2217 results about "Platinum catalyst" patented technology

A silicone rubber composition comprising (A) an organopolysiloxane containing at least two aliphatic unsaturated bonds, (B) an organopolysiloxane of resin structure comprising SiO₂ units, R³_nR⁴_pSiO_0.5 units and R³_qR⁴_rSiO_0.5 units wherein R³ is vinyl or allyl, R⁴ is a monovalent hydrocarbon group free of aliphatic unsaturation, n is 2 or 3, p is 0 or 1, n+p=3, q is 0 or 1, r is 2 or 3, q+r=3, (C) an organohydrogenpolysiloxane having at least two SiH groups, and (D) a platinum catalyst cures into a silicone rubber having excellent rubbery and strength properties and little surface tack.

The invention discloses a halogen-free flame-retarded heat-conducting organic silicon electronic potting adhesive and a preparation method thereof. The preparation method comprises: adding vinyl dimethicone, a reinforcing material, a heat-conducting filling material and a halogen-free flame retardant in a vacuum kneader, dehydrating and blending for 30-120 minutes at 100-150 DEG C and vacuum degree of 0.06-0.1MPa to obtain a base material, adding a cross-linking agent containing hydrogen silicone oil and a cross-linking inhibitor to the base material at the normal temperature, adequately agitating for 10-30 minutes to prepare a component A; adding a platinum catalyst to the base material, adequately agitating for 10-30 minutes to prepare a component B; taking the component A and the component B of the same parts by weight, blending uniformly, and deaerating for 5-10 minutes at the vacuum degree of 0.06-0.1MPa to obtain the halogen-free flame-retarded heat-conducting organic silicon electronic potting adhesive. The potting adhesive has good flow properties and convenient use and can be cured at the normal temperature or a high temperature, condensate has excellent flame retardant property and heat-conducting property, and the potting adhesive can be widely applied to the fields of electronic electric appliance, chip encapsulation and LED encapsulation, and the like.

A carbonylation catalyst useful for producing esters and carboxylic acids in a vapor phase carbonylation process, wherein the catalyst includes a solid component having a catalytically effective amount of platinum and tin associated with a solid catalyst support material and a vaporous halide promoter component.

An engine exhaust catalyst exhibits improved CO oxidation performance relative to conventional engine exhaust catalysts and includes a first supported catalyst comprising platinum and a second supported catalyst comprising palladium and gold species in close contact. The first supported catalyst may be a platinum catalyst, a platinum-palladium catalyst, or a platinum catalyst promoted with bismuth, and the second supported catalyst preferably has a palladium to gold weight ratio of about 0.85:1.0. To improve aged catalyst performance, the first and second supported catalysts are coated onto different layers, zones, or monoliths of the substrate for the engine exhaust catalyst.

Fatty alcohol or aliphatic glycol-grafted rubber-like silicone gels with enhanced oil compatibility are synthesized by 1) reacting a fatty alcohol or a aliphatic glycol with methylhydrodimethylsiloxane copolymer in the presence of a platinum catalyst in a reaction medium of a silicone fluid or a cosmetic oil or a mixture thereof, and 2) further reacting the mixture with a vinyl-functional siloxane polymer. The resulting compounds may be used as gelling agents for hydrocarbon oils, vegetable oils and silicone oils. The efficient synthetic process approaches a 100% yield.

A hydrosilation processing a silicon hydride with an unsaturated reactant in the presence of a supported bimetallic catalyst comprising an active hydrosilating metal such as platinum in elemental or compound form, and a surface segregating metal such as copper in elemental or compound form on a support.

The invention discloses a high temperature resistant heat-conducting silica gel sheet and a preparation method thereof. The high temperature resistant heat-conducting silica gel sheet is characterized by comprising the following components in parts by weight: 50-80 parts of vinyl end capped polydimethylsiloxane (PDMS), 20-50 parts of vinyl end capped methyl phenyl silicone oil, 0.3-10 parts of containing hydrogen silicone oil, 2-6 parts of platinum catalyst, 0.2-0.6 parts of inhibitor, 5-100 parts of heat resistant additive and 400-1200 parts of heat-conducting powder. The preparation method of the high temperature resistant heat-conducting silica gel sheet comprises the following steps: firstly, uniformly mixing the vinyl end capped polydimethylsiloxane and the vinyl end capped methyl phenyl silicone oil in a kneading machine; adding the treated or untreated heat-conducting powder and the heat resistant additive which are added in batches, after mixing uniformly, adding the containing hydrogen silicone oil, the inhibitor and the catalyst; and mixing uniformly, and heating and solidifying in a forming machine to form a sheet. The heat resistant silica gel sheet provided by the invention is aged at 250 DEG C for 1000 hours, but still has good usability, and the changes of the hardness and the heat conductivity coefficient are within acceptable ranges.

The invention relates to silicon rubber with high refractive index and high transparency for optical encapsulation and a preparation method thereof. The silicon rubber is prepared from a phenyl vinyl polysiloxane component A, a silicon resin component B containing phenyl vinyl, a phenyl component C containing hydrogen polyoxyalkylene, a platinum catalyst component D, a catalytic inhibitor component E, a modified polysiloxane component F, and a water remover component G in a mixing manner. The silicon rubber not only has over 1.50 of refractive index, but also is good in transparency, excellent in adhesion, and stable in performance, can resist heat and ultraviolet radiation for a long period of time, can meet various requirements of LED (light-emitting diode) encapsulation, and is an ideal encapsulation material of the LED. The silicon rubber can be packaged into a bi-component product; the product has good storage stability; and high transparency is still kept after the product is stored for over 6 months.

The invention relates to a preparation method of organic silicon rubber for encapsulating LED being convenient for vacuum defoamation, which aims at solving the technical problems that the surface tension of LED encapsulating silicon rubber is reduced, so the LED encapsulating silicon rubber is convenient for the vacuum defoamation, and the transmittance of the product is improved. The method comprises the following steps that: 1) transparent vinyl silicon oil containing methyl trifluoropropyl silica chain link and methyl-phenyl silica chain link is prepared; 2) transparent vinyl silicon oil is configured with methyl-phenyl hydrogen-containing silicon oil, platinum catalyst and inhibitor to A/B rubber; the mol ratio of Si-H and Si-Vi is 0.8 to 3: 1; the hydrogen content of the methyl-phenyl hydrogen-containing silicon oil is 1.6 to 1.0*10<-6> percent by weight; 3) A/B rubber is uniformly mixed, after being vacuum defoamed at the room temperature, the mixture is vulcanized to a product.

An engine exhaust catalyst exhibits improved CO oxidation performance relative to conventional engine exhaust catalysts and includes a first supported catalyst comprising platinum and a second supported catalyst comprising palladium and gold species in close contact. The first supported catalyst may be a platinum catalyst, a platinum-palladium catalyst, or a platinum catalyst promoted with bismuth, and the second supported catalyst preferably has a palladium to gold weight ratio of about 0.85:1.0. To improve aged catalyst performance, the first and second supported catalysts are coated onto different layers, zones, or monoliths of the substrate for the engine exhaust catalyst.

Curable addition crosslinkable organopolysiloxane materials employing a platinum catalyst selected from the group consisting of compounds of the formulaand/or oligomeric or polymeric compounds which are composed of structural units of the general formulaand optionally structural units of the general formulain whichR2, R3, R4, R6, R7, R8, R9, r, s and t have the meanings stated in claim 1, may be prepared as one-component formulations having prolonged shelf life, or as two-component formulations having prolonged pot life, while maintaining desirable chemical and physical properties.

The present invention relates to a method for deuteration of a compound having an aromatic ring, using an activated catalyst, and the method comprises reacting a compound having an aromatic ring with heavy hydrogen source in the presence of an activated catalyst selected from a platinum catalyst, a rhodium catalyst, a ruthenium catalyst, a nickel catalyst and a cobalt catalyst.

A diesel exhaust treatment system and method of oxidizing NO to NO2 at low temperatures are provided. The system utilizes a platinum catalyst on a zirconia-stabilized silica support which oxidizes NO in the exhaust gas to NO2 and uses the NO2 in an amount sufficient to oxidize particulate trapped on a particulate filter. The catalyst is preferably pre-treated at a temperature of between about 500 to 650° C. in a NO-oxygen-nitrogen mixture to increase conversion at low temperatures. The catalyst preferably includes an additional oxide component selected from the group consisting of TiO2, P2O5, WO3, B2O3, and Al2O3. or a heteropolyacid component to further increase activity at low temperatures or to decrease platinum loading at the same level of performance.

The invention relates to environmental-friendly synthetic organosilicon leather and a method for producing the same. The synthetic organosilicon leather comprises vinyl polysiloxane gum, white carbon black, a structured treatment agent, a plastifying agent, an inhibitor, hydrogen containing silicone oil, a platinum catalyst and silicone rubber masterbatch. The method for producing the synthetic organosilicon leather comprises the following steps: mixing the raw materials to obtain solid mixed silicone rubber through vulcanization via addition, rolling the solid mixed silicone rubber by a multi-roll rolling machine to fit textile-based fabric, heating and vulcanizing to form the synthetic organosilicon leather. The environmental-friendly synthetic organosilicon leather is efficiently produced with a simple process and can be produced on a large scale. The produced synthetic organosilicon leather has good mechanical properties and excellent characteristics of being resistant to high andlow temperature, weathering aging and physical inertia, is easy to cut and sew and is waterproof and breathable. The combustion and decomposition product of the synthetic organosilicon leather contains no harmful substance, can be recycled and accords with environmental protection requirements.

The crosslinkable rubber composition is crosslinkable at room temperature, has a gelation time at room temperature of 30 days or less, and can prepare a crosslinked rubber sheet by crosslinking the composition at room temperature, wherein the crosslinked rubber sheet has a tensile elongation of 20% or more, and is free of cracks after treatment at 40° C. in a 50 pphm ozone concentration for 96 hr. Specifically, it comprises an ethylene/alpha-olefin/non-conjugated polyene random copolymer rubber comprising a norbornene compound having a specific vinyl end group, an SiH group-containing compound, which has at least two SiH groups in one molecule, and optionally a platinum catalyst, a reaction inhibitor and/or a silane-coupling agent. The sealing, potting and coating materials and adhesives of the present invention comprise the above rubber composition. The rubber composition has a high crosslinking rate at room temperature and excellent productivity, and can prepare crosslinked rubber molded products (including foamed products) having excellent weathering resistance, ozone resistance, heat aging resistance and compression set at low cost. Further, it is suitable for use of electric and electronic parts, transportation machines, civil engineering and construction materials, medical appliances and goods for leisure activities.

The invention relates to an addition type heat-conducting silicone rubber and a preparation method thereof. The addition type heat-conducting silicone rubber is characterized in that 100 weight portions of vinyl silicone oil and 200 weight portions to 500 weight portions of heat-conducting material are dewatered and mixed in a vacuum kneader for 30 to 200 minutes with the temperature of 100 to 150 DEG C and the vacuum degree of 0.06 to 0.099 MPa so as to obtain base material; under normal temperature, 0.5 weight portion to 1.5 weight portions of hydrogeneous silicone oil, 0.01 weight portion to 0.06 weight portion of inhibitor and 3 weight portions to 10 weight portions of diluent are added and stirred in a stirrer for 15 to 40 minutes so as to obtain A glue; 100 weight portions of base material are taken, 0.25 weight to 0.75 weight portion of platinum catalyst and 3 weight portions to 10 weight portions are added and stirred in the stirrer for 15 to 40 minutes so as to obtain B glue. The A glue and the B glue with the same weight portions are taken, mixed evenly and defoamed for 3 to 10 minutes at the vacuum degree of 0.06 to 0.09 MPa so as to obtain addition type heat-conducting silicone rubber. The heat-conducting silicone rubber is cured at normal temperature or low temperature, has good flow property and convenient use, has higher heat conductivity after fluidization and can be used for the components with the need of heat dissipation and heat transmission in the electronic appliance field.

The invention relates to a liquid silicon rubber composition which comprises the following components in parts by mass: 100 parts of polydimethylsiloxane with vinyl as an end group, 1-400 parts of inorganic reinforcing agent, 1-20 parts of low-viscosity polydimethylsiloxane with a vinyl-containing side group, 0.01-10 parts of cross-linking agent, 1-30 parts of polydimethylsiloxane with hydroxyl as an end group, and a platinum catalyst capable of curing the liquid silicon rubber composition. The invention further relates to a preparation method of the liquid silicon rubber composition. The liquid silicon rubber composition has low viscosity and good fluidity before being cured and is applicable to injection molding; and the composition has excellent resilience and low compression deformation ratio after being cured. The liquid silicon rubber composition can be applied to an elastomer, a pressure roll and an image heating and fixing device in a copier and a laser printer as well as certain silicon rubber products in need of the properties.

The invention relates to a monocomponent addition type silicone rubber packaging glue with strong cohesiveness and a preparation method thereof. The packaging glue comprises, by weight, 80-120 parts of vinyl silicone oil, 5-20 parts of vinyl silicone resin, 10-30 parts of hydrogen-containing silicone oil, 1-3 parts of white carbon black, 1-5 parts of titanium dioxide, 0.1-0.5 part of inhibitor and 0.1-0.5 part of platinum catalyst. The preparation method comprises steps of: first mixing vinyl silicone oil, vinyl silicone resin, hydrogen-containing silicone oil, organic polysiloxane adhesion agent, white carbon black and titanium dioxide by high speed stirring; then adding inhibitor and mixing by high speed stirring; finally adding platinum catalyst and mixing by middle speed stirring; and discharging. After sulfuration, the monocomponent addition type silicone rubber packaging glue prepared by the method of the invention has a bonding strength with a base material (copper) higher than 1.86 MPa.

The present invention relates to a low-oil-permeability super-soft thermally-conductive silica gel composition and a thermally-conductive silica gel gasket, the low-oil-permeability super-soft thermally-conductive silica gel composition comprising a first liquid silica gel, a second liquid silica gel and a thermally-conductive filler, the thermally-conductive silica gel gasket is prepared from the low-oil-permeability super-soft thermally-conductive silica gel composition, the low-oil-permeability super-soft thermally-conductive silica gel composition is prepared from the following components by mass: 7 to 11.9% of a first liquid silica gel and second liquid silica gel mixed liquid, 88 to 92.9% of the thermally-conductive filler, 0.05 to 0.5% of a catalyst and 0.05 to 0.5% of an inhibitor by the preparation method comprising stirring, rolling, vulcanizing and cutting; the low-oil-permeability super-soft thermally-conductive silica gel composition is prepared by mixing the first liquid silica gel, the second liquid silica gel and the thermally-conductive filler, vinyl silicone oil and a platinum catalyst in the first liquid silica gel and vinyl silicone oil and hydrogen-containing silicone oil in the second liquid silica gel can make the prepared plastic material characterized by being low in oil permeability and low in hardness, and the like, the viscosity of the first liquid silica gel and the second liquid silica gel are 3000mPa. s-10000mPa.s, uniform mixing of the material and the thermally-conductive filler during stirring can be guaranteed, and an appropriate crosslinking degree can be achieved during the vulcanizing.