A composition, comprising: trisilylamine and less than 5 ppmw of halogen. A method of making a silylamine comprising combining ammonia and a compound comprising aminosilane functionality, where the compound comprising aminosilane functionality is according to formula (I) R.sup.1 N(R.sup.2)a(SiH.sub.3).sub.2a (I), where R.sup.1 is an organic polymer, a C-.sub.1-20 hydrocarbyl group or SiR.sup.3.sub.3.sup.1, where R.sup.3 is C.sub.1-6 hydrocarbyl, R.sup.2 is a C-.sub.1-20 hydrocarbyl group, H, or -SiR.sup.3.sub.3.sup.1 , where R.sup.3 is as defined above, subscript a is 0 or 1, provided that R.sup.1 and R.sup.2 may be the same or different except if R.sup.1 is phenyl, R.sup.2 is not phenyl, under sufficient conditions to cause a reaction to form a silylamine and a byproduct.

The present invention relates to a process for preparing isocyanate containing alkoxysilane groups, in which, in the sequence of steps A) to D), A) alkoxysilanoalkylamine is reacted with urea in the presence of an alcohol, optionally in the presence of at least one catalyst, to give alkoxysilanoalkylurethane, B) simultaneously or successively, if used, the catalyst is removed and/or deactivated, and low boilers, medium boilers and/or high boilers are removed, C) purified alkoxysilanoalkylurethane is thermally cleaved to release isocyanate containing alkoxysilane groups and by-product, leaving bottoms material, and D) isocyanate containing alkoxysilane groups and by-product are separated from one another and from bottoms material and collected, in which, in step C), i) the bottoms material is wholly or partly discharged from the cleavage apparatus, ii) subjected to thermal treatment and/or purification and/or an aftertreatment in the presence of alcohol and iii) the material removed, after thermal treatment and/or purification and/or aftertreatment in step B) or C), is fed in again.

The present invention relates to a process for preparing isocyanate containing alkoxysilane groups, in which, in the sequence of steps A) to D), A) alkoxysilanoalkylamine is reacted with urea in the presence of an alcohol, optionally in the presence of at least one catalyst, to give alkoxysilanoalkylurethane, B) simultaneously or successively, if used, the catalyst is removed and/or deactivated, and low boilers, medium boilers and/or high boilers are removed, C) purified alkoxysilanoalkylurethane is thermally cleaved to release isocyanate containing alkoxysilane groups and by-product, leaving bottoms material, and D) isocyanate containing alkoxysilane groups and by-product are separated from one another and from bottoms material and collected, in which, in step C), i) the bottoms material is wholly or partly discharged from the cleavage apparatus, ii) subjected to thermal treatment and/or purification and/or an aftertreatment in the presence of alcohol and iii) the material removed, after thermal treatment and/or purification and/or aftertreatment in step B) or C), is fed in again.

The invention relates to a process for preparing isocyanate containing alkoxysilane groups, in which, in the sequence of steps A) to D), A) alkoxysilano(cyclo)alkylamine is reacted with dialkyl carbonate in the presence of a basic catalyst to give alkoxysilano(cyclo)alkylurethane, B) simultaneously or successively, the catalyst is deactivated, and low boilers, solids, salt burdens and/or high boilers are removed, C) alkoxysilano(cyclo)alkylurethane obtained after B) is thermally cleaved to release isocyanate containing alkoxysilane groups and by-product, leaving bottoms material, and D) isocyanate containing alkoxysilane groups and by-product are separated from one another and from bottoms material and collected,
wherein the process regime at least of steps C) to D) is continuous.

The invention relates to a process for preparing isocyanate containing alkoxysilane groups, in which, in the sequence of steps A) to D), A) alkoxysilano(cyclo)alkylamine is reacted with dialkyl carbonate in the presence of a basic catalyst to give alkoxysilano(cyclo)alkylurethane, B) simultaneously or successively, the catalyst is deactivated, and low boilers, solids, salt burdens and/or high boilers are removed, C) alkoxysilano(cyclo)alkylurethane obtained after B) is thermally cleaved to release isocyanate containing alkoxysilane groups and by-product, leaving bottoms material, and D) isocyanate containing alkoxysilane groups and by-product are separated from one another and from bottoms material and collected,
wherein the process regime at least of steps C) to D) is continuous.

Organosilicon compounds in a process exhaust stream from silicone production are removed by contacting the exhaust stream with a semipermeable silicone membrane which is selectively permeable to organosilicon compounds and oxygen relative to nitrogen. The pressure on the permeate side of the membrane is preferably less than the pressure on the retentate side.

Organosilicon compounds in a process exhaust stream from silicone production are removed by contacting the exhaust stream with a semipermeable silicone membrane which is selectively permeable to organosilicon compounds and oxygen relative to nitrogen. The pressure on the permeate side of the membrane is preferably less than the pressure on the retentate side.

Aluminum chloride is separated from a silane mixture containing aluminum chloride by reacting the aluminum chloride with a compound reactive therewith which forms an ionic liquid or solid, and separating the ionic liquid or solid from the now-purified silane.

Aluminum chloride is separated from a silane mixture containing aluminum chloride by reacting the aluminum chloride with a compound reactive therewith which forms an ionic liquid or solid, and separating the ionic liquid or solid from the now-purified silane.

The present invention provides a novel method for preparing an aminosilane-based compound, by which an aminosilane-based compound used for preparing a modified and conjugated diene-based polymer which shows excellent affinity with an inorganic filler in a rubber composition and increases dispersibility, may be prepared in high purity and high yield.