一种孔径连续梯度的氧化铝气凝胶及其制备方法
By constructing a longitudinal temperature gradient and active thermal compensation on the sidewalls in alumina sol, and combining this with ice recrystallization to suppress polymers, an alumina aerogel with a continuous gradient change in pore size along the thickness direction was prepared. This solved the problem of gradient forming in the prior art and improved the structural integrity and pore size control capability of the aerogel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHENGZHOU NON FERROUS METALS RES INST CO LTD OF CHALCO
- Filing Date
- 2026-05-28
- Publication Date
- 2026-07-17
AI Technical Summary
Existing technologies cannot prepare alumina aerogels with a continuous gradient of pore size along the thickness direction and a corresponding continuous change in apparent density. This cannot meet the gradient functional requirements for filtration and thermal insulation applications. Furthermore, low-density aerogel systems are prone to structural collapse and pore discontinuity during gradient molding.
By establishing a longitudinal temperature gradient in alumina sol and applying active thermal compensation to the sidewalls, combined with ice recrystallization to inhibit high molecular weight polyvinyl alcohol, the rate of solidification front advance is controlled, forming a continuous pore size gradient structure. Subsequently, freeze-drying and calcination are performed to ensure the integrity of the gradient structure.
A non-interface gradient pore structure with alumina aerogel pore size continuously decreasing from 50 to 200 μm to 1 to 20 μm was realized, which improved the structural integrity of the low-density gradient framework and enabled the electrically adjustable pore size gradient slope to meet the differentiated needs of different application scenarios.
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Figure CN122404014A_ABST