Abstract: Linear organopolysiloxanes of the structure M-(T-M)n-M are prepared by reaction of lithium and/or sodium silanolates with chlorosilanes. The products contain at least two groups selected from silicon-bonded hydrogen and aliphatically unsaturated groups.

Abstract: An organosilicon compound having diphenylethyl and methoxysilyl groups is more readily hydrolyzable than ethoxysilyl-containing organosilicon compounds and generates no hydrogen chloride on use.

Abstract: Methods of synthesis and application thereof for peripherally aromatic silsesquioxanes featuring reactive functionality. A method, according to one embodiment of the invention, includes reacting a polyhedral oligomeric silsesquioxane with an anhydride. The polyhedral oligomeric silsesquioxane has an inorganic core, a phenyl moiety or an anlyine moiety covalently coupled to the at least one T-type silicon atom; and a metal-aniline group or a para-aniline group covalently coupled to the at least one D-type or M-type silicon atom. The inorganic core includes 6-14 silicon atoms, at least one of the silicon atoms being an M-type silicon atom or a D-type silicon atom, and at least one of the silicon atoms being a T-type silicon atom, and 9-20 oxygen atoms.

Abstract: Novel POSS mono- and dianiline compounds, their synthesis procedures, and applications in host materials for the purposes of property enhancement are described. This class of POSS compounds features completely aromatic peripheries and partial amine functionality for facile and controlled reactive incorporation into a variety of polymers, and further utility may be derived from reactions of the available amine groups with anhydrides such as phenylethynyl phthalic anhydride (PEPA) to form reactive imide-type oligomers for incorporation into high performance thermosetting polymers. Modification of polymer hosts with the subject nanoparticles can result in a variety of property improvements including mechanical, thermal, tribological, electrical, as well as improved moisture resistance.

Abstract: A composition containing a metal compound and a siloxane compound (A) represented by general formula (1): wherein X is represented by general formula X1 or X2: wherein the number of X1 is 1-8; the number of X2 is 0-7; the sum of the number of X1 and the number of X2 is 8; R1 to R4 represent a hydrogen atom, a C1-8 alkyl group, alkenyl group, alkynyl group, or a C6-8 aryl group, a hydrogen atom thereof optionally being substituted by a fluorine atom; R5 represents a C1-18 alkyl group, alkenyl group, alkynyl group or aryl group, a hydrogen atom thereof being optionally substituted by a fluorine atom, a carbon atom being optionally substituted by an oxygen atom or a nitrogen atom; R6 represents a hydrogen atom, a vinyl group or an allyl group; m and n represent an integer of 1-4; and 3?m+n.

Abstract: The present invention provides a fluorescent dye-silane hybrid resin manufactured by polycondensing an alkoxysilane bonded with a fluorescent dye with an organo-silane. More particularly, the present invention provides a fluorescent dye-siloxane hybrid resin that is manufactured by reacting a fluorescent dye having one or more functional groups with an alkoxysilane having an organic functional group to form an alkoxysilane bonded with the fluorescent dye and then polycondensing the alkoxysilane bonded with a fluorescent dye with an organo-silanediol and an organo-alkoxysilane having a thermocurable or ultraviolet-curable functional group without water. The fluorescent dye-silane hybrid resin has excellent thermostability, photostability, fluorescence characteristics, and processibility.

Abstract: The invention relates to emulsifiers comprising glycerin-modified organopolysiloxanes and to their use for the preparation of extraordinarily stable emulsions and dispersions.

Abstract: A siloxane compound according to the present invention is represented by the general formula (1). wherein X are each independently either X1 or X2 with the proviso that at least one of X is X2; R1 to R5 are each independently a hydrogen atom, a C1-C8 alkyl, alkenyl or alkynyl group, a phenyl group or a pyridyl group; each of R1 to R5 may have a carbon atom replaced by an oxygen atom and may have an ether bond, a carbonyl group or an ester bond in its structure; m and n are each independently an integer of 1 to 10; and Y are each independently a specific cross-linking group. The siloxane compound according to the present invention has flowability and easy formability at lower temperatures as compared to conventional silsesquioxanes.

Abstract: Various apparatuses, systems and methods involve high mobility materials. In accordance with one or more example embodiments, a material includes a conjugated molecule and a side chain bonded to the conjugated molecule. The side chain includes at least one of a siloxane-terminated unit and a derivative of a siloxane-terminated unit that enhance solubility of the conjugated molecule. Further, the side chain facilitates a ?-stacking distance between the conjugated molecules when stacked (e.g.

Abstract: The invention relates to allyl functionalized precipitated silica, rubber compositions containing such silica, particularly sulfur cured rubber compositions, and articles of manufacture having a component thereof such as, for example tires. The invention particularly relates to synthetic amorphous silica, particularly a precipitated silica, treated with an allyl silane, particularly to a precipitated silica containing allyl functional groups.

Abstract: Hydrophobic silica particles are produced by reacting them with a hydrosiloxane agent.

Abstract: This invention relates to an absorbent including trimethylsilylated mesoporous silica SBA-15, and more particularly to an absorbent including trimethylsilylated mesoporous silica SBA-15, which can effectively remove 90% or more of the seven pharmaceuticals of carbamazepine, diclofenac, estrone, gemfibrozil, ibuprofen, ketoprofen, and trimethoprim which are present in high concentration.

Abstract: The invention relates to a hydrophobic fumed silica which is obtained by grinding a fumed silica which, as a result of silanization, has trimethylsilyl groups fixed on the surface; and to coating formulations comprising this silica.

Abstract: A hydrolyzable group-containing organosilicon compound is represented by the general formula XCH2Si(OSiYR22)nR13-n??(1) wherein each R1 is independently a C1-20 hydrolyzable group; each R2 is independently a C1-20 substituted or unsubstituted monovalent hydrocarbyl group excluding groups that have an aliphatically unsaturated bond; X is a halogen atom; Y is the hydrogen atom or a C2-18 alkenyl group; and n is 1 or 2. The organosilicon compound of the present invention can efficiently introduce a hydrolysable group into various compounds through the hydrosilylation reaction.

Abstract: The invention relates to allyl functionalized precipitated silica, rubber compositions containing such silica, particularly sulfur cured rubber compositions, and articles of manufacture having a component thereof such as, for example tires. The invention particularly relates to synthetic amorphous silica, particularly a precipitated silica, treated with an allyl silane, particularly to a precipitated silica containing allyl functional groups.

Abstract: A highly crosslinked polysiloxane dye comprising at least 10 Si atoms, including at least one moiety of the formula (I) whose open Si-bonds each are linked to an oxygen atom and open O-bond is linked to a silicon atom in the rest of the polysiloxane, and wherein T is a direct bond or an organic spacer group such as C1-C18alkylene, C2-C12alkenylene, C5-C10cycloalkylene, C5-C10arylene, —C5-C10arylene-(C1-C10alkylene)- each of which may be end-capped towards the linkage to Dye by CO, COO, NR1, CONR1, NR1CONR1, CS, CSS, CSNR1, NR1CSNR1, O, S, SO, SO2, C5-C10cycloalkylene, C5-C10arylene; or T is C3-C18alkylene interrupted, and optionally end-capped towards the linkage to Dye, by CO, COO, NR1, CONR1, NR1CONR1, CS, CSS, CSNR1, NR1CSNR1, O, S, SO, —SO2—, C5-C10cycloalkylene, C5-C10arylene; or is CO; (CH2CH2—O)1-5; COO; N(R1); CON(R1); O; S; SO; SO2; R1 is hydrogen; unsubstituted or substituted, straight-chain or branched, monocyclic or polycyclic, interrupted or uninterrupted C1-C14alkyl; C2-C14alkenyl; C6-C10aryl; C

Abstract: The invention relates to allyl functionalized precipitated silica, rubber compositions containing such silica, particularly sulfur cured rubber compositions, and articles of manufacture having a component thereof such as, for example tires. The invention particularly relates to synthetic amorphous silica, particularly a precipitated silica, treated with an allyl silane, particularly to a precipitated silica containing allyl functional groups.

Abstract: A continuous process for the preparation of organopolysiloxanes involves, in a first step, reacting chlorosilanes with from 0.01 to 0.7 mol of water per mole of hydrolyzable chlorine and with from 0.2 to 1.7 mol of alcohol per mole of hydrolyzable chlorine, the molar ratio of water to alcohol being from 0.005 to 3.5; in a second step, the reaction mixture obtained in the first step is optionally mixed continuously with a water-insoluble organic solvent having a density of less than 0.9 kg/l, and water is metered in continuously in amounts of from 0.2 to 100 mol of water per mole of silicon component; and in a third step, the aqueous alcoholic phase is separated off.

Abstract: Polymers are described that are prepared from di and mono-functional silicone and silane monomers of Formula 1 in which Y represents a direct bond or a oxy group; R1 represents an optionally substituted organo group with at least one double bond which optionally may be an activated unsaturated moiety such as a (meth)acrylate group: for example 1-n-propoxy(acrylate) or ethenyl; and R2 and R3 each separately, and independently within each optional repeat unit, represent an optionally substituted hydrocarbo, hydrocarbo(oxy), hydrosilico and/or hydrosilico(oxy) groups; or example, methyl; or trimethylsiloxy; R4 independently represents an optionally substituted organo group with at least one double bond (such as R1 above) an optionally substituted hydrocarbo, and/or hydrosilico group for example trimethylsilyl or ethenyl; and n is from about 0 to about 2000; preferably from about 1 to about 100, for example n is 1.

Abstract: The present inventors have obtained a PSQ derivative of a completely condensed type into which a functional group is readily introduced by using a novel PSQ derivative of an incompletely condensed type in which four alkaline metal atoms are bonded to silsesquioxane of a cage type having eight Si's. The above silsesquioxane derivative is represented by Formula (1). A silsesquioxane derivative to which alkaline metal atoms are bonded is represented by Formula (2). In Formula (1) and Formula (2), R is a group selected from alkyl, aryl and arylalkyl; Y is a group represented by Formula (a) or Formula (b); and M is a monovalent alkaline metal atom. X in Formula (a) and Formula (b) is hydrogen, halogen, a hydroxyl group or a monovalent organic group, and Z is —O—, —CH2— or a single bond. The preferred organic group is a functional group or a group having a functional group.

Abstract: A polymer having a repeating unit represented by formula (I) is used for an insulating-film forming material and an insulating film. wherein R1 to R7 each are a monovalent hydrocarbon group, etc.; one of X, Y and Z is a specific siloxane group and the remaining two each are —O— or divalent silyl-containing group that bonds to (I) on the side of the oxygen atom of the group.

Abstract: Polymerizable silicon-containing compounds of formula (1) wherein R1 is hydrogen, halogen or monovalent organic group are polymerized into polymers.

Abstract: The present inventors have obtained a PSQ derivative of a completely condensed type into which a functional group is readily introduced by using a novel PSQ derivative of an incompletely condensed type in which four alkaline metal atoms are bonded to silsesquioxane of a cage type having eight Si's. The above silsesquioxane derivative is represented by Formula (1). A silsesquioxane derivative to which alkaline metal atoms are bonded is represented by Formula (2). In Formula (1) and Formula (2), R is a group selected from alkyl, aryl and arylalkyl; Y is a group represented by Formula (a) or Formula (b); and M is a monovalent alkaline metal atom. X in Formula (a) and Formula (b) is hydrogen, halogen, a hydroxyl group or a monovalent organic group, and Z is —O—, —CH2— or a single bond. The preferred organic group is a functional group or a group having a functional group.

Abstract: Three processes for the manufacture of polyhedral oligomeric silsesquioxanes (POSS) which utilize the action of bases that are capable of either attacking silicon or any compound that can react with a protic solvent (e.g. ROH, H2O etc.) and generate hydroxide [OH]?, alkoxide [RO]??, etc. The first process utilizes such bases to effectively redistribute the silicon-oxygen frameworks in polymeric silsesquioxanes [RSiO1.5]28 where ?=1-1,000,000 or higher into POSS nanostructures of formulas [(RSiO1.5)n?#, homoleptic, [(RXSiO1.5)n]?#, functionalized homoleptic, [(RSiO1.5)m(R?SiO1.5)n]?#, heteroleptic, and {(RSiO1.5)m(RXSiO1.0)n}?#, functionalized heteroleptic nanostructures. The second process utilizes base to aid in the formation of POSS nanostructures of formulas [(RSiO1.5)n]?# homoleptic and [(RSiO1.5)m(R?SiO1.5)n]?# heteroleptic and [(RSiO1.5)m(RXSiO1.

Abstract: The method for producing polyorganosiloxane from at least one type of organosilicon compound having a siloxane unit or alkoxysilane by the equilibrating reaction involving cleavage and recombination of the silicon-oxygen bond as a method carried out in the presence of an acidic catalyst capable of giving the product in high productivity and yield, corrosive to the system to a limited extent, and remaining in the product to a limited extent or degrading product quality to a limited extent if it remains, wherein a solid, acidic zirconium oxide catalyst is used as the acidic catalyst.

Abstract: By reacting a branched siloxane compound of formula (2) containing compounds of formula (1) as an impurity with a disiloxane compound of formula (3) in the presence of an acid compound, there is prepared a branched siloxane of formula (2) containing a reduced level of compounds of formula (1). R1nSi(OSiR23)3-n(OR3)??(1) R1nSi(OSiR23)4-n??(2) R23SiOSiR23??(3) R1 is a monovalent hydrocarbon group, R2 and R3 are H or monovalent hydrocarbon groups, and n is 0 or 1.

Abstract: In order to provide a relining for prosthesis and a process for the manufacturing thereof with improving the performance of the relining and the application-technical characteristics of the individual components as compared with the state of the art, it is proposed to prepare the relining from a one-component relining adhesive, a two-component relining silicone and optionally a two-component sealing lacquer.

Abstract: A silicone emulsion composition of the addition reaction curing type comprising a major proportion of an organopolysiloxane containing at least two alkenyl radicals and T units and having a viscosity of 5-100 mPa·s, a minor proportion of another organopolysiloxane containing at least two alkenyl radicals and having a 30% toluene diluted viscosity of 1,000-10,000 mPa·s, an organohydrogenpolysiloxane, a platinum radical metal catalyst, a surfactant, and water cures into a coating that adheres well to plastic film substrates. The cured coating exhibits release properties to pressure-sensitive adhesives and can be utilized as release film.

Abstract: Provided are polyorganosilsesquioxane and process for preparing the same. The polyorganosilsesquioxane is obtained by various methods including polymerization of an organosilanetriol as starting materials. The polyorganosilsesquioxane has convenience in handling and controlling the rate of polymerization, and structure of highly regular form, and be imparted high functionality and various characteristics as compared to a conventional polyorganosilsesquioxane.

Abstract: The present invention relates to a silicon-containing liquid composition comprising (A) 100 parts by weight of an organosilicate, calculated as SiO2, (B) 0.1 to 10 parts by weight of a catalyst, (C) 100 to 50,000 parts by weight of water, and (D) 100 to 50,000 parts by weight of a solvent, a weight ratio of the water (C) to the solvent (D) being in the range of 30:70 to 80:20.

Abstract: A low molecular weight branched siloxane, typically methyltris(trimethylsiloxy)silane is effectively prepared in high yields by reacting a trichlorosilane, typically methyltrichlorosilane with a disiloxane, typically hexamethyldisiloxane in the presence of a linear phosphonitrilic chloride (LPNC) catalyst.

Abstract: It is here intended to provide a modified silicone compound having excellent heat-resistant properties and a process of producing the same, and there is disclosed a modified silicone compound having an Si—H bond and an unsaturated bond, represented by the general formula (1): 1

Abstract: A branched organopolysiloxane is prepared by polymerizing an organopolysiloxane mixture of a branch unit-containing organopolysiloxane and a low molecular weight organopolysiloxane in the presence of an acidic or basic catalyst, or by adding a surfactant to the organopolysiloxane mixture, dispersing it in water to form an emulsion, and polymerizing the emulsion.

Abstract: An oligosiloxane having the formula (R1O)aSi(OSiR22R3)4−a wherein R1 is alkyl; each R2 is independently selected from C1 to C10 monovalent hydrocarbyl free of aliphatic unsaturation; R3 is hydrocarbly free of aliphatic unsaturation and having at least 11 carbon atoms; and a is 1, 2, or 3; and a method of preparing an alkoxy-functional oligosiloxane.

Abstract: This invention relates to silicone compounds in which terminal SiO of cage-type and/or ladder-type polyphenylsilsesquioxanes is wholly or partly linked to a triorganosilyl group containing reactive functional group X and also relates to a process for preparing said silicone compounds by subjecting cage-terminated and silanol-free cage-type and/or ladder-type polyphenylsilsesquioxanes to an equilibrium reaction under heat with disiloxanes containing reactive functional group X of the following structural formula in an organic solvent in the presence of an alkaline rearrangement and condensation catalyst. This invention provides silicone compounds containing terminal reactive functional groups of excellent storage stability and properties of good reproducibility such as heat resistance.

Abstract: A method for manufacturing an organic solvent-soluble hydrogenated octasilsesquioxane-vinyl group-containing compound copolymer comprising reacting 1 mol of (A) a hydrogenated octasilsesquioxane described by formula I with 0.2 to less than 3 mol of (B) a divinyl group-containing compound described by formula (2) CH2═CH—L—CH═CH2   Formula 2 where L is selected from the group consisting of (a) a divalent hydrocarbon group comprising 3 to 10 carbon atoms and (b) —(SiR2O)m—SiR2—, where each R is independently selected from the group consisting of alkyls comprising 1 to 6 carbon atoms and aryls comprising 6 to 9 carbon atoms and 1≦m≦10; in the presence of a hydrosilylation catalyst.

Abstract: A method of producing a branched silicone oil which comprises mixing 100 parts by weight of an organopolysiloxane represented by the following formula (I) and/or an organopolysiloxane represented by the following formula (II) with 0.1 to 100 parts by weight of an organopolysiloxane represented by the following formula (III) and causing these oranopolysiloxanes to undergo condensation and equilibration reactions by heating them in the presence of basic catalysts: wherein R1 and R2 are each a monovalent hydrocarbon group containing 1 to 20 carbon atoms, m is an integer from 3 to 7, and n is an integer of 0 or above; wherein R3 is a monovalent hydrocarbon group containing 1 to 20 carbon atoms, p is a number from 1 to 100, and q is a number from 0 to 100.

Abstract: The present invention discloses a process for producing a polyorganosiloxane, which comprises adding an organochlorosilane to a uniform mixture comprising water and at least one kind of alcohol, to subject the organochlorosilane to a hydrolysis and condensation reaction. The organochlorosilane is preferably one represented by the following formula (1):R.sup.1 --Si(Cl).sub.3 (1)wherein R.sup.1 is a C.sub.1-30 straight chain saturated or unsaturated hydrocarbon group, a C.sub.1-30 branched chain saturated or unsaturated hydrocarbon group, a phenyl group, a cyclohexyl group, a C.sub.3-15 halogenated hydrocarbon group, an acryloxypropyl group or a methacryloxypropyl group.

Abstract: Novel liquid organopolysiloxane resins of the average composition[R.sup.1 Si(CH.sub.3).sub.2 O.sub.1/2 ].sub.a [(CH.sub.3).sub.3 SiO.sub.1/2 ].sub.b [R.sup.2 O.sub.1/2 ].sub.c [R.sup.1 Si(CH.sub.3)O].sub.d [(CH.sub.3).sub.2 SiO].sub.e [SiO.sub.2 ],whereinR.sup.1 is a C.sub.2 -C.sub.8 -alkenyl group,R.sup.2 is an optionally substituted, linear or branched C.sub.1 -C.sub.8 -alkyl group or a mixture thereof,a+b+c+d+e is about 1 to 6,d+e is about 0 to 3,the resin has a viscosity of 0.1 to 1000 Pas at 25.degree. C., andthe alkenyl or vinyl content of the resin is in the range of 0.4 to 4 mmol/g,and their preparation by reacting at least one of tetraalkoxysilane and its partial hydrolyzate with at least one organosiloxane and a strong acid as catalyst in the presence of water and optionally an organic solvent at a temperature of about >40.degree. C. They are formulated into novel low viscosity polydiorganosiloxane compositions.

Abstract: A release agent composition for use in an electrophotographic process is disclosed. This composition includes a specifically-defined heat-stable silicone oil-silicone wax random copolymer. The copolymer has a melting point such that it is liquid on the hot fuser roll, but solidifies at room temperature on the printed page. A random silicone copolymer, in the form of a paste or pliable caulk, which is useful for sealing leaks in toner cartridges is also disclosed. Finally, the method for preparing these copolymers is disclosed.

Abstract: A release agent composition for use in an electrophotographic process is disclosed. This composition includes a specifically-defined heat-stable silicone oil-silicone wax random copolymer. The copolymer has a melting point such that it is liquid on the hot fuser roll, but solidifies at room temperature on the printed page. A random silicone copolymer, in the form of a paste or pliable caulk, which is useful for sealing leaks in toner cartridges is also disclosed. Finally, the method for preparing these copolymers is disclosed.

Abstract: A curable silicone composition based on an organopolysiloxane having a cyclotrisiloxane structure quickly cures by brief heating or ultraviolet exposure. It further contains an acid, acid generator, base or base generator or an oniom salt photo-initiator as a curing agent. The cured product has release property from adhesive substance which remains unchanged with the lapse of time and good mold release properties, and thus provides a lightly releasable cured film. The composition is widely used as adhesive tape backing agents, mold release agents, protective coating agents, water and oil repellent agents, and paint base.

Abstract: A high-molecular weight polyorganosilyl silicate having a weight-average molecular weight of 30,000 to 2,000,000 on polystyrene conversion in which the repeating units form a ladder structure through siloxane bonding, and the ladder structures are further bonded together through siloxane bonding is disclosed. Also disclosed is a process for producing the polymer. The polymer is useful as a coating material or a film-forming material to provide a coating film or a film having excellent electrical characteristics, weather resistance, adhesion, water repellency, processability and scratch resistance.

Abstract: The invention provides high purity branched phenylsilsesquioxane containing fluids of the general formula Me.sub.3 SiO--(Me.sub.3 SiOPhSiO).sub.x --SiMe.sub.3, wherein Me is methyl, Ph is phenyl, and x is 1 to 6, and an essentially zero waste process for their synthesis in quantitative yield.

Abstract: A process of producing an organopolysiloxane, comprising hydrolyzing and condensing an alkoxysilane having the formula:R.sub.m Si(OR.sup.1).sub.4-mwherein R is a monovalent hydrocarbon group, R.sup.1 is an alkyl group and m is an integer of 0 to 3, or a partial hydrolysis-condensation product thereof, in the presence of a fluorine compound selected from the group consisting of fluoride salt compounds and fluorine-containing silicon compounds having at least one Si-F bond in its molecule. The organopolysiloxane obtained contains little silanol groups and has a narrow molecular weight distribution. Therefore, curable silicone resin compositions containing the organopolysiloxane as a raw material have good shelf stability, drying characteristics and curability, and are free of fear of catching fire or contamination of surroundings. An organopolysiloxane having a variety of functional groups can be readily produced.

Abstract: A synthesis process for polysilsesquioxanes which produces a high yield, tractable copolymer of perfectly alternating silsesquioxane and bridging group segments is provided. A difunctional silsesquioxane monomer of the formula Si.sub.8 R.sub.8 O.sub.11 (OA).sub.2 or Si.sub.7 R.sub.7 O.sub.9 (OSiR.sup.4 R.sup.5 R.sup.6) (OA).sub.2 is reacted with a difunctional compound of the formula X-M-X which forms a bridging group for a time sufficient to condense the difunctional silsesquioxane monomers and bridging groups into a linear polymer containing alternating silsesquioxane and bridging group segments. The resulting linear copolymer is essentially free of impurities and has controllable properties through the proper selection of the monomeric starting materials.

Abstract: Novel organopolysiloxanes having one silanol group within a molecule and the method for manufacturing them at high purity and high yield. The organopolysiloxanes having a silanol group are expressed by the formula (1) below: ##STR1## wherein R.sup.1 is a monovalent hydrocarbon group with 1 to 8 carbon atoms, each of R.sup.2, R.sup.3 and R.sup.4 is a monovalent hydrocarbon group with 1 to 8 carbon atoms or a siloxyl group expressed by --OSiR.sup.5 R.sup.7, wherein R.sup.5, R.sup.6 and R.sup.7 are monovalent hydrocarbon groups with 1 to 8 carbon atoms, Y is either a hydrogen atom, a halogen atom, or a monovalent hydrocarbon group with 1 to 12 carbon atoms, n is an integer of from 0 to 12, and a is either 0 or 1, with the proviso that the grouping Y--(CH.sub.2).sub.n --Si does not includes H--Si, CH.sub.3 --Si or a hydrolyzable silyl group.

Abstract: A process for preparation of reactive polyhedral oligomeric silsesquioxanes and the subsequent synthesis of polysilsesquioxanes which produce high yield, tractable polymers containing silsesquioxane segments is provided. A trifunctional polyhedral oligomeric silsesquioxane of the formula Si.sub.7 R.sub.7 O.sub.9 (OA).sub.3 is corner capped by reacting it with a compound of the formula M-Z to form a polyhedral oligomeric silsesquioxane which can be reacted in various ways with oligomers, polymers, catalysts, or co-monomers to form polyhedral silsesquioxane polymers containing silsesquioxanes as pendant, block, or end group segments. The resulting polymers are essentially free of impurities and have controllable properties through the proper selection of the synthesis process and starting materials.

Abstract: An alkoxysilane is brought into a hydrolysis-polycondensation reaction using a fluoride salt, e.g. NaF, or a fluorine-containing silicon compound having an Si--F bond in its molecule, e.g. FSi(OCH.sub.3).sub.3, as a catalyst, to produce a powder of a silicon compound such as silica. The process reduces markedly the period of time required for the hydrolysis-polycondensation reaction and yields a porous silicon compound powder with low bulk specific gravity. The catalyst is excellent in handleability and safety.

Abstract: The present invention relates to a new silicone cure system. More particularly, the present invention discloses that a siloxane system containing sufficiently high levels of T or Q species in addition to M, D and a limited amount of silanol species can be cured by linear phosphonitrilic chloride disproportionation catalyst.