Preparation method of modified porous silicon dioxide moisture-proof anti-reflection coating

Abstract

The invention discloses a preparation method of a modified porous silicon dioxide moisture-proof anti-reflection coating. The method comprises the following steps: firstly synthesizing multi-arm silane via siloxane containing epoxy group and siloxane containing primary amine or secondary amine through ring-opening addition reaction, taking multi-arm silane and silane monomers containing siloxane as common silicon source monomers, preparing a precursor solution of polysiloxane sol under an acid catalysis condition, then preparing a pore-forming agent solution, then preparing modified silicon dioxide sol, finally carrying out one-time film formation on a transparent substrate via the modified silicon dioxide sol through a dipping-pulling method to prepare the modified porous silicon dioxidemoisture-proof anti-reflection coating. The coating has a wide-spectrum reflection reduction effect, is flat and smooth in surface, excellent in abrasion resistance and weather resistance and excellent in moisture-proof function, has tightly stacked particles, has a thickness of 100-200nm, a section pore size of 5-10nm and a surface pore size of 10-40nm, and is beneficial to reversible adsorptionand desorption of water vapor.

Description

technical field [0001] The invention belongs to the technical field of modification of inorganic thin film materials, in particular to a preparation method of a modified porous silica moisture-proof and anti-reflection coating. Background technique [0002] Silica antireflection coatings prepared based on the sol-gel method have excellent optical properties and are widely used due to their good weather resistance, adjustable refractive index, simple preparation method, and large-area preparation. However, when applied to antireflection coatings for solar cells, architectural glass and optical lenses, they are easily affected by external environmental factors, mainly including moisture adsorption, dust pollution and surface wear, etc., resulting in decreased optical performance, shortened service life, and reduced components Maintenance costs go up. [0003] At present, the silica antireflection coating prepared by the sol-gel method has initially obtained a coating surface ...

AI Technical Summary

Problems solved by technology

Among them, hybrid silica usually adopts two-step or multi-step method to obtain modified sol, the operation steps are more complicated, and the preparation method is less controllable. While the surface of the obtained coating has self-cleaning function, the roughness is relatively large and there are a large number of External porosity; and after the introduction of a large number of functional groups in the coating, the effective condensation sites of silanol groups are greatly reduced, and the degree of crosslinking is reduced. The research on the stability and mechanical wear resistance of the coating is unknown

In contrast, the existing mesoporous silica anti-reflection coating (the SEM image of its surface is shown in figure 1 ), under the premise of acid catalysis, it has a unique high-strength and ordered mesoporous network, stable structure, dense film layer, smooth surface, strong mechanical wear resistance and weather resistance, but due to the existence of mesoporous pores on the surface, it will Irreversible chemical / physical adsorption with water vapor in the air under the action of capillary condensation causes the mesoporous pore structure to swell and change. After the pores are filled with water vapor, the refractive index increases and the anti-reflection performance decreases seriously; in view of this, chemical Modified post-treatment, "closed" surface mesopores, made the surface hydrophobic, and inhibited moisture absorption

Although this method is effective, it has a short timeliness. Once the hydrophobic effect fails, the original mesoporous coating surface will absorb moisture again.

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