Method for preparing prepreg through regulating and controlling viscosity of epoxy resin system and fluidity of prepreg by chemorheology

Abstract

The invention provides a method for preparing a prepreg through regulating and controlling viscosity of an epoxy resin system and fluidity of the prepreg by chemorheology. According to the method, a mixed curing agent of a room temperature reactive curing agent and a latent curing agent is adopted, and the epoxy resin system with low viscosity for the prepreg is prepared through the initial chemical reaction of the mixed curing agent and the epoxy resin component; adhesive films are prepared from the resin system by a film forming machine, then the adhesive films and reinforced fibers or fabric are compounded through a compound machine, and the prepreg with excellent dipping characteristic is prepared; the prepreg is placed at room temperature so that the fluidity of the prepreg is regulated and controlled, and the prepreg with good technological operation property and joint property is obtained. Compared with traditional manufacture technique of the prepreg, the method can guarantee that the reinforced fibers can be dipped in the epoxy resin with low viscosity, and every single monofilament can be dipped completely; and through following-up chemical reaction at room temperature, the grease fluidity of the prepared prepreg can be lowered, so that the technological requirements of composite material forming can be met.

Description

technical field [0001] The invention relates to the field of composite materials, in particular to a preparation method for controlling the viscosity of an epoxy resin system and the fluidity of a prepreg by means of chemical rheology. Background technique [0002] Prepreg is a resin matrix impregnated with continuous fibers or fabrics under strictly controlled process conditions to make a composition of resin matrix and reinforcing fibers, and is an intermediate material for preparing composite materials. Since the performance of composite materials depends largely on the performance of prepregs, the quality of prepregs is of great significance to the application and development of composite materials. In order to improve the quality control of the prepreg, it is necessary to adjust the adhesive performance of the prepreg by controlling the viscosity of the matrix resin. First, the viscosity of the matrix resin should be low enough so that the matrix can fully infiltrate ea...

AI Technical Summary

Problems solved by technology

[0003] In order to control the fluidity of the resin, the general method is to add nitrile rubber, liquid or solid carboxy-terminated nitrile rubber, thermoplastics, etc. to the epoxy resin system for prepregs. These components reduce the fluidity of the resin system while , which also improves the toughness of the resin system, but at the same time it also leads to an increase in the viscosity of the resin system, so the wettability of the reinforcing fiber becomes poor

Chinese patent (CN101947859) discloses a production method of staged prepregs. Compared with traditional prepregs, this method needs to be placed at a low temperature for a period of time to complete the precuring reaction to meet the hardness requirements of prepregs, but it does not involve To the formulation components and viscosity requirements of the epoxy resin system for prepregs, and placing it at low temperature is relatively energy-consuming

However, the polybutylene glycol glycidyl ether diluent is added to the resin system to reduce the viscosity, which will affect the final performance of the composite material. The important thing is that the patent is for wet winding prepregs, which are not suitable for wide application at present. The hot-melt two-step prepreg production process

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