A kind of preparation method of liquid tetraketoxime base silane at room temperature

Abstract

The invention discloses a method for preparing tetrafunctional ketoximino silane in liquid state at room temperature, and aims to overcome the inconvenience brought by crystallization when tetrafunctional ketoximino silane is used for preparing quick-curing RTV silicon rubber. According to the method, diacetylmonoxime, methyl isobutyl ketoxime and No.120 solvent oil are pumped into an agitation reaction kettle as per certain proportion; under the condition of agitation, silicon tetrachloride and ammonia gas are added at the same time, the speed of adding silicon tetrachloride and ammonia gas is controlled to keep the reaction temperature at 20-80 DEG C; the reaction is stopped after completion of charging; filtration is performed to separate out a byproduct ammonium chloride so as to obtain a semi-finished product of tetrafunctional ketoximino silane; the semi-finished product is firstly placed into a first film evaporator to distil out the No.120 solvent oil, and then is placed into a second film evaporator to distil out excessive diacetylmonoxime and methyl isobutyl ketoxime, so that a product can be obtained. Tetrafunctional ketoximino silane prepared through the method has similar activity as tetrakis (methylethylketoximino) silane, and is free of crystallization at low temperature, so that the use is greatly facilitated.

Description

technical field [0001] The invention relates to the field of synthesis of silane crosslinking agents, in particular to a preparation method of liquid tetraketoxime silane at room temperature. Background technique [0002] Ketoxime-based silanes with four active functional groups are used to prepare room-temperature-cured deketoxime-type silicone rubber to improve the curing rate of the silicone rubber. Active functional groups refer to functional groups that can undergo condensation reactions, specifically various ketoxime functional groups. Other functional groups, such as methyl, vinyl, and phenyl, cannot undergo condensation reactions with water, so they have no activity. Currently, tetrabutylketoxime silane is generally used to prepare room temperature curing deketoxime silicone rubber, and its pure product It is solid at room temperature and generally needs to be dissolved in toluene or methyl tributylketoxime silane and vinyl tributylketoxime silane. However, it can ...

AI Technical Summary

Problems solved by technology

However, it can only reach 20% in the solution of methyl tributylketoxime silane and vinyl tributyl ketoxime silane, and can only reach 50% in toluene solution, and when the temperature is very low, such as 0 When the temperature is lower than ℃, crystallization will still occur

This greatly limits its use

The use of toluene solution is restricted due to the toxicity of toluene

[0003] The invention of CN102516599A discloses a synthesis method of a mixed ketoxime type crosslinking agent. Put butanone oxime and 120# solvent into the reaction kettle, add methyltrichlorosilane, butanone oxime, 120# solvent and The mass ratio of methyltrichlorosilane is 3.6: 1: 1. After the reaction is over, let it stand for stratification, remove the butanone oxime hydrochloride in the lower layer, and fill the semi-finished product with ammonia gas to obtain ammonium chloride solid salt and filter , to obtain a semi-finished product; add butanone oxime and 120# solvent to the semi-finished product, drop silicon tetrachloride under stirring, and charge into ammonia gas at the same time, filter the by-product ammonium chloride solid salt that generates after the reaction finishes, and distill , to obtain the finished product of a mixed crosslinking agent with a mass ratio of methyl tributylketoxime silane and tetrabutyl ketoxime silane of 4:1, the disadvantage of which is: it finally obtains a mixture of three active functional groups and four active functional groups , the three active functional groups are liquid, and the four active functional groups are solid, so only 20% of tetrabutanoximinosilane can be dissolved in the mixture; and when the temperature is very low, such as below 0°C, crystallization will still occur

This greatly limits its use

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