One-step preparation method and product of polyimide open-cell foam

Abstract

The invention discloses a method and product for preparing polyimide open-cell foam by one-step method. The preparation method includes the following steps: Step 1: dissolving the corresponding mass of organic acid auxiliary agent in the polar solvent of diacid diester in proportion In the solution, stir evenly to obtain foaming slurry A; step 2: mix the catalyst, foam stabilizer and foaming agent in proportion to obtain foaming slurry B; step 3: weigh the corresponding mass of polyisocyanate as the foaming slurry Slurry C; and keep foaming slurry C at the same temperature as foaming slurry A and foaming slurry B; step 4: mix foaming slurry A, foaming slurry B and foaming slurry C , to obtain a polyimide foam intermediate; Step 5: demoulding the polyimide foam intermediate, and placing it in a blast drying oven, and then raising the temperature of the blast drying oven to 170-200°C to obtain a polyimide foam intermediate. Amine open cell foam. The invention has the characteristics of effectively improving the sound absorption performance, simplifying the production process and reducing the production cost.

Description

technical field [0001] The invention relates to a polyimide foam material and a preparation method thereof, in particular to a method and a product for preparing polyimide open-cell foam in one step. Background technique [0002] The performance of a foam depends largely on its pore structure. For example, the open-pore structure has complex internal channels and high specific surface area, which are often used for catalysis and absorption. Closed-cell foam contains a large amount of gas inside and is often used for impact resistance and heat transfer resistance. In the field of sound absorption, porous foam materials have been widely used, among which open-cell foam materials occupy a dominant position. Due to its high porosity and interpenetration between pores, the incident sound wave can easily and effectively enter the deep layer of the foam, weakening the surface reflection, and generally has better sound absorption performance at medium and high frequencies. Melami...

AI Technical Summary

Problems solved by technology

CN 109929107A discloses a polyimide sound-absorbing foam material with wedge-shaped cavity structure and its preparation method. The slope of the sound absorption curve of the material reaches 1.0-1.40kHz at 100-1000Hz -1 , but the sound absorption coefficient at the absorption peak is only 0.8-0.9, and the sound absorption coefficient in the range of 1000-6300 Hz is only stable at 0.8-0.9, compared with the sound absorption performance of melamine foam, there is a big gap

At the same time, the complex design and production process not only make the preparation process more cumbersome, but also greatly increase the density of the material, with a density of 70-140kg / m 3 , which greatly increases the production cost and cannot meet the lightweight requirements of application equipment

Therefore, the existing technology has the problems of poor sound absorption performance, complicated production process and high production cost.

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