Method for toughening composite interlayers by using multiwalled carbon nanotubes

Abstract

The invention belongs to the fields of preparation and mechanical properties of carbon fiber / resin-based laminated composite materials, and relates to a method for toughening composite interlayers byusing multiwalled carbon nanotubes (MWCNTs). The method comprises the steps that the multiwalled carbon nanotubes low in cost are used as a toughening material for the composite prepreg interlayers, after cutting of prepreg is completed, the multiwalled carbon nanotubes are quantitatively put into acetone or ethyl alcohol liquid in proportion, fully dispersed through ultrasonic waves and uniformlysprayed to the surface of each layer of the prepreg by using an air pressure gun, after the acetone or the ethyl alcohol is completely volatilized, the prepreg is laid and then fed into a hot-press tank for heating and pressurizing solidification, and finally, the prepreg is cut into DCB and ENF standard samples for I and II fracture toughness testing. The testing results show that when the spraying surface density is 1 g / m<2>, GIC and GIIC of the material are remarkably improved, the interlayer toughness of a composite laminated structure is improved, and the deficiency of the interlayer performance of the laminated composite material is made up for.

Description

technical field [0001] The invention belongs to the technical preparation field of thermosetting carbon fiber / resin-based composite materials, in particular to a method for preparing multi-walled carbon nanotubes (MWCNTs) for interlayer toughening of resin-based continuous fiber composite materials. Background technique [0002] At present, resin-based continuous fiber composite materials are widely used in the aviation field, and have the advantages of high specific stiffness and specific strength, fatigue resistance, and corrosion resistance. For example, the structural dosage of Boeing 787 reaches more than 50%. Resin-based continuous fiber prepreg composites are used as materials for the surface structure of aircraft. They are prone to delamination when they are impacted, which greatly reduces the load-bearing capacity of the structure used. Therefore, resin-based continuous fiber prepreg composites are toughened between layers. Improve its anti-delamination ability. ...

AI Technical Summary

Problems solved by technology

This method obtains better interlayer performance, but the process is still relatively complicated, and at the same time, dissolving nanomaterials in resin will change the stiffness and strength in the prepreg layer; and only G is tested in this application IC , not documented for other materials such as G IIC detection

[0004] Chinese patent (CN104945852A) discloses a micro-nanoparticle interlayer toughening technology. First, the mixed solution of micronanoparticles and inorganic particles is evenly sprayed on the fiber, and then placed in an oven for drying treatment. Composite with a thermosetting resin to prepare a composite material with interlayer toughening of micro-nano particles. Although this method significantly improves the interlayer fracture toughness of the composite material, the molding process is more complicated and the cost is high. It needs to be sprayed on the fiber first. Change the interfacial bonding strength of the material itself, and do not use carbon nanotube materials with super performance in recent years

Images