- The Hydrolysis/Condensation Behaviour of Methacryloyloxyalkylfunctional Alkoxysilanes: Structure-Reactivity Relations
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Various methacryloyloxymethylalkoxysilanes have been synthesized by nucleophilic substitution reactions starting from chloromethylalkoxysilanes under phase transfer catalysis conditions. The compounds thus obtained show an exceptionally high degree of reactivity with regard to hydrolysis and condensation both under acidic as well as under basic conditions compared to the established 3-methacryloyloxypropyltrimethoxysilane. A mechanistic model for this high reactivity by intramolecular activation is discussed.
- Altmann, Stefan,Pfeiffer, Juergen
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- POLYMERIZABLE DENTAL COMPOSITION BASED ON CONDENSED SILANES
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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.
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Paragraph 0546-0548
(2021/02/26)
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- gamma-methacryloxypropylmethyldimethoxysilane preparation method
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The invention relates to a gamma-methacryloxypropylmethyldimethoxysilane preparation method, which comprises: dissolving a polymerization inhibitor in DMF in advance; adding gamma-chloropropylmethyldimethoxysilane and DMF when a synthesis kettle is preheated to a temperature of 50-60 DEG C; adding a quaternary phosphorus catalyst and a sodium salt when slowly heating to a temperature of 90-100 DEGC, uniformly stirring, and carrying out thermal insulation for 50-60 min at a temperature of 110-120 DEG C; cooling the obtained product, introducing into a centrifuge, and filtering to obtain crudegamma-methacryloxypropylmethyldimethoxysilane and a sodium salt; drying the sodium, and packaging; and carrying out coarse distillation on the crude gamma-methacryloxypropylmethyldimethoxysilane to recover DMF, introducing into a fine distillation kettle, carrying out pressure reducing distillation, and collecting the product. According to the present invention, the preparation method uses the condensation method, and has characteristics of simple operation, stable process, high production efficiency, low production cost and low environment pollution.
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Paragraph 0075-0083
(2019/11/29)
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- 4-HYDROXYPHENYLALKYLAMINE DERIVATIVE
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The present invention relates to a compound represented by the following general formula (I): wherein R1 and R2 independently represent a monovalent hydrocarbon group; R3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; X represents a divalent hydrocarbon group; and R4, R5 and R6 independently represent a monovalent organic group or a group represented by the following general formula (II): in which R7 and R8 independently represent a monovalent hydrocarbon group; and R9 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, with the proviso that R5 and R6 may combine together to form a divalent hydrocarbon group. The aforementioned compounds are useful as a polymerization inhibitor and the like.
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Page/Page column 13
(2010/10/01)
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