Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/0091—Complexes with metal-heteroatom-bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L83/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
  • C08L83/04—Polysiloxanes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/06—Preparatory processes
  • C08G77/08—Preparatory processes characterised by the catalysts used
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/12—Polysiloxanes containing silicon bound to hydrogen
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/20—Polysiloxanes containing silicon bound to unsaturated aliphatic groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/22—Polysiloxanes containing silicon bound to organic groups containing atoms other than carbon, hydrogen and oxygen
  • C08G77/24—Polysiloxanes containing silicon bound to organic groups containing atoms other than carbon, hydrogen and oxygen halogen-containing groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/70—Siloxanes defined by use of the MDTQ nomenclature
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/16—Nitrogen-containing compounds
  • C08K5/34—Heterocyclic compounds having nitrogen in the ring
  • C08K5/3442—Heterocyclic compounds having nitrogen in the ring having two nitrogen atoms in the ring

Definitions

• the present invention relates to a catalytic composition based on a palladium catalyst.
• the Catalyst may optionally be modified by additives such as a nitrogen heterocycle derivative convenient for the preparation of polyaddition- curable polyorganosiloxane compositions.
• the present invention is directed to the employment of a new catalytic composition in a polyaddition heat type curable polyorganosiloxane elastomer.
• a typical addition curable polyorganosiloxane composition involves an addition reaction in the presence of an effective amount of a PGM catalyst, such as platinum or rhodium catalyst, between a "vinylpolysiloxane" and a multi- hydrogen functional silicon-hydride material, such as a "silicon hydride siloxane".
• a PGM catalyst such as platinum or rhodium catalyst
• the "vinylpolysiloxane” can be an polyorganosiloxane having alkenyl radicals, for example vinyl radicals attached to silicon by carbon-silicon bonds.
• the PGM catalyst is employed as a mixture with the vinyl polysiloxane prior to contact with the multi-hydrogen functional silicon-hydride material. Upon mixing the various ingredients, crosslinking or cure, often occurs within seconds at ambient temperatures.
• This invention solves the problem by applying a new catalyst to the system.
• catalysts based on palladium could be efficiently used with polyorganosiloxane having at least one unsaturated group and multi-hydrogen functional silicon-hydride material for obtaining elastomer silicone composition.
• crosslinking or cure does not occur at ambient temperatures.
• the present invention relates mainly to the use of an effective amount of a composition based on a combination of an effective amount of a palladium catalyst to yield a polyaddition heat type curable polyorganosiloxane elastomer.
• the catalyst may be modified by addition of an optional nitrogen heterocycle derivative for preparing a polyaddition type heat curable polyorganosiloxane elastomer.
• polyaddition heat type curable polyorganosiloxane compositions are well known in the art.
• a typical addition curable polyorganosiloxane composition involves an addition reaction in the presence of an effective amount of a PGM catalyst, such as platinum or rhodium catalyst, between a polyorganosiloxane (A) containing at least one unsaturated group and a polyorganohydrogenosiloxane (B).
• the polyorganosiloxane (A) can be an polyorganosiloxane having alkenyl radicals, for example vinyl radicals attached to silicon by carbon-silicon bonds.
• the hydrosilylation reactions concerned by the present invention can be represented as follows :
• the claimed composition is particularly advantageous in regard to the usual catalytic compositions based on platinum because the presence of a catalyst inhibitor is optional.
• Various palladium catalysts can be used in accordance with the present invention and include preferably complexes of Pd° and Pd" .
• the following complexes can be used : Pd(OAc) 2 , Pd 2 (di - benzylidene- acetone) 3 , bis (tri-tert-butylphosphine) palladium(O), palladium (II) acetylacetonate, bis (tricyclohexylphosphine) palladium(O), transdichlorobis (tricyclohexylphosphine) palladium(ll), dichloro (1 ,5- cyclooctadiene) palladium (II), trans- dichlorobis (triphenylphosphine) palladium(ll),.
• the optional additive compounds for the present invention are heterocycle derivatives with a ring size of 5-10 atoms and at least 2 nitrogen atoms. They are particularly useful as ligands for the palladium catalyst.
• the molar ratio of the optional nitrogen derivative to the paladium catalyst ranges from 1 to 10, preferably 2 to 5.
• Yet another object of the invention is to provide a polyaddition heat type curable polyorganosiloxane elastomer, comprising :
• the unsaturated groups of the polyorganosiloxane A are for example C 2 -C 8 alkenyl groups, e.g.: vinyl, allyl, 1-butenyl, 1-hexenyl, etc.
• the unsaturated groups may be bonded to the silicon atoms within the chain and/or right at the end.
• the organic substituents, different from unsaturated groups and hydrogen atom, are for example alkyl, cycloalkyl, aryl, aryalkyl and/or alkylaryl radicals and can be substituted.
• the polyorganosiloxanes (A) and (B) used in the reaction have a molecular mass weight comprised between 10 2 and 10 10 (g/mol).
• the polyorganosiloxanes may comprise from 0.01% to 10% (preferably 0,.1 % to 2%) of unsaturated radicals by weight for the polyorganosiloxane (A) and from 0.001% to 5% (more preferably from 0.005% to 2%) of hydrogen by weight for the polyorganosiloxane (B).
• the vinyl groups in (A) and the hydrogen atoms in (B) are typically bonded to different silicon atoms.
• the weight of the palladium catalytic system (C) calculated as the weight of palladium metal typically ranges from 1 to 10 000 ppm, and preferably from 10 to 1000 ppm, based on the total weight of the polyorganosiloxanes (A) and (B).
• the various bases i. e. : the mixture based on (A), (B), (C) and optionally filler(s) and processing aids, for the subject polyaddition silicone compositions, are well known to those of skill in the art. Most of them are available commercially.
• the polyorganosiloxane (A) is an polyorganosiloxane comprising : • siloxy units of the formula (1) :
• the radicals Z are monovalent hydrocarbon groups which do not adversely affect the activity of the catalyst;
• Z being preferably selected from (i) alkyl groups containing from 1 to 8 carbon atoms, optionally substituted by at least an atom of halogen, (ii) cycloalkyl groups containing from 3 to 8 carbon atoms, optionally substituted by at least an atom of halogen, (ii) aryl groups from 6 to 32 carbon atoms such as xylyl and tolyl and phenyl, optionally substituted by at least an atom of halogen, (iv) alkylaryl groups with alkyl group(s) from 1 to 8 carbon atoms and aryl groups from 6 to 30 carbon atoms, optionally substituted by at least an atom of halogen,
• - and a is 1 or 2
• b is 0, 1 or 2
• with a + b ranges from 1 to 3.
• the polyorganosiloxane (A) comprises at least two radicals T.
• the polyorganosiloxane (A) may have a linear, branched, ring or lattice structure.
• siloxy units of formula (1) are the vinyldimethylsiloxy unit, the vinylphenylmethylsiloxy unit, the vinylsiloxy unit and the vinylmethylsiloxy unit.
• siloxy units of formula (2) are the SiO /2 , dimethylsiloxy, methylphenylsiloxy, diphenylsiloxy, methylsiloxy and phenylsiloxy units.
• the polyorganosiloxane (A) may be constituted solely by units of formula (1) or may additionally contain units of formula (2).
• this latter is preferably an polyorganohydrogenosiloxane comprising : • siloxy units of the formula (3):
• - W are monovalent hydrocarbon groups which do not adversely affect the activity of the catalyst and which has the same definition as Z,
• - and d is 1 or 2
• e is 0, 1 or 2
• d+e having a value from 1 to 3
• the polyorganohydrogenosiloxane (B) comprises at least two hydrogen atoms. • and, if desired, all the other units are units of the average formula (4):
• W is as defined above, and g has a value from 0 to 3. All of the limiting values of a, b, c, d, e and g are included.
• the polyorganosiloxane (B) may be constituted solely by units of formula (3) or may additionally contain units of formula (4).
• the polyorganosiloxane (B) may have a linear, branched, ring or lattice structure.
• the degree of polymerization is 2 or more and is generally less than 5,000.
• units of formula (3) are: H(CH 3 ) 2 Si0 1/2 , HCH 3 SiO 2/2 , H(C 6 H 5 )SiO 2/2 .
• polyorganosiloxane (A) for the polyaddition heat curable polyorganosiloxane elastomer according to the present invention are those comprising : • siloxyl moieties having the general formula (5) :
• radicals Z' represent hydrocarbonated preferably selected in the group consisting of : * alkyl radical, halogenoalkyl having from 1 to 5 carbon atoms and having from 1 to 6 chloride and/or fluorine atoms, * cycloalkyl and halogenocycloalkyl radicals having from 3 to 8 carbon atoms and containing from 1 to 4 chloride and/or fluorine atoms, * aryl, alkylaryl and halogenoaryl radicals having from 6 to 8 carbon atoms and containing from 1 to 4 chloride and/or fluorine atoms,
• radicals T' are unsaturated radicals C 2 -C 6 .
• - x is 0,1 , 2 or 3 ;
• - y is 1 , 2 or 3 ;
• - z is 0,1 , 2 or 3 ;
• the polyorganosiloxane (A) comprises at least two radicals T.
• polyorganohydrogenosiloxane (B) for the polyaddition heat curable organopolysiloxane elastomer according to the present invention are those comprising :
• - x is 0,1 , 2 or 3 ;
• - y is 1 , 2 or 3 ;
• - z is 0,1 , 2 or 3 ;
• polyorganohydrogenosiloxane (B) comprises at least two hydrogen atoms.
• Z' is selected in the group consisting of methyl ; ethyl propyl ; isopropyl ; butyl ; isobutyl ; n-pentyl ; t-butyl ; chloromethyl dichloromethyl ; ⁇ -chloroethyl ; fluoromethyl ; trifluoro cyclopropyl ; phenyl (mono)(di)(tri)(tetra)chlorophenyl ; tolyl ; ⁇ , ⁇ , -trifluorotolyl; xylyl and more preferably is methyl or phenyl, these radicals being optionally halogenated.
• polyorganosiloxanes (A) are dimethylpolysiloxanes with dimethylvinylsiloxy end groups, the methylvinyldimethylpolysiloxane copolymers with trimethylsiloxy end groups, methylvinyldimethylpolysiloxane copolymers with dimethylvinylsiloxy end groups and cyclic methylvinylpolysiloxanes.
• polyorganohydrogenosiloxanes (B) are dimethylpolysiloxanes with hydrodimethylsilyl end groups, dimethylhydromethylpolysiloxane copolymers with trimethylsiloxy end groups, dimethylhydromethylpolysiloxane copolymers with hydrodimethylsiloxy end groups, hydromethylpolysiloxanes with trimethylsiloxy end groups, cyclic hydromethylpolysiloxanes and copolymers methylhydrogenomethyloctylsiloxane copolymers.
• the polyorganosiloxane (A) includes in particular with regard to dynamical viscosity at 25°C the following polyorganosiloxanes :
• LSR liquid elastomer silicones
• the claimed polyorganosiloxane compositions are vulcanisable by heating (EVC) by polyaddition and include polyorganosiloxane A1 and a polyorganohydrogenosiloxane B having a viscosity of 10 2 to 10 7 mPa.s at 25°C.
• the polyaddition silicone compositions according to the invention may additionally comprise reinforcing or semireinforcing or extending fillers (E), which are preferably siliceous fillers.
• the reinforcing fillers are selected from the pyrogenic silicas and precipitated silicas. They have a specific surface area, measured according to the BET method, of at least 50 m 2 /g, preferably greater than 70 m2 /g, a mean primary particle size of less than 0.1 micrometer and an apparent density of less than 200 g/liter.
• silicas may be incorporated as such or preferably after they have been treated with organosilicon compounds usually employed for this purpose.
• These compounds include methylpolysiloxanes such as hexamethyldisiloxane and octamethylcyclotetrasiloxane, methylpolysilazanes such as hexamethyl- disilazane and hexamethylcyclotrisilazane, chlorosilanes such as dimethylchlorosilane, trimethylchlorosilane, methylvinyldichlorosilane and dimethylvinylchlorosilane, and alkoxysilanes such as dimethyldimethoxysilane, dimethylvinylethoxysilane and trimethylmethoxysilane.
• the silicas may increase in their initial weight up to a proportion of 20%, preferably approximately 18%.
• the semireinforcing or extending fillers have a particle diameter greater than 0.1 micrometer and are preferably selected from among ground quartz, calcined clays and diatomaceous earths.
• filler (E) may generally be employed per 100 parts of the total amount of the polyorganosiloxanes (A)+(B).
• compositions according to the invention may be kneaded could as such and may be extruded or molded in the form of unit modules (elements); the composition may, for example, be molded into the shape of a cylinder with a diameter of from 0.5 to 9 cm.
• the silicone composition cylinders which are obtained may be cut to the desired length, in the case of their being employed in boreholes, such that the cylinder contains a sufficient quantity of iodine equivalent for a release over preferably at least one year. At the end of this period, the cylinders are replaced.
• the present invention concerns also said silicone composition in crosslinked elastomeric state.
• the present invention is also directed to shaped article comprising the claimed silicone composition curable, or cured by hydrosilylation in crosslinked elastomeric state or not.
• shaped article comprising the claimed silicone composition curable, or cured by hydrosilylation in crosslinked elastomeric state or not.
• Said reaction mixture is a low viscosity oil. Said reaction mixture is covered and stored at room temperature. Said reaction mixture remains a low viscosity oil when stored at room temperature for 8 weeks.
• reaction mixture 10 ⁇ L of said reaction mixture is placed in a DSC pan. DSC is run at 5°C/min from 25°C to 200°C. Said reaction mixture shows an exotherm onset at 175°C and an exothem peak at 180°C.
• Said reaction mixture and said reference vessel are place in an insulated block and the samples and block are placed in a convection oven.
• the oven is heated at 0.5°C/min.
• An infrared camera is used to monitor the samples through a port in the top of the oven (see WO 98/15813).
• Samples are allowed to cool to room temperature and are removed from the oven. Said reference vessel remains a low viscosity oil while said reaction mixture is a cured sample that will not flow.
• Silicon hydride oil, silicon vinyl oil, and a solution of palladium acetate in toluene (10mg/mL) are purged with argon and are introduced into a dry box that excludes water and oxygen. Components are added to form a reaction mixture as described above. Said reaction remains an uncured, low viscosity oil at room temperature. Said reaction mixture is placed on a heating block and is heated to 180°C. When held at high temperature in said dry box for 1 hour, said reaction remains an uncured, low viscosity oil.
• Silicon hydride oil, silicon vinyl oil, water, and a solution of palladium acetate in toluene (10mg/mL) are purged with argon and are introduced into a glove box that excludes oxygen.
• Water is added to the palladium toluene solution to make give 5 molar equivalents of water to palladium.
• Components are added to form a reaction mixture as described above. Said reaction remains an uncured, low viscosity oil at room temperature.
• Said reaction mixture is placed on a heating block and is heated to 180°C.
• Said reaction mixture changes from a low viscosity oil to a non-flowable, cured system within 5 minutes at elevated temperature.

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• 2001
  • 2001-12-19 EP EP01995727A patent/EP1456301A1/de not_active Withdrawn
  • 2001-12-19 AU AU2002226403A patent/AU2002226403A1/en not_active Abandoned
  • 2001-12-19 JP JP2003552867A patent/JP2005513185A/ja active Pending
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