Preparation method of organosilicone modified phenolic aerogel

Abstract

The invention discloses a preparation method of organosilicone modified phenolic aerogel, belongs to the technical field of aerogel heat insulation research, and aims to solve the problems of poor environmental protection property, complex preparation method and the like in the aerogel preparation process. The method comprises the following steps: mixing phenols, aldehydes and organosilicone in proportion, adding water to prepare a solution with the mass fraction of 20-40%, stirring for 30-90 minutes, adding acids and alkalis, controlling the pH value to be 3.5-6.5, heating to cure organosilicone phenolic aldehyde, and drying at normal pressure to obtain the organosilicone modified phenolic aldehyde aerogel. An acid-base buffer solvent is used for curing, the curing time is shorter than 24hours, solvent replacement is not needed, normal-pressure drying can be directly carried out after curing, and the preparation time of the aerogel is remarkably shortened. The adopted in-situ copolymerization method is simple, the catalyst is easy to obtain, the organosilicone, the phenols and the aldehydes are uniformly mixed, and no obvious phase separation phenomenon exists. During normal-pressure drying, micron pore passages formed by the aerogel can resist the surface tension of water, so that the aerogel is in an original shape.

Description

technical field [0001] The invention belongs to the technical field of airgel heat insulation research, and in particular relates to a preparation method of organosilicon-modified phenolic airgel. Background technique [0002] Airgel is a new type of material, because of its porosity, low density, and three-dimensional network pore structure, it has many unique properties, including low electrical conductivity (<1.7), low thermal conductivity (<0.02W / m.k), Low sound propagation velocity (<100m / s), low density (<100kg / m 3 ), etc., have many applications in the fields of heat insulation, catalysis, sound insulation and so on. [0003] The most studied inorganic airgel is SiO 2 airgel, but SiO 2 The airgel can only be used at a temperature below 800°C. When the temperature is too high, the sintering shrinkage of the silica will destroy the three-dimensional pore structure of the airgel, making the airgel lose its heat insulation effect. The most studied organic ...

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Problems solved by technology

[0007] The purpose of the present invention is to provide a method for preparing organosilicon-modified phenolic airgel in order to solve the problems of poor environmental protection and complicated preparation methods in the airgel preparation process. In this method, a buffer catalyst is designed and used, and the prepared aircondensation The hydrophobic glue can be dried under normal pressure, has a certain heat insulation effect, and at the same time improves the residual carbon rate and hydrophobic heat resistance of phenolic resin

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