this paper, the metathesis of 2-octene using the W(CO)6/hv/CCl4 catalyst system was studied in photo-induced and photoactive reaction conditions.
TL;DR: In this article, a ring opening metathesis polymerization (ROMP) of 2-dimethylsilylbicyclo[2.2.1]hept-2,5-diene (I) cocatalyzed by tungsten hexachloride/terramethyltin yields poly[(2dimethyl-silyl-2-cyclopentene-1,4-diyl) vinylene] (II).
Abstract: Ring opening metathesis polymerization (ROMP) of 2-dimethylsilylbicyclo[2.2.1]hept-2,5-diene (I) cocatalyzed by tungsten hexachloride/terramethyltin yields poly[(2-dimethyl-silyl-2-cyclopentene-1,4-diyl) vinylene] (II). This is the first example of ROMP of a monomer which contains a reactive Si-H bond. 1H, 13C, 29Si and IR spectroscopy were utilized to characterize II. The molecular weight distribution of II has been determined by gel permeation chromatography (GPC), its thermal stability by thermogravimetric analysis (TGA) and its glass transition temperature (Tg) by differential scanning calorimetry (DSC).
TL;DR: In this paper, it was found that methyl (Z,E or E,Z)-3,7-cyclodecadienecarboxylate undergoes ring opening metathesis polymerization by the catalyst system WCl 4 (OAr) 2 /PbEt 4 to afford a 1:2 copolymer of methyl acrylate and butadiene.
Abstract: It was found that methyl (Z,E or E,Z)-3,7-cyclodecadienecarboxylate undergoes ring opening metathesis polymerization by the catalyst system WCl 4 (OAr) 2 /PbEt 4 to afford a 1:2 copolymer of methyl acrylate and butadiene.
TL;DR: The ring opening metathesis polymerisation (ROMP) of 5-cyano-2-norbornene with tungsten hexachloride, tungesten oxytetrachlorides, bis(dichloralkoxo)tungsten tetrachoride and bis(Dichloroxo)-tungstens oxydichloride as transition metal component was studied.
Abstract: Die ringoffnende metathetische Polymerisation (ROMP) von 5-Cyano-2-norbornen wurde unter Einsatz von Wolframhexachlorid, Wolframoxidterachlorid, Bis(dichloralkoxo)wolframtetrachlorid und Bis(dichloralkoxo)wolframoxiddichlorid als Ubergangsmetallkomponente untersucht. Als Cokatalysatoren dienten Methylaluminoxan, Diethylaluminiumethoxid, Tetraisobutyldialuminoxan und Tetrabutylzinn. Als Losungsmittel wurden Toluol, Chlorbenzol und Dichlormethan verwendet. Die Konzentration der Wolframkomponente lag im Bereich 5 × 10−4 − 5 × 10−3 mol/l. Unter den gepruften Katalysatoren erwies sich Wolframhexachlorid in Verbindung mit Diethylalumiumethoxid als der geeignetste. Mit diesem System verlief die Polymerisation auch bei grosen Monomer/Wolfram-Verhaltnissen (10200 :1) hochselektiv und fuhrte zu grosen Umsatzen (≥82%).
The ring opening metathesis polymerisation (ROMP) of 5-cyano-2-norbornene with tungsten hexachloride, tungesten oxytetrachloride, bis(dichloralkoxo)tungsten tetrachloride and bis(dichloralkoxo)tungsten oxydichloride as transition metal component was studied. Methylaluminoxan, diethylaluminium ethoxide, tetraisobutyldialuminoxan and tetrabutyltin served as cocatalyst. Toluene, Chlorobenzene and dichloromethane were used as solvents. The concentration of the tungsten components was in the range from 5 × 10−4 to 5 × 10−3 mol/l. Among the catalyst studied, tungsten hexachloride with diethylaluminium ethoxide proved to be the best. The polymerisation was highly selective with this system even at high monomer/tungsten ratios (e.q. 10200:1) and let to high conversions (≥82%).