Abstract: The present invention relates to a new process for manufacturing a silicon carbide (SiC) coated body by depositing SiC in a chemical vapor deposition method using dimethyldichlorosilane (DMS) as the silane source on a graphite substrate. A further aspect of the present invention relates to the new silicon carbide coated body, which can be obtained by the new process of the present invention, and to the use thereof for manufacturing articles for high temperature applications, susceptors and reactors, semiconductor materials, and wafer.

Abstract: A liquid aryl group-containing polyorganosiloxane comprising an arylsiloxy unit represented by RSiO3/2 (wherein R is an aryl group), wherein: the arylsiloxy unit constitutes from 20 to 50 mol % of all the siloxy units constituting the polymer, and an average number of moles of aryl groups per 1 mole of Si atoms in the molecule is within a range of 1.20 to 1.65. A composition with an oil agent of the same, wherein the overall refractive index of the composition is not less than 1.45, and an overall viscosity at 25° C. of the composition is in a range from 100 to 100,000 mPa·s.

Abstract: The present invention relates to a method for preparing di-organo-dialkoxysilanes, in particular di-organo-dialkoxysilanes wherein one or both of the organic substituents are bulky. The method comprises reacting a tetraalkoxysilane compound with a first Grignard reagent to form a mono-organo-tri-alkoxysilane compound, which is then reacted with a chlorinating agent to form a chlorinated mono-organo-di-alkoxysilane which is then reacted with a second Grignard reagent to form the di-organo-di-alkoxysilane compound.

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 relates to a polysiloxane compound having a structure represented by formula 1: wherein each of F1, F2, F3 and F4 is individually selected from one of a first group, a second group, a third group and a fourth group, the first group is selected from a C2˜C10 hydrocarbon group having amino group(s), a C2˜C10 hydrocarbon group having epoxy group(s), a C2˜C10 hydrocarbon group having carbonyl group(s) or a C2˜C10 hydrocarbon group having alkoxy group(s), the second group is a C2˜C10 hydrocarbon group having amino group(s), the third group is selected from a C2˜C10 hydrocarbon group having epoxy group(s), a C2˜C10 hydrocarbon group having carbonyl group(s), a C2˜C10 hydrocarbon group having SiCl group(s) or a C2˜C10 hydrocarbon group having alkoxy group(s), the fourth group is selected from a C2˜C10 hydrocarbon group having aryl group(s) or a C2˜C10 hydrocarbon group having alkoxy group(s).

Abstract: The invention relates to a method for producing dimeric and/or trimeric silicon compounds, in particular silicon halogen compounds. The claimed method is also suitable for producing corresponding germanium compounds. The invention also relates to a device for carrying out said method to the use of the produced silicon compounds.

Abstract: A method of forming an MT-propyl siloxane resin includes the steps of hydrolyzing propyl trichlorosilane in an excess of water to provide a T-propyl siloxane resin and capping the T-propyl siloxane resin formed from the hydrolysis of the propyl trichlorosilane with a silicon-containing M-group capping agent to form the MT-propyl siloxane resin. The MT-propyl siloxane resin is useful in a variety of personal care applications, and in particular, as an additive to personal care compositions.

Abstract: The present invention relates to a preparation method for a linear or cyclic trisilaalkane which is a substance useful in the preparation of polycarbosilane and silicon carbide precursors. Linear or cyclic trisilaalkane and organic trichlorosilane derivatives can be synthesized simultaneously and in high yield by reacting bis(chlorosily)methane having a Si—H bond, either alone or together with an organic chloride, using a quaternary organic phosphonium salt compound as a catalyst. Further, since the catalyst can be recovered after use, the present invention is very economical and is thus effective for mass-producing precursors for organic/inorganic hybrid substances.

Abstract: The present disclosure provides methods for treating a surface for single-molecule imaging.

Abstract: A hydrophobic and lipophobic coating material comprising nanoparticles with a molecule having the formula (I): wherein R1 is selected from a group consisting of halogens, hydrogen, alkyl groups, alkoxy groups, hydroxyl group, alkenyl groups, alkynyl groups, acyl groups, aryl groups, carboxyl groups, alkoxycarbonyl groups, and aryloxycarboxyl groups, and wherein R2 is a functional group containing fluorine. The coating material may be coated on an outer cover or a conductive layer of a touchscreen. The coating material has superior hydrophobicity and lipophobicity, facilitating a touchscreen easy to clean and exempting the touchscreen from fingerprints and oily stains. The coating material also has superior antiglare effect.

Abstract: A liquid crystal molecule is disclosed, having a structure represented by the following general formula (1): wherein X1 is a group selected among groups represented by the following formula (2): X2 is represented by the following formula (3): R1 represents a linear or branched hydrocarbon group or an alkoxy group each having from 4 to 16 carbon atoms; R2 represents an optionally branched organosiloxane or organosilane having from 1 to 6 silicon atoms; other variables in formulae are defined therein.

Abstract: The invention relates to a method for processing mixtures which contain HCl, H2O and siloxanes in the presence of packings comprising fluorinated vinyl 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: Chlorosilanes are hydrolyzed to a hydrolysate in a looped system containing a hydrolysis reactor, an HCl purifier, a wash means, and a separator. The steps of the method comprise: (i) feeding chlorosilanes from an external source to the hydrolysis reactor, (ii) feeding water from an external source to the wash means, (iii) feeding a high concentration aqueous HCl of at least 10 percent by weight HCl from an external source to the hydrolysis reactor between the wash means and the hydrolysis reactor, (iv) removing anhydrous hydrogen chloride from the HCl purifier, (v) removing hydrolysate from the wash means, and (vi) removing a low concentration aqueous hydrogen chloride of 0.1 to less than 10 percent by weight HCl from the looped system.

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 compound of the general formula R1R2MR4R5 is disclosed wherein R1 and R2 are independently an aryl, alkyl, alkenyl, epoxy or alkynyl group, wherein at least one of R1 and R2 is fully or partially fluorinated, wherein M is selected from group 14 of the periodic table, wherein R4 and R5 are independently an alkoxy group, OR3, or a halogen group, X, except where M is Si, R4 and R5 are both ethoxy groups or both chlorine groups, and R1 and R2 are perfluorinated groups. This compound formed can be further reacted to attach an additional organic R group, and/or hydrolyzed, alone or with one or more similar compounds, to form a material having a molecular weight of from 500 to 10,000, which material can be deposited on various substrates as a coating or deposited and patterned for a waveguide or other optical device components. Methods for making compounds of the general formula R1MR4R5R6 are also disclosed.

Abstract: Provided are polyorganosilsesquioxane and process for preparing the same. The polyorganosilsesquioxane is obtained by various methods including polymerization of 1,3-diorganosiloxane, a precursor that is prepared by using silane compounds 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: Method is provided for selectively opening rings of polyhedral oligomeric silsesquioxane (POSS) compounds to from functionalized derivatives thereof or new POSS species. Per the inventive method, the POSS compound is reacted with an acid to selectively cleave bonds in the POSS rings to add functionalities thereto for grafting, polymerization or catalysis, to thus form new familes of POSS derived compounds. Also provided are the new compounds so formed. Method is also provided for expanding rings of POSS compounds. Per the inventive method, a POSS compound is reacted with silane reagents to obtain an expanded POSS framework with added Si ring substituends to form new families of POSS compounds. Also provided are the new compounds so formed.

Abstract: The invention relates to a method of producing silane or hydrochlorosilanes by disproportionation of a higher chlorinated hydrochlorosilane or a mixture of said hydrochlorosilanes in the presence of a catalyst. Before the catalyst is used, it is a) washed with hyper-pure water in one or several steps; b) transferred in the water-moist state to the reactor in which the disproportionation is to proceed; c) treated in the reactor with boiling methanol or rinsed with anhydrous methanol; and d) the methanol is removed from the catalyst by evacuation and/or stripping with inert gas. The invention further relates to a method for treating disproportionation catalysts.

Abstract: Method is provided for controlling the stereo chemistry of functionalities or X groups to exo or endo positions on a polyhedral oligomeric silsesquioxane (POSS) compound by adding certain reagents to said X groups to change one or more positions thereof to endo or exo. Also provided are the POSS species formed by the above inventive method. Method is also provided for inserting a ring substituent into a POSS compound. Also provided are the POSS species formed by such inventive method.

Abstract: This invention relates to a series of fluoroalkylsilane compounds of formula I. These compounds are silylation reagents which enhance the solubility of the silylated products in fluorocarbon solvents for preferred use in fluorous phase synthesis. Use of these compounds protects fragile hydrogen groups and also provides for the straightforward separation of the ultimate reaction products though fluorous phase extraction. This invention also relates to a two-step process for making compounds of formula I. The process comprises reacting an alkyldialkoxysilane with a perfluoroalkyl-substituted silane to produce a perfluoroalkyl-substituted dialkylsiloxyalkylsilane intermediate; and reacting the intermediate with halogen.

Abstract: The present invention pertains to a method for manufacturing a hydrogen-silsesquioxane resin in which a solution of HSiCl3 in a halogenated hydrocarbon solvent which can dissolve the organic sulfonic acid described below and which does not react with sulfuric acid is added to a two-phase system comprising [a] an aqueous phase which contains sulfuric acid and an organic sulfonic acid which is not sulfonated by sulfuric acid and which is soluble in both water and the organic phase described below, and [b] an organic phase which contains the halogenated hydrocarbon solvent, and the resulting mixture is agitated. In this method, the ratio of the sulfuric acid relative to the combined weight of the water (including water of hydration in cases where the above sulfonic acid contains such water of hydration) and sulfuric acid is 80 to 96 wt %, and is present in the organic phase at the rate of 0.008 moles/L or greater.

Abstract: This invention relates to a macromonomer and a method for its preparation. The macromonomer has one or more silicon-bonded hydrogen atoms at one molecular chain terminal, and one or more aliphatically unsaturated silicon-bonded organic groups at the other molecular chain terminal. This invention further relates to a method of forming a hyperbranched polymer by polymerizing the macromonomer with a group VIII metal catalyst. The hyperbranched polymers can be used as surfactants, gelling agents, drug delivery systems, and polymeric absorbents.

Abstract: 1,3-dihalo-1,1,3,3-tetra(organyl)disiloxanes of the general formula XR2Si—O—SiR2X  (1) are prepared by reacting hydrogen halide with the corresponding 1,3-dihydro-1,1,3,3-tetra(organyl)disiloxanes of the general formula HR2Si—O—SiR2H  (2), in which R is an alkyl or halogen substituted alkyl group and X is halogen, in the presence of a catalyst selected from transition metals of the 8th subgroup of the periodic table of the elements, or compounds or complexes of these transition metals.

Abstract: This invention relates to a macromonomer and a method for its preparation. The macromonomer has silicon-bonded hydrogen atoms at one molecular chain terminal, and aliphatically unsaturated silicon-bonded organic groups at the other molecular chain terminal. This invention further related to a method of forming a hyperbranched polymer by polymerizing the macromonomer with a group VIII metal catalyst. The hyperbranched polymers can be used as surfactants, gelling agents, drug delivery systems, and polymeric absorbents.

Abstract: A silacyclobutane compound having the formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently chloro, triorganosiloxy, organooxy, triorganosilyl, or a monovalent hydrocarbon group; R.sup.3 is a monovalent hydrocarbon group free of conjugated aliphatic unsaturation, triorganosilyl, or hydrogen; and R.sup.4 is a monovalent saturated hydrocarbon group; provided that when R.sup.3 is hydrogen, neither R.sup.1 nor R.sup.2 is chloro or organooxy. Methods of preparing the silacyclobutane compounds, silane polymers containing at least one silacyclobutane unit, and siloxane polymers containing at least one silacyclobutane unit.

Abstract: The present invention describes a process wherein dimethyldichlorosilane is reacted, in a first step, with water present in hydrochloric acid to give a crude hydrolysate comprising cyclic and linear, chlorine-containing polydimethylsiloxanes and gaseous hydrogen chloride and, in a second step, the crude hydrolysate is treated with steam to reduce the chlorine content and form hydrochloric acid, with the hydrochloric acid formed in the second step being used in the first step.

Abstract: Disclosed is a method of producing dimethylpolysiloxanes through hydrolysis of dimethyldichlorosilane wherein a water solution containing a water-soluble oxygen-containing organic compound is introduced into dimethyldichlorosilane. Therein, linear dimethylpolysiloxanes alone having both ends blocked with chlorine atoms can be selectively produced by properly controlling the water content in the hydrolysis system and further by rendering the hydrolysis system acidic, and cyclic dimethylpolysiloxanes alone can also be selectively produced by properly controlling the water content in the hydrolysis system and optionally rendering the hydrolysis system acidic.

Abstract: The invention provides silicon substituted fullerene compounds. The compounds can form polymers or wrapped fullerenes. The compounds may be made by reacting an organo-silicon compound with a fullerene in the presence of a catalyst by a hydrosilylation reaction.

Abstract: The present invention concerns novel reactive polysiloxanes and a method for their manufacture. More specifically, the present invention concerns polysiloxanes of mainly SiO.sub.4/2 polysiloxane units which have highly reactive halogen atoms bonded to silicon and a method for their manufacture.

Abstract: The present invention is novel chlorine end-terminated organosiloxanes and a hydrosilylation process for their preparation. The process comprises contacting a chlorine end-terminated (organohydrogen)siloxane and an .alpha.-olefin in the presence of a platinum catalyst, at a temperature of 50.degree. C. to 200.degree. C. The products of this process are chlorine end-terminated organosiloxanes.

Abstract: Alpha-fluorinated olefins are hydrosilated using selected cobalt compounds as catalysts. The products are useful in coatings, and as chemical intermediates, elastomers, and caulks.

Abstract: A method for metallizing a polymeric substrate is disclosed. The method includes contacting a surface of an etched polymeric substrate with a silane coupling agent and depositing a metallic layer over the surface. The silane coupling agent forms a chemical linkage between the substrate and the metallic layer. A coupling agent composition and a metallized polymeric substrate are also described.

Abstract: The instant invention is a one-step process for producing polydiorganosiloxanes (siloxanes). In the described process, a mixture comprising diorganodichlorosilane and a source of triorganosilyl groups is contacted with excess water essentially saturated with hydrogen chloride. Product siloxanes are isolated as well as saturated aqueous hydrogen chloride and anhydrous hydrogen chloride. The amount of triorganosilyl groups present in the mixture is controlled to set the degree of polymerization of product siloxanes. The isolated saturated aqueous hydrogen chloride is recycled to the process. Excess chloride generated in the process is collected as anhydrous hydrogen chloride.

Abstract: The instant invention is a catalyzed process for the redistribution of linear, chloride or hydroxy end-terminated polyorganosiloxanes or cyclic polyorganosiloxanes. Effective catalysts for the described process are alumina, silica-alumina, activated carbon, zeolite, and acid clay. The catalyzed redistribution process can be incorporated as an element of a three-stage process. The three-stage process allows control of the yield of cyclic polyorganosiloxanes.

Abstract: A process for producing a polysiloxane oil with aryl groups and oxygen atoms as co-substituents on the silicon atoms. Silicon monoxide gas is reacted under a vacumm with iodine and an aromatic compound such as toluene in solution at a low temperature in the region of -75.degree. C. to -95.degree. C.

Abstract: Organosiloxanes (1) of the general formulaR.sup.1.sub.4-n Si(OSiR.sub.3).sub.n,in which R is the same or different and represents a hydrogen atom or a monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical or a substituted monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical, R.sup.1 represents R or a chlorine atom, and n is 3 or 4, are prepared by reacting organodisiloxanes (2) of the general formula(R.sub.3 Si).sub.2 O,with chlorosilanes (3) of the general formulaR.sub.4-n SiCl.sub.n,in which R and n are the same as above, in the presence of phosphonitrile chlorides (4) and cocatalysts (5), in which the cocatalysts (5) are used concomitantly with the phosphonitrile chlorides (4) and are selected from the group consisting of amides of the general formulaX--C(O)--R.sup.2,in which R.sup.

Abstract: The present invention provides a relatively simple synthesis procedure for the formation of silane hydrolyzate compositions of the formula ##EQU1## where R is hydrogen or a methyl group, n is an integer greater than about 8, and x is a number between 0 and 2. The hydrolyzate compositions are metastable in solvent solution but become insoluble after coating on a substrate. The resins are useful as planarizing coatings for substrates such as electronic devices and can be ceramified by subjecting them to an oxidizing atmosphere at a temperature of between about 100.degree. to 1000.degree. C. to form ceramic or ceramic-like coatings on such substrates.

Abstract: A method is provided for silylating aromatic acylhalide by effecting reaction between an aromatic acylhalide and halogenated polysilane in the presence of an effective amount of a supported transition metal catalyst, such as a transition metal catalyst supported by an organic or inorganic substrate.

Abstract: A method is provided for silylating organic substrates, utilizing a halogenated polysilane, such as 1,1,2,2-tetrachloro dimethyldisilane and an aromatic acyl halide, for example, trimellitic anhydride acid chloride in the presence of a transition metal catalyst.

Abstract: A process is disclosed for the direct synthesis of cyclic and oligomeric organosiloxanes, such as dimethylsiloxanes, comprising reacting a hydrocarbon ether and a hydrocarbon halide with a fluidized or agitated bed of activated silicon particles with a maximum contact time of five minutes, and continuously withdrawing products from that reaction.

Abstract: The invention discloses a novel cyclic organopolysiloxane compound having one or more of 3,3,3-trifluoropropyl groups and one or more of alkenyloxy groups, e.g. isopropenyloxy group of the formula --O--C(CH.sub.3).dbd.CH.sub.2, each directly bonded to the silicon atom in a molecule. This novel organopolysiloxane compound is useful as a crosslinking agent for a hydroxy-terminated diorganopolysiloxane and a formulation of a room temperature curable organopolysiloxane composition capable of giving a rubbery elastomer by curing is proposed comprising, each in a limited proportion, (a) a hydroxy-terminated diorganopolysiloxane, (b) the above disclosed novel cyclic organopolysiloxane having 2 or 3 alkenyloxy groups, (c) a second cyclic organopolysiloxane having 2 or 3 alkenyloxy groups each directly bonded to the silicon atom in a molecule and (d) a guanidino-containing organosilicon compound, e.g. 3-(tetramethylguanidino)propyl trimethyl silane, as a curing accelerator.

Abstract: This invention relates to a process for the preparation of polysiloxanes by reacting halosilanes in the presence of metal oxides and sulfolane. Preferred metal oxides include antimony (III) oxide, antimony (V) oxide, cadmium oxide, calcium oxide, copper (II) oxide, indium oxide, iron (II) oxide, iron (III) oxide, magnesium oxide, manganese (II) oxide, mercury (II) oxide, nickel (II) oxide, thallium (III) oxide, tin (II) oxide, and zinc oxide. Improved yields and rates of reaction can be observed with the process of this invention.

Abstract: [2-(p-t-Butylphenyl)ethyl]silanes are provided having the general formula:Si(B).sub.x (R).sub.y (A).sub.zwherein B is a (p-t-butylphenyl)ethyl moiety, R is an alkyl or aryl moiety and A is a hydrolyzeable moiety; x equals 1 or 2, y equals 0, 1 or 2 and z equals 1, 2 or 3 such that x plus y plus z equals 4. The bulky substituted silanes are produced by the hydrosilylation of p-t-butylstyrene.[2-(p-t-Butylphenyl)ethyl] substituted disiloxanes are also provided, having the general formula:(B).sub.x (R).sub.y (A).sub.z Si--O--Si(A).sub.z (R).sub.y (B).sub.xwherein B, R, A, x, y and z are as defined above except that z equals 0,1 or 2 and x plus y plus z equals 3. The bulky substituted disiloxanes are produced by the hydrolysis of above-described bulky substituted silanes.

Abstract: A process is described by which numerous waste or by-product chlorosilane streams can be treated to obtain a granular gel that is easily handleable in further processing steps, shipment, or disposal operations. By hydrolyzing a combined stream with an average SiCl functionality greater than or equal to 2.8 in an aqueous medium at elevated temperature a granular gel is obtained in all cases. The combined stream can be formed by blending several different streams to obtain the desired average SiCl functionality. If the aqueous medium is concentrated hydrogen chloride, the hydrogen chloride generated in the hydrolysis step can be recovered.

Abstract: A method is provided for hydrolyzing organochlorosilanes using concentrated or saturated aqueous hydrogen chloride solution as the source of water. There is employed a ratio of about 10 to about 30 moles of water per mole of organochlorosilane. In addition to recovering gaseous hydrogen chloride without distillation of aqueous hydrogen chloride solution, the organopolysiloxane hydrolyzate in the form of linear and cyclic siloxanes has reduced total chloride content in the form of dissolved hydrogen chloride and chlorine-terminated linear siloxanes.

Abstract: A method for preparing cyclotetrasiloxane, aliphatic chlorides and/or acyl chlorides from a cyclotrisiloxane, a chlorosilane and an acyloxy compound is disclosed. The chlorosilane and the acyloxy compound may be present as substantially equimolar amounts of separate compounds or they may be present in the same molecule in equimolar amounts. The reactants are merely heated sufficiently, with or without a soluble halide salt catalyst, to form the products. Advantageously this method can provide cyclotetrasiloxanes having water-sensitive radicals such as silicon-bonded chlorine atoms and/or silicon-bonded acyl chloride radicals. This method also provides a method for preparing cyclotetrasiloxanes having either one type of siloxane unit (non-mixed cyclotetrasiloxanes) or more than one type of siloxane unit (mixed cyclotetrasiloxanes).

Abstract: A method for preparing cyclotetrasiloxane, aliphatic chlorides and/or acyl chlorides from a chlorosilane and an acyloxy compound is disclosed. The chlorosilane and the acyloxy compound may be present as substantially equimolar amounts of separate compounds or they may be present in the same molecule in equimolar amounts. The reactants are merely heated sufficiently, with or without a soluble halide salt catalyst, to form the products. Advantageously this method can provide cyclotetrasiloxanes having water-sensitive radicals such as silicon-bonded chlorine atoms and/or silicon-bonded acyl chloride radicals.

Abstract: A method of neutralizing a halogen silicone compound comprising adding to the halogen silicone compound an orthoformate and an alcohol so as to form an alkyl chloride and a formate which can then be distilled off.

Abstract: Siloxanes having units containing the grouping (XOQO) Si.tbd. in which X represents hydrogen or a chemical bond linking the adjacent oxygen atom to the silicon atom of a silyl or siloxy group and Q represents ##STR1## or--CH(C.sub.3 H.sub.7)CH(C.sub.2 H.sub.5)CH.sub.2 --They are prepared by reacting a siloxane with 2-butyl-2-ethylpropane-1,3-diol or 2-ethylhexane-1,3-diol and are useful for imparting insect repellent properties to surfaces.