Nanosized silica thermal insulation material and preparation method based on normal-temperature drying wet process thereof

Abstract

The invention discloses a nanosized silica thermal insulation material and a preparation method based on a normal-temperature drying wet process thereof. The method comprises the following steps: adding nano silica powder, a ceramic powder opacifying agent, a xonotlite whisker or other enhanced fibers or whiskers subjected to hydrophobic treatment to a container with a water solution containing a binder; adding a foaming agent to rapidly agitate into even foam; carrying out suction filtration to obtain concentrated foam slurry; finally, orderly carrying out filter-pressing molding and normal-temperature drying on the concentrated foam slurry, so as to obtain the nanosized silica thermal insulation material. The method disclosed by the invention has the advantages of being short in production cycle (one day in general), simple in process, low in cost, and easy for realization of mechanical large-scale production. The nanosized silica thermal insulation material prepared by using the method has heat preservation and heat insulation performances similar to a monox aerogel thermal insulation material, the heat conductivity coefficient at 100 DEG C is smaller than 0.02W / m.K, and the heat conductivity coefficient below 700 DEG C is smaller than 0.05W / m.K.

Description

technical field [0001] The invention belongs to the technical field of heat insulation and heat preservation materials, and in particular relates to a nano-silicon oxide heat insulation and heat preservation material prepared by a normal-temperature dry-wet process. Background technique [0002] At present, the high temperature resistant heat insulation materials used in the field of heat insulation and heat preservation technology are mainly microporous ceramic materials with pore diameters ranging from a few microns to a few millimeters, prepared from ceramic fibers, whiskers, ceramic hollow microspheres or hollow spheres. (Zhang Lijie, Porous SiO 2 Preparation and Characterization of Base Blocks, Master Thesis of Beihang University, 2010, 11-14). The room temperature thermal conductivity of these materials is usually greater than 0.04W / m·K, and the thermal insulation performance is far from meeting the needs of some application fields that require high-efficiency thermal...

AI Technical Summary

Problems solved by technology

However, silica airgel materials need to be prepared by sol-gel and supercritical drying processes, and the production cycle is long and the cost is high, which affects its wide application.

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