3027-21-2Relevant articles and documents
POLYMERIZABLE DENTAL COMPOSITION BASED ON CONDENSED SILANES
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Paragraph 0552, (2021/02/26)
The present invention relates to novel polymerizable dental compositions comprising, (A) polysiloxanes, wherein the polysiloxanes comprise a mixture of the condensates of the three silanes (a1), (a2) and (a3) and/or a cocondensate of a mixture of the three silanes (a1), (a2) and (a3) and/or a mixture of at least two of the cocondensates (a1)/(a2), (a1)/(a3) and (a2)/(a3) and/or a mixture of the condensate of one of the three silanes (a1), (a2) or (a3) with the cocondensate of the other two silanes, (B) fillers and (C) initiators and/or catalysts and/or activators for the polymerization.
Method for industrially producing dialkyl dialkoxy silane
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Paragraph 0058-0060, (2020/04/17)
The invention discloses a method for industrially producing dialkyl dialkoxy silane, which comprises the following steps: in the presence of a catalyst and a solvent A, heating brominated hydrocarbonA and metal magnesium to reflux, and initiating reaction to obtain a first reaction solution; synchronously and dropwise adding chlorinated hydrocarbon and brominated hydrocarbon B which are diluted by a solvent B into the first reaction solution, and continuing reaction to obtain a second reaction solution; dropwise adding the second reaction solution into alkyl trialkoxy silane, and carrying outreflux reaction to obtain a third reaction solution; and cooling the third reaction solution, carrying out solid-liquid separation, and finally, carrying out washing and rectifying to obtain the dialkyl dialkoxy silane. The Grignard reaction of the chlorinated hydrocarbon is promoted by utilizing the high activity of the brominated hydrocarbon, so that on one hand, the overall conversion rate ofthe Grignard reaction can be remarkably improved, byproducts are reduced, the yield of a final product is improved, and on the other hand, the production cost can be reduced.
A process for preparing high-purity methyl phenyl dimethoxy silane method
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Paragraph 0019-0022, (2017/10/06)
The invention relates to a preparation method for high-purity methylphenyl-dimethoxysilane. The preparation method is characterized in that high-purity methylphenyl-dimethoxysilane is prepared through four-step deacidification. The method comprises the following steps: 1) adding dichloromethyl phenylsilane and a hydrogen chloride absorbent into an alcoholysis enclosed agitation reactor, then slowly adding a mixed liquor of absolute methanol and a catalyst drop by drop, controlling a certain reaction temperature, carrying out reflux deacidification at a certain temperature after completion of dropwise addition, carrying out filtering after complete reaction so as to obtain a crude methylphenyl-dimethoxysilane product and recovering the tail gas--hydrogen chloride gas by using a falling film absorption system for preparation of hydrochloric acid; and 2) adding the crude methylphenyl-dimethoxysilane product into a self-made gradient high-efficiency rectifying tower bottom, controlling rectification temperature for fractionation and recovery of methanol and adjusting a reflux ratio to rectify high-quality methylphenyl-dimethoxysilane with quality reaching an international advanced level. The preparation method for methylphenyl-dimethoxysilane has the advantages of environment friendliness, cyclic utilization of resources, stable process, simple operation and product purity of more than 99.5%.
