A kind of surface graft modification method of silicon dioxide

Abstract

The invention relates to a silicon dioxide surface grafting modification method, and aims at insufficient atomic coordination number on silicon dioxide surface, high surface energy and easy agglomeration. An epoxy silane coupling agent and ammonia water react on the silicon dioxide surface in an alkaline environment to improve the dispersibility and compatibility with polymer; the silicon dioxide surface is subjected to grafting modification with a hindered amine antioxidant; the grafting modified silicon dioxide is nano powder particles with diameter no more than 30 nm; and the the purity of product is high up to 97.6%. the preparation process has advanced strict process and accurate data; the grafting modified silicon dioxide can be used as the additive for polyphenylene sulfide composite material, can well improve and the dispersibility and compatibility with polyphenylene sulfide matrix, and can improve processability and thermal oxidation resistance performance in fiber preparation and application.

Description

technical field [0001] The invention relates to a surface graft modification method of silicon dioxide, which belongs to the technical field of material processing modification and application. Background technique [0002] Polyphenylene sulfide, referred to as PPS, PPS is a linear macromolecule composed of benzene rings connected to sulfur atoms at the para position; because the rigid ring structure of the benzene ring π bond and the sulfur atom are bonded to form a chain structure, it has excellent Performance; Since the carbon-sulfur bond in the PPS macromolecular structure has the smallest bond level, it is the weak link in the macromolecular chain; during the forming process of PPS fibers, the sulfur atoms in the structure are easy to combine with the oxygen atoms in the environment, making its material The loss of strength and its strong brittleness seriously affect its processing performance and product quality, so it is necessary to add nano-reinforced materials to P...

AI Technical Summary

Problems solved by technology

[0004] Nano-silica, commonly known as white carbon black, is a widely used nano-material with good chemical, physical and mechanical properties. However, due to the insufficient coordination number of atoms on the surface of silica and the high surface energy, these atoms are easily Agglomerates with other particles, and there are a large number of hydroxyl groups and unsaturated residual bonds on the surface of nanomaterials, showing strong hydrophilicity. When compounded with polymers, its dispersion and compatibility are poor, making nano-silica application is very limited

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