Search

CN-122011687-A - High-toughness epoxy resin-based carbon fiber prepreg and preparation method thereof

CN122011687ACN 122011687 ACN122011687 ACN 122011687ACN-122011687-A

Abstract

The invention relates to the technical field of polymer composite materials, in particular to a high-toughness epoxy resin-based carbon fiber prepreg and a preparation method thereof. The prepreg comprises carbon fiber, synergistic modified epoxy resin, 2, 6-dihydroxytriptycene, a curing agent, an accelerator, a thermoplastic toughening agent, a rheology modifier and a nano filler. The preparation method comprises the steps of forming a host-guest inclusion structure through hydroxypropyl-beta-cyclodextrin and 1-adamantanemethylamine, forming a dynamic borate bond through 3-aminophenylboric acid and tannic acid, introducing octa (glycidyl ether propyl) silsesquioxane to construct a cage-shaped rigid node, carrying out synergistic modification on bisphenol F-type epoxy resin and tetrafunctional glycidol amine-type epoxy resin, and constructing a three-dimensional dynamic cross-linked network structure to obtain the synergistic modified epoxy resin. Through the multi-structure synergistic effect and the combination of the regulation and control of the 2, 6-dihydroxytriptycene on the interface, the interlaminar shear strength, the impact strength and the fracture toughness of the prepreg can be obviously improved, and meanwhile, the interface bonding performance between the carbon fiber and the resin matrix is enhanced.

Inventors

  • WANG DAJUN
  • LIU WEIBIAO

Assignees

  • 江苏美伦新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20260316

Claims (10)

  1. 1. The high-toughness epoxy resin-based carbon fiber prepreg is characterized by comprising, by weight, 80-150 parts of carbon fibers, 70-100 parts of co-modified epoxy resin, 0.3-4 parts of 2, 6-dihydroxytriptycene, 20-45 parts of a curing agent, 0.2-2 parts of an accelerator, 2-12 parts of a thermoplastic toughening agent, 0.2-3 parts of a rheology regulator and 0.5-5 parts of a nano filler, wherein the co-modified epoxy resin forms a host-guest inclusion structure through hydroxypropyl-beta-cyclodextrin and 1-adamantanemethylamine, forms a dynamic boric acid ester bond through 3-aminophenylboric acid and tannic acid, and simultaneously introduces octa (glycidyl ether propyl) silsesquioxane to construct a cage-shaped rigid node, and synergistically constructs a three-dimensional dynamic cross-linking network for bisphenol F-type epoxy resin and tetrafunctional glycidyl amine-type epoxy resin.
  2. 2. The high-toughness epoxy resin-based carbon fiber prepreg according to claim 1, wherein the synergistically modified epoxy resin comprises, by weight, 35-60 parts of bisphenol F epoxy resin, 10-30 parts of tetrafunctional glycidylamine epoxy resin, 0.5-4 parts of hydroxypropyl-beta-cyclodextrin, 0.2-2 parts of 1-adamantanemethylamine, 0.3-3 parts of 3-aminophenylboronic acid, 0.3-3 parts of tannic acid, 0.5-5 parts of octa (glycidyl ether propyl) silsesquioxane, and 0.3-3 parts of N- (beta-aminoethyl) -gamma-aminopropyl trimethoxysilane.
  3. 3. The high-toughness epoxy resin-based carbon fiber prepreg according to claim 1 or 2, wherein the preparation method of the synergistically modified epoxy resin comprises the following steps: (1) Mixing bisphenol F-type epoxy resin, tetrafunctional glycidol amine-type epoxy resin, hydroxypropyl-beta-cyclodextrin and 1-adamantane methylamine, and stirring to enable the hydroxypropyl-beta-cyclodextrin and the 1-adamantane methylamine to form a host-guest inclusion structure, so as to obtain a host-guest structure modified epoxy resin intermediate; (2) Adding 3-aminophenylboric acid and tannic acid into the main guest structure modified epoxy resin intermediate and reacting to form a dynamic borate structure, so as to obtain a dynamic borate network modified epoxy resin intermediate; (3) And adding octa (glycidyl ether propyl) silsesquioxane and N- (beta-aminoethyl) -gamma-aminopropyl trimethoxy silane into the intermediate of the dynamic borate network modified epoxy resin, and reacting to obtain the synergistic modified epoxy resin.
  4. 4. The high-toughness epoxy resin-based carbon fiber prepreg according to claim 3, wherein the reaction condition in the step (1) is that the reaction is carried out at 65-85 ℃ under the protection of nitrogen, the stirring speed is 300-500 rpm, and the reaction time is 1-2 h.
  5. 5. The high-toughness epoxy resin-based carbon fiber prepreg according to claim 3, wherein the reaction condition of the step (2) is that the reaction is carried out at 70-90 ℃, the pH of the system is 7.5-9.0, the stirring speed is 300-600 rpm, and the reaction time is 1.5-3 h.
  6. 6. The high-toughness epoxy resin-based carbon fiber prepreg according to claim 3, wherein the reaction condition of the step (3) is that the reaction is carried out at 75-95 ℃, the stirring speed is 400-700 rpm, and the reaction time is 1-3 h.
  7. 7. The high-toughness epoxy resin-based carbon fiber prepreg is characterized in that the curing agent is formed by mixing (3-8) of 4,4' -diaminodiphenyl sulfone and (2-5) of diaminodiphenyl methane in mass ratio, the accelerator is formed by mixing (1-4) of 2-methylimidazole and (1-3) of 2-ethyl-4-methylimidazole in mass ratio, the thermoplastic toughening agent is formed by mixing (4-10) of polyethersulfone and polyamideimide in mass ratio (1-4), the rheology regulator is formed by mixing (2-6) of fumed silica and polyamide wax in mass ratio (1-3), and the nanofiller is formed by mixing (3-8) of nano silica and nano alumina in mass ratio (1-4).
  8. 8. The preparation method of the high-toughness epoxy resin-based carbon fiber prepreg is characterized by comprising the following steps of: S1, mixing and stirring and dispersing synergistically modified epoxy resin, 2, 6-dihydroxytriptycene, a thermoplastic toughening agent, a rheology regulator and nano fillers to obtain a modified epoxy resin matrix mixture; s2, adding a curing agent and an accelerator into the modified epoxy resin matrix mixture and mixing to obtain a presoaked resin system; S3, impregnating the carbon fibers in a prepreg resin system, enabling the resin to uniformly infiltrate the carbon fibers, and performing pre-curing treatment after the resin content is regulated by scraping, so as to obtain the high-toughness epoxy resin-based carbon fiber prepreg.
  9. 9. The preparation method of the high-toughness epoxy resin-based carbon fiber prepreg according to claim 8 is characterized in that the reaction condition of the step S1 is stirring and dispersing at 60-80 ℃, the stirring speed is 400-700 rpm, the dispersing time is 0.5-1.5 h, the reaction condition of the step S2 is mixing and stirring at 50-70 ℃, the stirring speed is 300-600 rpm, and the mixing time is 0.5-1 h.
  10. 10. The method for preparing the high-toughness epoxy resin-based carbon fiber prepreg according to claim 8, wherein the reaction condition in the step S3 is that the carbon fiber is immersed at 50-70 ℃ in a resin system for 3-10 min, the pre-curing temperature is 80-110 ℃, and the pre-curing time is 5-20 min.

Description

High-toughness epoxy resin-based carbon fiber prepreg and preparation method thereof Technical Field The invention relates to the technical field of polymer composite materials, in particular to a high-toughness epoxy resin-based carbon fiber prepreg and a preparation method thereof. Background The carbon fiber reinforced epoxy resin composite material has the characteristics of high specific strength, high specific modulus, good corrosion resistance, excellent dimensional stability and the like, and is widely applied to the fields of aerospace, wind power blades, rail transit, automobile weight reduction, high-end equipment manufacturing and the like. The performance of carbon fiber prepregs as important intermediate materials for preparing carbon fiber composite materials depends largely on the structural properties of the epoxy resin matrix and the interfacial bonding state between the carbon fibers and the resin. The epoxy resin-based carbon fiber prepreg system commonly used at present mostly adopts bisphenol A type or bisphenol F type epoxy resin as matrix resin, and forms a highly crosslinked three-dimensional network structure after being cured by a curing agent. Although the structure can endow the composite material with higher strength and modulus, the epoxy resin has higher crosslinking density and limited molecular chain segment movement capability after being cured, so that the whole material has obvious brittleness characteristic, and is easy to crack and rapidly expand when being impacted or concentrated in stress, thereby causing the problems of interlayer stripping, interface failure and the like, and seriously affecting the use reliability and durability of the composite material. In order to improve the toughness of the epoxy resin system, the prior art generally adopts methods such as rubber toughening, thermoplastic resin toughening or nanoparticle modification. However, the heat resistance and modulus of the material are often reduced by toughening the rubber, the viscosity of the system is easily increased by toughening the thermoplastic resin, the wettability and the process stability of the prepreg are affected, and the nano filler has poor dispersibility, limited interfacial bonding capability and certain limitation on the toughening effect although the mechanical property can be improved to a certain extent. The traditional modification method focuses on toughening of a single structure or a single mechanism, and is difficult to simultaneously consider the toughness, the interface bonding strength and the structural stability of the material. Therefore, a modified epoxy resin system which can remarkably improve toughness and improve the interfacial bonding performance of carbon fibers and resin while maintaining high strength and high modulus of the epoxy resin system is developed, so that the high-performance carbon fiber prepreg is prepared, and the modified epoxy resin system has important research significance and application value. Disclosure of Invention The invention aims to solve the problems that the epoxy resin-based carbon fiber prepreg in the prior art is insufficient in toughness, cracks are easy to expand and the bonding strength of a carbon fiber and a resin interface is limited. The invention provides a high-toughness epoxy resin-based carbon fiber prepreg which comprises carbon fibers, synergistically modified epoxy resin, 2, 6-dihydroxytriptycene, a curing agent, an accelerator, a thermoplastic toughening agent, a rheology modifier and a nano filler, wherein a host-guest inclusion structure is formed by hydroxypropyl-beta-cyclodextrin and 1-adamantanemethylamine, a dynamic borate bond is formed by 3-aminophenylboric acid and tannic acid, octa (glycidyl ether propyl) silsesquioxane is introduced to construct cage-shaped rigid nodes, bisphenol F-type epoxy resin and tetrafunctional glycidyl amine type epoxy resin are synergistically modified, and a three-dimensional dynamic cross-linked network structure with a host-guest sliding structure, dynamic covalent bonds and the cage-shaped rigid nodes is constructed, so that the synergistically modified epoxy resin is obtained, and is compounded with the carbon fibers and other assistants to prepare the high-toughness epoxy resin-based carbon fiber prepreg. According to the invention, by constructing a three-dimensional dynamic cross-linked network with a host-guest inclusion structure, a dynamic borate bond and a cage-shaped silsesquioxane node synergistic effect and introducing 2, 6-dihydroxytriptycene for interface regulation, the toughness and interface bonding performance of the epoxy resin-based carbon fiber prepreg can be remarkably improved, and meanwhile, the strength and structural stability of the material are maintained. The aim of the invention can be achieved by the following technical scheme: The high-toughness epoxy resin-based carbon fiber prepreg comprises, by weight, 80-150 parts of carbon fibers, 70-1