Abstract: The present invention relates to a composition for a thermoplastic silicone resin, the composition including: an alkenyl-containing cage octasilsesquioxane represented by formula (I) in which R1 represents a substituted or unsubstituted alkenyl group, R2 represents a monovalent hydrocarbon group, and all R2 groups may be the same or different; an organohydrogensiloxane; and a hydrosilylation catalyst.

Abstract: A curable composition which comprises at least one of the following (A), (B), and (C) and further contains (D) (provided that when (C) is not contained, both (A) and (B) are in the composition. (A): A silicon-containing polymer in which the content of components having a weight-average molecular weight of 1,000 or lower is 20 wt. % or lower and which has a reactive group A? and one or more Si—O—Si bonds. (B): A silicon-containing polymer in which the content of components having a weight-average molecular weight of 1,000 or lower is 20 wt. % or lower and which has an Si—H group and one or more Si—O—Si bonds. (C): A silicon-containing polymer in which the content of components having a weight-average molecular weight of 1,000 or lower is 20 wt. % or lower and which has a reactive group A?, an Si—H group, and one or more Si—O—Si bonds. (D): A catalyst for curing reaction which is a platinum catalyst.

Abstract: An aqueous polyorganosiloxane (POS) emulsion which can easily be deposited on/applied to a fibrous substrate at high speed and at limited deposition rates, for example less than 40 g/m2. The emulsion contains (A) a POS with ?Si-vinyl units, (B) a POS with ?SiH units, (C) an adhesion promoter, (D) a catalyst, (E) at least one surfactant, (F) optionally a POS resin with ?Si-vinyl units, (G) optionally a crosslinking inhibitor, (H) optionally a pH fixing agent, (I) optionally a formulating additive, (J) optionally a filler, and (K) water. Adhesion promoter (C) is selected from protective hydrocolloids, hydroxylated silanes and/or POS carrying at least one hydroxyl group and at least one salified amino group per molecule, and mixtures thereof, and is present in the range from 0.005 to 10% by weight, based on the silicone phase. Also disclosed is the corresponding coating process and the coated substrate.

Abstract: A thermosetting resin compositing having an essential component (A) organopolysiloxane containing a compound represented by following general formula (1) or (2) and optical semiconductor peripheral material using the composition. [Herein, in the formulas, R1 independently represents a substituted or non-substituted monovalent hydrocarbon radical with the carbon number of 1 to 10, R2 represents an epoxy group-containing organic group, R3 represents R1 or R2, a independently represents an integer of 2 or more, b independently represents an integer of 0 or more, X represents general formula (3), Y represents -o- or a bivalent hydrocarbon radical with the carbon number of 1 to 6, Z represents following formula (4), R1 in the formula independently represents a substituted or non-substituted monovalent hydrocarbon radical with the carbon number of 1 to 10, and c represents an integer of 0 or more.

Abstract: A method to reduce liquid polymer macromolecule mobility through forming a polymer blend system is provided. More particularly, a small amount of polymer crosslinker is added to a liquid polymer matrix to prevent intermolecular movement. The crosslinker functions as cages to block linear or branched linear macromolecules and prevent them from sliding into each other.

Abstract: The present invention provides a triblock copolymer and a viscoelastic biostable foam comprising the same.

Abstract: A method of manufacturing an analytical sample by a secondary ion mass spectrometry method is provided, which comprises a step of forming a separation layer over a substrate, a step of forming one of a thin film and a thin-film stack body to be analyzed over the separation layer, a step of forming an opening portion in one of the thin film and the thin-film stack body, a step of attaching a supporting body to one of a surface of the thin film and a surface of a top layer of the thin-film stack body, and a step of separating one of the thin film and the thin-film stack body from the substrate.

Abstract: Inorganic/organic hybrid polymers containing silsesquioxane cages are robust and exhibit desirable physical properties such as strength, hardness, and optical transparency at infrared and ultraviolet wavelengths. The polymers are prepared by polymerizing functionalized polyhedral silsesquioxane monomers such as polyhedral silsesquioxanes bearing two complementarily reactive functional groups bonded to cage silicon atoms by means of spacer moieties. The spacer moieties allow for steric mobility and more complete cure than polyhedral silsesquioxanes bearing reactive functional groups bound directly to cage silicon atoms.

Abstract: A method for easily producing high-purity polydimethylsilane or polydiphenylsilane, where by-products such as alkali metal salt and alkaline earth metal salt can be efficiently removed, is provided. Dimethyldichlorosilane or diphenyldichlorosilane is reacted with an alkali metal such as metal sodium and metal magnesium and/or an alkaline earth metal in an organic solvent such as toluene to obtain crude polydimethylsilane or crude polydiphenylsilane, methanol having dissolved therein an ether ester-type nonionic surfactant or a surfactant such as alkylbenzenesulfonate is added to the crude polydimethylsilane or the crude polydiphenylsilane to deactivate the remaining alkali metal and alkaline earth metal, and the crude polydimethylsilane or the crude polydiphenylsilane is washed with water in the presence of a surfactant to efficiently remove an alkali metal salt, an alkaline earth metal salt and the like, whereby high-purity polydimethylsilane or polydiphenylsilane is obtained.

Abstract: Disclosed are a curable composition characterized by using a curable composition including an organic polymer (A1) having one or more silicon-containing functional groups capable of cross-linking by forming siloxane bonds in which the one or more silicon-containing functional groups capable of cross-linking by forming siloxane bonds are silicon-containing functional groups each having three or more hydrolyzable groups on one or more silicon atoms thereof; and a method for controlling the recovery properties, durability and creep resistance of the cured article. Herewith, the present invention provides a curable composition capable of giving a cured article excellent in recovery properties, durability and creep resistance, and a method for controlling the recovery properties, durability and creep resistance of the cured article.

Abstract: The present invention relates to novel sunscreens on the basis of polysiloxanes, to their preparation and to their use, especially in formulations for the protection against harmful effects of sunlight.

Abstract: A composition containing (A) a compound having at least one aliphatic unsaturation; (B) a cyclic organohydrogen-silicon crosslinking compound containing at least one silicon-bonded hydrogen atom (Sift) per molecule, prepared by a platinum catalyzed coupling reaction of a methylhydrogen cyclosiloxane, with a reactant containing aliphatic unsaturation, hydroxy functionalities, or a mixture of both; and (B1) a linear or branched acyclic organohydrogensilicon Crosslinking compound containing at least one silicon-bonded hydrogen atom per molecule. The composition can be used to prepare release coating compositions by adding (C) a platinum group metal-containing catalyst. Release coating compositions containing Components (B) and (B1) have better cure, better adhesion, and lower release forces, than release coating compositions containing only Component (B).

Abstract: Disclosed herein is a composition comprising a structure (M1)a(ME)b(D1)c(D2)d(T)e(Q)f, wherein M1=R1R2R3SiO1/2; ME=R4R5RESiO1/2; D1=R6R7SiO2/2; D2=R8R9SiO2/2; T=R10SiO3/2; and Q=SiO4/2; wherein each RE is independently a monovalent hydrocarbon radical containing an epoxy group; R9 comprises a structure -L1-Si(R11)g(OR12)3-g or L2(D3)h(M2)i-L3-Si(R13)g?(OR14)3-g?, wherein L1, L2, and L3 are independently divalent linking groups; g and g? independently have a value from 0 to 2; M2=R15R16R17SiO1/2; D3=R18R19SiO2/2; wherein R1, R2, R3, R4, R5, R6, R7, R8, R10, R11, R12, R13, R14, R15, R16, R17, R18, and R19 are independently monovalent hydrocarbon radicals; wherein a, b, c, d, e, f, h, and i are stoichiometric subscripts that are zero or positive subject to the following limitations: b has a value of 2; d is greater than or equal to 1; when (a+c+e+f) is equal to zero, (b+d) is greater than or equal to 3; and when i=0, h is at least 1.

Abstract: A composition that includes functionalized polyhedral oligomeric silsesquioxanes derivatives of the formulas TmR3 where m is equal to 8, 10 or 12 and QnMnR1,R2,R3 where n is equal to 8, 10 or 12 are provided. The functional groups include aqueous base soluble moieties. Mixtures of the functionalized polyhedral oligomeric silsesquioxanes derivatives are highly suitable as a topcoat for photoresist in photolithography and immersion photolithography applications.

Abstract: An asymmetric siloxane is made by reacting a silicone having the formula MHDxM?H where MH is R1R2HSiO1/2, M?H is R4R5HSiO1/2 and x is an integer 0?x?10 under selective hydrosilylation conditions in the presence of a precious metal hydrosilylation catalyst, with a first olefinic compound and in a second step, a monohydridosiloxane produced in the first step is reacted under hydrosilylating conditions with another olefinic compound different from the first olefinic compound.

Abstract: An insulating liquid die-bonding agent for bonding a semiconductor-chip-mounting member to an active surface of a semiconductor chip, said agent comprising: (A) a mixture of (a-1) an organopolysiloxane resin having alkenyl groups and (a-2) a linear-chain organopolysiloxane having in one molecule at least two alkenyl groups; (B) an organopolysiloxane having in one molecule at least two silicon-bonded hydrogen atoms; (C) an organic silicon compound having in one molecule at least one silicon-bonded alkoxy groups; (D) insulating spherical silicone rubber particles having an average diameter of 0.1 to 50 ?m and having a type A durometer hardness according to JIS K 6253 equal to or below 80; and (E) a hydrosilylation-reaction catalyst, may not damage the active surface of the semiconductor chip, is well suited for screen printing, is resistant to the formation of voids on the interface between the semiconductor chip and the die-bonding agent, and does not lose its wire-bonding properties.

Abstract: A polycarbonate-polysiloxane copolymer comprising structural units of the formula: wherein each R1, R2, and R3 is independently the same or different monovalent C1-12 should this be C1-C13 like in the document? hydrocarbon group, G comprises a monovalent C6-1000 poly(oxyalkyl) group, each R4 and R5 taken together is independently the same or different divalent C3-30 hydrocarbon linking group wherein R4 is a C1-28 hydrocarbon and R5 is a C2-29 aliphatic group, a is 0 or greater, and b is one or greater; and structural units of the formula: wherein each R is independently the same or different C6-60 divalent hydrocarbon group, and at least 60% of the R groups comprise aromatic moieties.

Abstract: Provided is a transparent siloxane resin composition for optical applications, including: (1) a vinyl-oligosiloxane hybrid; (2) an organohydrosilicon compound having two or more silicon-bonded hydrogen atoms; and (3) a metal catalyst. A vinyl-oligosiloxane hybrid having an inorganic network structure and a high degree of condensation is prepared via a non-hydrolytic condensation reaction of an organosilanediol and an organoalkoxysilane having a vinyl group. When the organoalkoxysilane having a vinyl group is partly substituted with a metal alkoxide, a transparent siloxane resin for optical applications with high degree of condensation and refractive index can be prepared. The resulting transparent siloxane resin for optical applications exhibits excellent light transmittance, light resistance and heat resistance, has refractive index and hardness suitable for optical applications, and experiences little contraction during processing.

Abstract: A siloxane resin having the formula: (HSiO3/2)a(RSiO3/2)b(SiO4/2)c where R is Z, Z(CH2)n or ZO(CH2)n where Z is a phenyl or substituted phenyl group; n has a value of 1 to 6, a has value of 0.01 to 0.7, b has a value of 0.05 to 0.7, c has a value of 0.1 to 0.9 and a+b+c?1. The siloxane resins are useful in anti-reflective coating compositions.

Abstract: Linear or branched functionalized polycarbosilanes having an absorbance less than 3.0 ?m?1 at 193 nm and a relatively high refractive index are provided. The functionalized polycarbosilanes contain at least one pendant group that is acid labile or aqueous base soluble. Also disclosed are photoresists formulations containing the functionalized polycarbosilanes that are suitable for use in lithography, e.g., immersion lithography.

Abstract: The invention provides a process for preparing an overvoltage protection material comprising: (i) preparing a mixture comprising a polymer binder precursor and a conductive material; and (ii) heating the mixture to cause reaction of the polymer binder precursor and generate a polymer matrix having conductive material dispersed therein, wherein the polymer binder precursor is chosen such that substantially no solvent is generated during the reaction.

Abstract: An aromatic ring-containing polymer for a resist underlayer, the polymer including a unit represented by the following Chemical Formula 1: wherein, R1 and R2 are independently hydrogen, a C1 to C10 alkyl group, or an aromatic group, A is a functional group derived from an aromatic compound with a heteroatom or without a heteroatom, and n is an integer of one or more.

Abstract: A silicone composition comprising at least one organohydrogenpolysiloxane having an average of at least two silicon-bonded hydrogen atoms per molecule, a cross-linking agent having an average of at least two aliphatic carbon-carbon double bonds per molecule, and a hydrosilylation catalyst; a silicone adhesive comprising a cured product of at least one oganohydrogenpolysiloxane; and a coated substrate and a laminated substrate, each comprising the silicone adhesive.

Abstract: A silicone rubber coating composition comprising (A) a diorganopolysiloxane containing an average of at least two alkenyl groups, (B) silica powder having a specific surface area of at least 50 m2/g, (C) an organosilicon compound containing a ureido group, an isocyanuric acid ester modified with an organosilicon compound or a (partial) hydrolytic condensate thereof, and (D) a curing agent is applied and vulcanized to base fabric to form a coated fabric, from which airbags are prepared. The composition has a sufficient adhesion to withstand high temperature and abrupt elongation upon inflation of the airbag even after long-term storage under hot humid conditions.

Abstract: A hydrophilic organopolysiloxane composition of the hydrosilylation reaction cure type for use as dental impression material is characterized by comprising as essential components (A) a diorganopolysiloxane having at least 0.1 silicon-bonded alkenyl group in a molecule, (B) a liquid or solid organopolysiloxane having average compositional formula (1), comprising SiO2 units and R3SiO1/2 units (R is a monovalent hydrocarbon, alkoxy or hydroxyl group) and having a viscosity of at least 10 mPa-s at 23° C., (C) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule, (D) a hydrosilylation catalyst, and (E) a polyether having average compositional formula (2).

Abstract: A method of controlling oil-absorbing properties of a silicone rubber powder characterized by keeping a silicone rubber powder in hot storage at a temperature in the range of 40° C. to 150° C. or in cold storage at a temperature in the range of 0° C. to 10° C.

Abstract: An organohydrogenpolysiloxane comprising at least two structural units of —(HR1SiO)a— wherein R1 is a monovalent hydrocarbon group, and a is an integer of 2-50, which are connected together via a SiH-free structural unit, is a novel crosslinking agent. A silicone composition comprising an alkenyl-containing organopolysiloxane, the organohydrogenpolysiloxane, and a catalyst is curable through addition reaction, adherent to plastic substrates, and useful for coating purposes.

Abstract: A curable composition comprises a reactive silicon group-containing polyoxyalkylene polymer which is obtained by reacting a polyoxyalkylene polymer (A) having a molecular weight distribution of 1.6 or less, a number average molecular weight of 15,000 to 50,000, and 0.8 or more reactive groups, on average, per molecule thereof with an organic compound (B) having in the molecule thereof a reactive silicon group and a functional group capable of reacting with the reactive groups of the polymer (A) in a proportion of 0.8 to 1.5 molecules of the organic compound (B), on average, per molecule of the component (A), a filler (C) and a curing catalyst (D). The composition contains no plasticizer or a small amount of plasticizer.

Abstract: A coating composition comprises a fluoroelastomer composition and a diluent solvent consisting of a perfluoroalkyl-substituted aromatic compound and a perfluoro organic compound, the fluoroelastomer composition comprising (A) a linear perfluoropolyether compound, (B) a fluorinated organohydrogensiloxane, (C) a platinum catalyst, and (D) an organopolysiloxane containing an SiH group and an epoxy or trialkoxysilyl group. The composition cures into a fluoroelastomer having excellent characteristics and achieves a firm adhesion to a broad range of substrates by brief heating at relatively low temperatures.

Abstract: This invention pertains to silsesquioxane resins useful in antireflective coatings wherein the silsesquioxane resin is comprised of the units (Ph(CH2)rSiO(3?x)/2(OR?)x)m (HSiO(3?x)/2(OR?)x)n (MeSiO(3?x)/2(OR?)x)o (RSiO(3?x)/2(OR?)x)p (R1SiO(3?x)/2(OR?)x)q where Ph is a phenyl group, Me is a methyl group; R? is hydrogen atom or a hydrocarbon group having from 1 to 4 carbon atoms; R is selected from a hydroxyl producing group; and R1 is selected from substituted phenyl groups, ester groups, polyether groups; mercapto groups, and reactive or curable organic functional groups; and r has a value of 0, 1, 2, 3, or 4; x has a value of 0, 1 or 2; wherein in the resin m has a value of 0 to 0.95; n has a value of 0.05 to 0.95; o has a value of 0.05 to 0.95; p has a value of 0.05 to 0.5; q has a value of 0 to 0.5; and m+n+o+p+q?1.

Abstract: There is provided herein, in one specific embodiment, silicone composition(s) comprising unique combination(s) of silicone polymer and alkyltrisiloxane(s) which can produce silicone composition(s) with lower solids content than silicone compositions that use other than alkyltrisiloxane(s); while still maintaining a desirable viscosity.

Abstract: A curable organopolysiloxane resin composition having a viscosity at 25° C. in the range of 0.001 to 5,000 Pa·s, a total acid number as specified by JIS K 2501 (1992) in the range of 0.0001 to 0.2 mg/g, and light transmittance in a cured state equal to or greater than 80%; an optical part comprised of a cured body of the aforementioned composition. The curable organopolysiloxane resin composition of the invention is characterized by good transparency, low decrease in transmittance when exposed to high temperatures, and excellent adhesion when required.

Abstract: Cardanol based dimers are provided. The cardanol dimers are formed by hydrosylylation with silanes. Cardanol based dimers may be further reacted to form epoxy curing agents and epoxies which can be used as anti-fouling coatings on ship hulls and marine structures. The cardanol dimers may also be used to produce friction particles or phenolic resins. Methods of synthesizing the cardanol based dimers, the epoxy curing agents and the epoxies are also provided.

Abstract: An addition curable adhesive silicone composition containing a phosphor dispersed uniformly therein is provided. The dispersive state of the phosphor remains stable over time. The composition, in an uncured state at room temperature, is either a solid or a semisolid, and is therefore easy to handle, and is suited to an adhesive silicone composition sheet which is able to be formed easily on an LED chip using a conventional assembly apparatus.

Abstract: The present invention relates to a perfluoropolyether-modified polysiloxane represented by general formula (1): wherein Rf is a linear or branched perfluoroalkyl group having 1 to 10 carbon atoms; X is a fluorine atom or a trifluoromethyl group; Q is a divalent organic group having 1 to 12 carbon atoms; R1, R2, and R3 are, independently of each other, an alkyl group having 1 to 10 carbon atoms or an aryl group; a, b, c, and d are, independently of each other, an integer of from 0 to 200, provided that a total of a, b, c and d is 1 or larger; e is an integer of 0 or 1; and z is an integer of from 5 to 100; a method for preparing the same; and a defoaming agent comprising the same.

Abstract: Provided herein, according to some embodiments of the invention, are organosilane polymers prepared by reacting organosilane compounds including (a) at least one compound of Formula I Si(OR1)(OR2)(OR3)R4??(I) wherein R1, R2 and R3 may each independently be an alkyl group, and R4 may be —(CH2)nR5, wherein R5 may be an aryl or a substituted aryl, and n may be 0 or a positive integer; and (b) at least one compound of Formula II Si(OR6)(OR7)(OR8)R9??(II) wherein R6, R7 and R8 may each independently an alkyl group or an aryl group; and R9 may be an alkyl group. Also provided are hardmask compositions including an organosilane compound according to an embodiment of the invention, or a hydrolysis product thereof. Methods of producing semiconductor devices using a hardmask compostion according to an embodiment of the invention, and semiconductor devices produced therefrom, are also provided.

Abstract: The invention relates to emulsifier systems containing ester-modified, polyether-free organopolysiloxanes, to their use, in particular the production of cosmetic, dermatological or pharmaceutical formulations and also of care and cleaning compositions, and also the products themselves produced with the help of the emulsifier systems.

Abstract: Curable fluoropolyether compositions comprising (a) a polyfluorodialkenyl compound, (b) a fluorinated organohydrogenpolysiloxane, (c) a platinum catalyst, (d) hydrophobic silica powder, (e) a tackifier in the form of a specific silicon compound, and (f) an organosiloxane having a SiH group, an epoxy and/or trialkoxysilyl group, and a perfluoroalkyl or perfluoropolyether group cure to thermoplastic resins to form a durable tight bond at a low temperature within a short time and are readily releasable from metal molds.

Abstract: A silicone resin composition is provided, which includes an alkenyl group-containing polysiloxane represented by the following average composition formula (PSA(1)), a hydro group-containing polysiloxane represented by the following average composition formula (PSA(2)), two kinds of polysiloxane, both having opposite ends sealed with a vinyl group, which are represented by the following formulas (PSC(1) and PSC(4)), and a hydrosilylating catalyst:

Abstract: Provided are a silicone resin that yields a cured product excellent in flexibility, toughness, and heat resistance and high in transparency, a process for producing the said silicone resin, and a curable resin composition comprising the said silicone resin. The silicone resin is obtained by reacting an organopolysiloxane containing SiH groups represented by general formula (3) with an organopolysiloxane containing hydroxyl groups at both ends represented by general formula (5) and an alcohol containing radically reactive groups represented by general formula (6) in the presence of a hydroxylamine compound represented by general formula (4) as a catalyst and this silicone resin is used in formulating a curable resin composition.

Abstract: A method of manufacturing an analytical sample by a secondary ion mass spectrometry method is provided, which comprises a step of forming a separation layer over a substrate, a step of forming one of a thin film and a thin-film stack body to be analyzed over the separation layer, a step of forming an opening portion in one of the thin film and the thin-film stack body, a step of attaching a supporting body to one of a surface of the thin film and a surface of a top layer of the thin-film stack body, and a step of separating one of the thin film and the thin-film stack body from the substrate.

Abstract: A poly(arylene ether) composition includes a hydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene, a flame retardant, and a poly(arylene ether)-polysiloxane block copolymer reaction product that itself includes a poly(arylene ether)-polysiloxane block copolymer. The composition is useful for forming extruded articles, including insulation for wire and cable. The poly(arylene ether)-polysiloxane block copolymer contributes improved flame retardancy and, in many cases, improved physical properties to the composition.

Abstract: The present invention relates to a series of crosslinked silicone polymers that by virtue of the nature of the crosslinker, have unique film forming and skin feel properties. They are made by the reaction of vinyl silicones and star silanic hydrogen compounds.

Abstract: Self-adhesive addition-crosslinking silicone compositions contain (A) at least one diorganopolysiloxane, (B) at least one SiH-containing crosslinker containing a defined fraction of radicals, with the proviso that the viscosity of the organohydropolysiloxane (B) as determined at 25° C. is 5 mPa·s to 5 Pa·s, (C) at least one organohydrooligosiloxane, and (D) at least one hydrosilylation catalyst.

Abstract: An extremely durable, stable and fast-curing elastomeric composition suitable for coating all types of architectural and decorative glass is disclosed.

Abstract: A siloxane resin having the formula: (HSiO3/2)a(RSiO3/2)b(SiO4/2)c where R is Z, Z(CH2)n or ZO(CH2)n where Z is a phenyl or substituted phenyl group; n has a value of 1 to 6, a has value of 0.01 to 0.7, b has a value of 0.05 to 0.7, c has a value of 0.1 to 0.9 and a+b+c?1. The siloxane resins are useful in anti-reflective coating compositions.

Abstract: A perfluoropolyether rubber composition is useful for forming a polymer electrolyte membrane, comprising (A) an alkenyl-containing perfluoropolyether, (B) a silicon-oxygen crosslinked structure having ionic conduction, and (C) a peroxide crosslinker. The silicon-oxygen crosslinked structure is obtained by simultaneously effecting oxidation and hydrolysis on an organoxysilane having an epoxy group and an organoxysilane having a mercapto group for thereby converting the mercapto group into a sulfonic group, and neutralizing the resulting sulfonic group-containing siloxane with a nitrogen-containing compound.

Abstract: The invention relates to novel polyester-polysiloxane block copolymers, to a process for their preparation and to the use of these polymers as a base oil or as an additive in lubricants, especially silicone oils.

Abstract: Silsesquioxane resins useful in forming the antireflective coating having the formula (PhSiO(3-x)/2(OH)x)mHSiO(3-x)/2(OH)x)n(MeSiO(3-x)/2(OH)x)p(RSiO(3-x)/2(OH)x)q where Ph is a phenyl group, Me is a methyl group, R is selected from ester groups and polyether groups, x has a value of 0, 1 or 2; m has a value of 0.05 to 0.95, n has a value of 0.05 to 0.95, p has a value of 0.05 to 0.95, q has a value of 0.01 to 0.30 and m+n+p+q?1.

Abstract: An asymmetric siloxane is made by reacting a silicone having the formula MHDxM?H where MH is R1R2HSiO1/2, M?H is R4R5HSiO1/2 and x is an integer 0?x?10 under selective hydrosilylation conditions in the presence of a precious metal hydrosilylation catalyst, with a first olefinic compound and in a second step, a monohydridosiloxane produced in the first step is reacted under hydrosilylating conditions with another olefinic compound different from the first olefinic compound.