Recycling surface modification method for aluminum oxide powder high in water dispersion stability

Abstract

The invention belongs to the technical field of materials and discloses a recycling surface modification method for aluminum oxide powder high in water dispersion stability. According to the method, compound modifier generation reaction and grafting reaction of aluminum oxide powder are both carried out in organic solvents, condensation reaction of a silane coupling agent is effectively prevented, aluminum oxide surface modified molecular layers are more regular, and accordingly surface coating rate and surface modification effects of the aluminum oxide powder are controllable; aiming at waterborne media different in property, favorable compatibility and dispersion stability of the modified aluminum oxide powder in water or waterborne media can be achieved through compound modifier molecular design; appropriate solvents are selected to realize recovery and recycling of residual compound modifier, reactants and solvents, and material closed cycle, cleanness and environment friendliness (namely freeness of waste liquid generation and discharge) in a whole surface modification process are realized.

Description

technical field [0001] The invention relates to a method for surface modification of alumina powder with high water dispersion stability and belongs to the field of material technology. Background technique [0002] Alumina ultrafine powder not only has the unique properties shared by ultrafine powders, such as special electrical, magnetic and optical properties, but also has excellent properties such as high hardness, wear resistance and high temperature resistance, so it is widely used in semiconductors, ceramics , Abrasives and optical materials and other high-tech fields. However, due to the large specific surface area and surface energy of the alumina ultrafine powder, the surface is charged, and the surface groups are abundant, the agglomeration between the particles is very serious, so that it often disperses unevenly or occurs under the medium. The sinking phenomenon will affect the dispersion stability and use effect of the suspension. Therefore, improving the com...

AI Technical Summary

Problems solved by technology

Generally speaking, for relatively simple systems, a higher grafting rate is required; while for more complex systems, it is necessary to select a suitable matching polymer, and an appropriate grafting rate and degree of polymerization are required to adapt to the system. Therefore, the stable growth of the polymer is often achieved by controlling a series of process parameters, so that most of the surface grafting process has problems such as complicated process flow, long processing cycle and low efficiency.

At the same time, almost all powder modification methods involve the use of modifiers and organic solvents, but most of the residual modifiers and organic solvents in the reaction process cannot be effectively recycled, so there is an environmental pollution problem

[0005] To sum up, although the currently reported powder surface modification technologies have their own characteristics, basically there are complex powder surface modification processes, long treatment cycles, low efficiency, and grafting or coating ratios. Problems such as difficult control make the compatibility between the modified powder and the medium and the uniform dispersion stability in the medium unsatisfactory, and most of the modification methods have environmental pollution

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