Liquid butadiene-acrylonitrile rubber with epoxy group and preparation method thereof

Abstract

The invention discloses liquid butadiene-acrylonitrile rubber with an epoxy group and a preparation method thereof. The preparation method comprises the following steps: firstly, synthesizing butadiene-acrylonitrile latex from butadiene, acrylonitrile and an unsaturated monomer with an epoxy group through emulsion polymerization; then condensing, washing, drying and dehydrating the butadiene-acrylonitrile latex to obtain the liquid butadiene-acrylonitrile rubber with the epoxy group. In the synthesizing stage of the butadiene-acrylonitrile latex, 25 to 40 parts by weight of acrylonitrile and 55 to 74 parts by weight of butadiene are added, and a molecular weight regulator is selected from any one or more of ethylhexyl 3-mercaptopropionate, isooctyl 3-mercaptopropionate, tetra(3-mercaptopropionate) pentaerythritol ester or dodecyl mercaptan. The invention further discloses the liquid butadiene-acrylonitrile rubber with the epoxy group synthesized by the method. The preparation method has the advantages that the liquid butadiene-acrylonitrile rubber with the epoxy group is synthesized with a one-step process, so that the production process flow is simplified, resin curing modification at a low temperature is realized, the modifying effect is improved greatly, and the application range of the product is enlarged.

Description

technical field [0001] The invention relates to the technical field of liquid nitrile rubber, more specifically to a liquid nitrile rubber with epoxy groups and a preparation method thereof. Background technique [0002] Nitrile rubber is a kind of polymer rubber material formed by emulsion polymerization of butadiene and acrylonitrile as monomers. Because of its nitrile structure, its products have good heat resistance and oil resistance, and are widely used Used in oil-resistant rubber products, such as sealing rings, gaskets, oil-resistant hoses and other fields. According to its different states, nitrile rubber mainly includes bulk nitrile rubber, powdered nitrile rubber and liquid nitrile rubber. Among them, liquid nitrile rubber can form molecular level with other liquid resins due to its good fluidity and dispersion. It has excellent toughening and modification effect, and when mixed with epoxy resin, it can also improve its peel strength and impact strength. [000...

AI Technical Summary

Problems solved by technology

Through this method, the epoxy resin will eventually achieve the desired modification effect, but there are the following problems: (1) The reaction temperature between the carboxyl group and the epoxy group is very high, usually higher than 100 ° C, which makes the epoxy resin The application is limited because many of them are cured below 100°C or at room temperature; (2) The reaction time is relatively long, generally 2-6 hours; (3) Reaction at high temperature, in order to prevent the crosslinking of the molecule itself, it is necessary to Only in a closed nitrogen atmosphere and adding a suitable catalyst can the reaction be relatively complete

Due to the high viscosity of liquid nitrile rubber, in the subsequent reaction, it is necessary to add a large amount of solvent to dissolve it before it can react, and the solvent must be recovered later, and the process flow is relatively complicated.