Abstract: A hot melt sealant/adhesive composition is provided which comprises the following components—Component A. a siloxane polymer composition comprising a) An organopolysiloxane which may comprise not less than two groups selected from i) silicon bonded alkenyl groups or ii) silicon-bonded hydroxyl groups and/or silicon bonded hydrolysable groups b) one or more fillers; and a cure system comprising c) a suitable catalyst and where required d) a suitable cross-linker adapted to react with component (a), catalysed with component (c); and either or both of components B. and C. wherein: —B. is one or more hot melt resins; and C. is one or more waxes having a melt temperature of between 40 and 200° C.; and/or an organic resin having a viscosity average molecular weight of from 200 to 6000 and a softening point of from 0° C. and 150° C.; wherein the total amount of components B and/or C in the composition is from 2 to 60% by weight of the whole composition.
July 4, 2006
Date of Patent:
January 3, 2012
Dow Corning Europe SA, Dow Corning GmbH
Edouard Joseph, Patrick Vandereecken, Giuseppina Conti, Robert Bonny
Abstract: A protective coating composition comprising a silicate, such as an organosilicate, an organosilicate polymer and colloidal silica and an organic titanate, preferably a titanate chelate or a titanate ester in a suitable organic solvent. The composition is free from metal particles.
Abstract: The specification describes and claims room temperature vulcanisable compositions formed by mixing components comprising a polysiloxane having hydroxyl or hydrolysable groups, a crosslinker having silicon bonded hydrolysable groups selected from the group consisting of alkoxy-, acetoxy- and oximo and a hydroxy terminated urethane prepolymer with no residual isocyanate groups formed from a polyol and an isocyanate. The compositions demonstrate improved adhesion, thixotropy and toolability.
Abstract: Hydrosilylation reaction curable organosiloxane compositions containing a scavenger for radicals that participate in the free radical polymerization of styrene monomers, which yield upon cure a silicone elastomers having extended moldlife.
Abstract: The specification describes and claims an insulating glass unit and a process for making. The unit comprises two glass panes spaced apart by a spacer of thermoplastics material adherent to the panes, an inert or heavy gas trapped within the unit and a layer of silicone elastomer located at the periphery of the unit between edge portions of the glass panes and in contact with external surfaces of the spacer. The thermoplastics material has a water vapor permeability of not more than about 0.2 l/m2/day (measured at 20° C. for 4 mm thickness) and a shear strength of more than 0.2 MPa as determined at a sealant thickness of 0.5 mm at 23° C. and a shear speed of 100 mm/min.
Abstract: A polymer composition comprises a polymer matrix and a siloxane-containing additive which is substantially incompatible with the polymer matrix, wherein the siloxane of the additive has a hydroxy, alkoxy or epoxy functionality, and a functionality which is capable of bonding with a silicone elastomer-forming composition which is curable by a hydrosilylation reaction. The polymer matrix preferably comprises polyphenylenesulphide, and the additive preferably comprises hydroxy-terminated methylvinyl siloxane. The composition is capable of forming plastics articles to which cured silicone elastomers can adhere.
June 30, 1999
Date of Patent:
March 27, 2001
Dow Corning GmbH
Ernst Gerlach, Edouard Joseph, Klaus Kunz, Dieter Zaulig
Abstract: This invention relates to the preparation of an addition curable composition having self adhesion to substrates. The addition curable composition comprises an organic polymer having on average at least 1.4 alkenyl groups per molecule, a crosslinker having on average at least 1.4 hydrosilyl groups per molecule, a platinum group metal containing catalyst, an alkoxy silicon compound and a titanium compound having Ti--O--C bonds. Another embodiment of this invention is a method of adhering the addition curable composition to a substrate surface.
Abstract: Siloxane-based elastomer-forming compositions comprise a first a,w-dihydroxyl polydiorganosiloxane, a second a,w-dihydroxyl polydiorganosiloxane, a third a,w-dihydroxyl polydiorganosiloxane, an organosilicon compound having at least three silicon-bonded substituents selected from the group consisting of hydrogen and alkoxy groups, and a condensation catalyst. The number average molecular weight ratio of the first a,w-dihydroxyl polydiorganosiloxane to the second a,w-dihydroxyl polydiorganosiloxane is in the range of 20 to 80 and the number average molecular weight ratio of second a,w-dihydroxyl polydiorganosiloxane to the third a,w-dihydroxyl polydiorganosiloxane is in the range of 1 to 6. The molar ratio of the first a,w-dihydroxyl polydiorganosiloxane to the second a,w-dihydroxyl polydiorganosiloxane is in the range of 0.01 to 0.15 and the molar ratio of the second a,w-dihydroxyl polydiorganosiloxane to the third a,w-dihydroxyl polydiorganosiloxane is in the range of 0.2 to 2.
Abstract: This invention relates to the preparation of an addition curable composition curable to a high tensile strength, tack free composition. The addition curable composition comprises an organic polymer having on average at least 1.4 alkenyl groups per molecule, a crosslinker having on average at least 1.4 hydrosilyl groups per molecule, a platinum group metal-containing catalyst and a specific ratio of a fatty acid treated, precipitated calcium carbonate filler having an average particle size in the range of 0.05 to 1 micron and a ground filler selected from the group consisting of calcium carbonate, kaolin clay and amorphous, non quartz silica each having an average particle size in the range of 0.2 to 40 microns.
Abstract: A curable composition which contains a siloxane polymer, filler and a curing agent which is capable of effecting the cure when heated, wherein the curing agent comprises a 1,1 di(tertiary butylperoxy) 3,3,5-trimethylcyclohexane in combination with peroxide selected from the group consisting of dicumyl peroxide and 2,5-di(tertiary butylperoxy) hexane. Also disclosed is a method of providing a molding using said curable composition.
Abstract: This application is concerned with room temperature vulcanizing compositions useful as mould making materials which are formed by mixing an alpha, omega dihydroxy polysiloxane, a condensation polydimethylsiloxane, catalyst and a crosslinking agent which comprises a tri- or tetra-alkoxy silane or siloxane in which the alkoxy groups contain more than two carbon atoms. Moulds made with these materials on epoxy masters show improved usage; the improvement is related to the size of the alkoxy "leaving group" and the proportion of crosslinker and condensation catalyst.
Abstract: A solid lubricant composition comprises (I) 30 to 70 parts by weight of graphite, (II) 70 to 30 parts by weight of a mixture of at least two components selected from alkali molybdate, alkali or alkaline earth sulphate and alkali phosphate, the ratio of the two individual ingredients being in the range of from 0.05/1 to 20/1. Compositions give improved load-bearing capacity and allows settling of friction coefficient.
Abstract: An elastomer-forming silicone composition comprising (A) a vinyl-organopolysiloxane, (B) an organosilicon compound, (C) a noble metal catalyst and (D) an adhesion promoter characterised in that the adhesion promotor is the product of the mixture or reaction of (1) an organosiloxane compound having at least two trialkoxysilyl groups, (2) an unsaturated alcohol having at least one .alpha.,.beta.-unsaturated alkenyl group and has improved adhesion without the toxic disadvantages of the prior art.
Abstract: A dispensing cartridge, suitable for sealant sausages in use with mechanical and pneumatic sealant applicator guns, comprises a sleeve, a detachable end cap with releasable nozzle and a plunger. The plunger has offsets on its leading and trailing edges, which are the only portions which form a seal with the interior surface of the sleeve. Preferably the support portion of the plunger is bi-concave and the sleeve adapted to receive the end cap on either end. This renders the cartridge bi-directional, allowing loading of sausages and extrusion at either end.
Abstract: A foam forming composition comprises (a) one or more polysiloxanes having not less than three alkylhydrogen siloxane units per molecule, (b) one or more polysiloxanes having not less than two silicon-bonded hydroxyl group per molecule, (c) at least one liquid organic titanium compound and (d) a catalyst. Reaction between the organic titanate (e.g. tetraisopropyltitanate) and the hydroxy functional polysiloxane rapidly increases viscosity of the mixture to restrict flow of the composition as it cures to form a foam within 240 seconds of mixing. A vinyl polysiloxane may be incorporated.
Abstract: This invention discloses elastomer-forming compositions which have a low viscosity in the uncured state while retaining good physical properties when cured. They comprise an .alpha.,.omega. hydroxyl, trialkoxy or alkylenetrialkoxy end-blocked polydiorganosiloxane, a MQ silicone resin having tetrafunctional units of the formula SiO.sub.2 and monovalent units of the formula R.sub.a R'.sub.3-a SiO.sub.1/2 wherein R' denotes a group of the general formula --R"Si(OR.sup.*).sub.3, with R" being an alkylene group and R.sup.* an alkyl group and wherein a has a value of 2 or 3, preferably 2 for up to 30% of all monovalent units and a titanium catalyst.
Abstract: The specification describes and claims a composition curable to an elastomer in the presence of moisture and characterized in that it comprises the product obtained by mixing (A) 100 parts by weight of a polydiorganosiloxane having at least two silicon-bonded hydroxyl groups and wherein at least 50 percent of the total organic substituents are methyl groups, (e.g. according to the genertal formula H(OSiR".sub.2).sub.x OH wherein substantially all of the groups R" are methyl groups and x is an integer having an average value from 250 to 1500), (B) from 1 to 40 parts by weight of one or more oxime silanes of the general formulaR.sub.4-n Si(ON.dbd.CR'.sub.2).sub.nwherein each R represents an alkyl group having less than 6 carbon atoms, a vinyl group, an allyl group or a phenyl group, each R' represents an alkyl group having from 1 to 6 carbon atoms or a phenyl group and n has an average value of from 2.1 to 3 and (C) from 0.1 to 1.
Abstract: A lubricant for water fittings is described which essentially consists of a natural or synthetic high viscosity lubricating oil or lubricating grease, possibly an organic or inorganic thickener, and an additive in the form of at least one complexing agent and possibly at least one hydrophobing agent. Compared to known lubricants for water fittings, said lubricant is characterized by a performance capability which lasts substantially longer since the formation of disturbing deposits, particularly in the form of lime and rust, is greatly inhibited with said lubricant. The water fittings lubricated with this lubricant therefore remain functional substantially longer.
Abstract: A high temperature screw lubricating paste is described which consists essentially of finely divided tin dioxide and, optionally, a thermally stable inorganic filler homogeneously dispersed in a carrier oil. The inert paste may be used with threaded connections to provide a low break-away torque when the connections are exposed to high temperatures for extended periods.
Abstract: A solid lubricant combination comprising (a) 25 to 65 parts by weight graphite, (b) 15 to 45 parts by weight zinc sulfide, (c) 5 to 20 parts by weight antimony (III) sulfide, and (d) 5 to 20 parts by weight of an alkali earth metal phosphate, or other inorganic metal phosphate or mixtures of such phosphates which are commonly known as solid lubricants, is described. The solid lubricant combination is especially suitable as an additive to friction linings and results in an improvement in their tribological properties.