Preparation method of graphene-sulfur microcapsule composite

Abstract

The invention relates to a preparation method of a graphene-sulfur microcapsule composite, comprising: first, introducing organic molecules of hydroxy, sulfydryl, amino, carboxy or other groups to thesurface of graphene oxide by means of physical adsorption or chemical grafting; second, preparing graphene-coated sulfur microcapsule by means of mechanical blending. A core material is common sulfur, and the surface of the core material is subjected to graphene oxide or graphene modification to form a core-shell structure. The graphene shell herein can effectively enclose the sulfur therein, andblooming during rubber processing is inhibited; the rich functional groups on the surface or edge of the graphene enable the sulfur to be evenly dispersed in a rubber base during mixing stage and engage in sulfurization reaction during sulfurization stage, thermal stability of the sulfur is improved, and excellent properties are imparted to the composite. The prepared graphene-sulfur microcapsulecomposite has high purity, good thermal stability, high coating rate, high sulfur utilization rate and low cost.

Description

technical field [0001] The invention relates to the field of preparation of functionalized vulcanizing agents, in particular to a method for preparing a graphene sulfur microcapsule composite material applied to rubber. Background technique [0002] Sulfur is the earliest vulcanizing agent used in rubber crosslinking. It is widely used in industry due to its low price, good elasticity and fatigue resistance of vulcanized rubber. However, ordinary sulfur is easy to agglomerate in rubber, and it is difficult to achieve uniform distribution. At the same time, the solubility of sulfur in rubber varies with temperature. Precipitation in the rubber, resulting in blooming phenomenon, which will produce or aggravate the phenomenon of uneven dispersion of sulfur in the rubber matrix, seriously affect the cohesiveness of rubber, and reduce its performance; in addition, sulfur has certain toxicity, especially after being heated. Sulfur vapor and sulfur dioxide produced after oxidation...

AI Technical Summary

Problems solved by technology

However, for sulfur particles, its affinity for macromolecules or polymers is extremely low, and most of them are deposited on the surface through physical adsorption. Therefore, styrene monomers are easy to nucleate in the liquid phase alone to synthesize their own Macromolecular microspheres, which eventually lead to poor coverage

In addition, the process of generating sulfur from sodium thiosulfate pentahydrate is accompanied by the generation of harmful gas sulfur dioxide, which is harmful to the environment and the body, and the generated impurities such as sodium chloride are not easy to remove, which affects the performance of polystyrene-coated sulfur microcapsules

At this stage, the effect of sulfur coating is not particularly ideal, and there are various problems, such as: high impurities, low coating rate, insufficient strength of the capsule wall material, resulting in rupture and release of sulfur during the mixing stage, or the capsule wall material is vulcanized. stage cannot release sulfur, resulting in inability to cross-link, etc.