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CN-121991391-A - Hydrophobic photocatalytic epoxy resin/carbon fiber composite material and preparation method thereof

CN121991391ACN 121991391 ACN121991391 ACN 121991391ACN-121991391-A

Abstract

The invention discloses a hydrophobic photocatalytic epoxy resin/carbon fiber composite material and a preparation method thereof. The method comprises the steps of pre-treating a base material, constructing a nano TiO 2 /epoxy composite layer on the surface of a pre-treated sample, respectively preparing low-concentration KH560 solution and high-concentration KH560 solution, firstly immersing the sample in the low-concentration KH560 solution for treatment, then immersing in the high-concentration KH560 solution for treatment to form a gradient concentration layer with gradually increased concentration from inside to outside, then carrying out ultraviolet light assisted grafting treatment, and finally carrying out solidification by adopting a discontinuous solidification process of sectional heating and natural cooling. According to the invention, KH560 and TiO 2 form chemical bonding through gradient concentration design, and interface bonding strength and hydrophobic performance are obviously improved by combining ultraviolet light treatment and intermittent curing process. The surface water contact angle of the composite material prepared by the invention can reach more than 114 degrees, and the photocatalytic activity is kept good, so that the composite material can be widely applied to the fields of ocean engineering, aerospace, new energy automobiles and the like.

Inventors

  • YAO DAHU
  • LI MINGXU
  • GAO XIPING
  • LU CHANG
  • CHEN JING
  • PANG XINCHANG
  • Huo Pengxiang

Assignees

  • 河南科技大学

Dates

Publication Date
20260508
Application Date
20260305

Claims (10)

  1. 1. The preparation method of the hydrophobic photocatalytic epoxy resin/carbon fiber composite material is characterized by comprising the following steps of: (1) Cleaning, preprocessing and drying an epoxy resin/carbon fiber composite material sample; (2) Dispersing nano TiO 2 in the mixed solution of epoxy resin/curing agent, coating the mixture on the surface of the pretreated sample, and pre-curing to form a nano TiO 2 /epoxy composite layer; (3) Preparing a low-concentration KH560 solution and a high-concentration KH560 solution respectively, firstly immersing the sample obtained in the step (2) into the low-concentration KH560 solution for treatment, and then immersing the sample into the high-concentration KH560 solution for treatment, so as to form a KH560 gradient concentration layer with gradually increased concentration from inside to outside on the surface of the nano TiO 2 /epoxy composite layer; (4) Placing the sample obtained in the step (3) under ultraviolet light for irradiation treatment; (5) And (3) carrying out intermittent solidification on the sample obtained in the step (4), wherein the intermittent solidification comprises at least two heating sections and cooling sections inserted between the heating sections.
  2. 2. The method of claim 1, wherein in step (2), the curing agent is D230; The particle size of the nano TiO 2 is 20-50nm; the mass ratio of the nano TiO 2 to the epoxy resin/curing agent mixed solution is 0.2-0.8:2.
  3. 3. The method according to claim 1, wherein in the step (2), the mass ratio of the epoxy resin to the curing agent is 2:1, the pre-curing temperature is 75-85 ℃ and the time is 1.5-2.5h.
  4. 4. The method according to claim 1, wherein in the step (3), the low-concentration KH560 solution is prepared by adding 20ml of absolute ethyl alcohol and 0.05-0.15g of deionized water into 0.1-0.3g of KH560, adjusting pH to 3-4 with glacial acetic acid, and hydrolyzing in a water bath at 35-45 ℃ for 10-20 min.
  5. 5. The method according to claim 4, wherein in the step (3), the high-concentration KH560 solution is prepared by adding 20ml of absolute ethyl alcohol and 0.25-0.35g of deionized water into 0.6-1.0g of KH560, adjusting the pH to 3-4 with glacial acetic acid, and hydrolyzing in a water bath at 35-45 ℃ for 50-70 min.
  6. 6. The method of claim 5, wherein in step (3), the mass ratio of KH560 in the low concentration KH560 solution to KH560 in the high concentration KH560 solution is 1:2 to 1:6.
  7. 7. The method according to claim 1, wherein in the step (3), the treatment time of immersing in the low-concentration KH560 solution is 5-8min, the treatment time of immersing in the high-concentration KH560 solution is 3-5min, and the treatment time of immersing in the high-concentration KH560 solution is 8-12min at room temperature between two dips.
  8. 8. The method according to claim 1, wherein in the step (4), the ultraviolet light is irradiated at a wavelength of 365nm, a power of 400-600W, a distance of 8-12cm and an irradiation time of 15-30min.
  9. 9. The method of claim 1, wherein in step (5), the intermittently curing comprises: The first stage is that drying is carried out for 3-5h at 75-85 ℃, natural cooling is carried out to room temperature, and the drying is carried out for 1.5-2.5h; the second stage is to heat up to 95-105 ℃ at 0.3-0.8 ℃ per min, keep the temperature for 0.5-1.5h, naturally cool to room temperature, and place for 1.5-2.5h; And in the third stage, heating to 115-125 ℃ and curing for 3-5h.
  10. 10. A hydrophobic photocatalytic epoxy resin/carbon fiber composite material, characterized in that it is prepared by the method according to any one of claims 1 to 9.

Description

Hydrophobic photocatalytic epoxy resin/carbon fiber composite material and preparation method thereof Technical Field The invention belongs to the technical field of composite material surface modification, and particularly relates to an epoxy resin/carbon fiber composite material capable of realizing hydrophobic and photocatalytic degradation functions through interface reaction regulation and control and a preparation method thereof. Background The epoxy resin/carbon fiber composite material has been widely applied to the high-end manufacturing fields of aerospace, new energy automobiles, wind power blades and the like by virtue of excellent performances such as light weight, high strength, chemical corrosion resistance and the like. Along with the expansion of application scenes to complex environments such as oceans, outdoor and the like, the surface of the composite material is easy to absorb water vapor and organic pollutants, so that the appearance is neat, the interface aging and performance attenuation can be accelerated, and the service life of the composite material under severe working conditions is severely restricted. Titanium dioxide (TiO 2) has wide application in the fields of self-cleaning, corrosion prevention and the like by virtue of excellent chemical stability and photocatalytic activity. The TiO 2 and silane coupling agent composite modified epoxy resin/carbon fiber composite material can endow the surface of the composite material with hydrophobic and photocatalytic functions on the premise of not changing the mechanical properties of the substrate body. In the prior art, methods for modifying the surface of a material after mixing TiO 2 and a silane coupling agent are reported, but the methods generally adopt a one-time coating process, and have the defects that firstly, the mixed solution of the silane coupling agent and TiO 2 is difficult to realize sufficient bonding with TiO 2 and complete coverage of the surface by the silane coupling agent in the coating process, secondly, the photocatalytic activity of TiO 2 can indifferently oxidize organic resin contacted with the organic resin to cause interface aging, and thirdly, the traditional continuous curing process is easy to generate thermal stress in the coating to influence the durability of the coating. Therefore, how to improve the interfacial bonding strength and the hydrophobic durability through process optimization is still a technical problem to be solved in the art. Disclosure of Invention Aiming at the technical defects of weak interface bonding, incomplete hydrophobic layer and insufficient durability in the surface modification of the composite material in the prior art, the hydrophobic photocatalytic epoxy resin/carbon fiber composite material and the preparation method thereof are provided. In order to achieve the above purpose, the invention adopts the following specific scheme: In a first aspect, the invention provides a preparation method of a hydrophobic photocatalytic epoxy resin/carbon fiber composite material, comprising the following steps: (1) Cleaning, preprocessing and drying an epoxy resin/carbon fiber composite material sample; (2) Dispersing nano TiO 2 in the mixed solution of epoxy resin/curing agent, coating the mixture on the surface of the pretreated sample, and pre-curing to form a nano TiO 2/epoxy composite layer; (3) Preparing a low-concentration KH560 solution and a high-concentration KH560 solution respectively, firstly immersing the sample obtained in the step (2) into the low-concentration KH560 solution for treatment, and then immersing the sample into the high-concentration KH560 solution for treatment, so as to form a KH560 gradient concentration layer with gradually increased concentration from inside to outside on the surface of the nano TiO 2/epoxy composite layer; (4) Placing the sample obtained in the step (3) under ultraviolet light for irradiation treatment; (5) And (3) carrying out intermittent solidification on the sample obtained in the step (4), wherein the intermittent solidification comprises at least two heating sections and cooling sections inserted between the heating sections. Further, in the step (2), the curing agent is D230; The particle size of the nano TiO 2 is 20-50nm; the mass ratio of the nano TiO 2 to the epoxy resin/curing agent mixed solution is 0.2-0.8:2. Further, in the step (2), the mass ratio of the epoxy resin to the curing agent is 2:1, the pre-curing temperature is 75-85 ℃ and the time is 1.5-2.5h. Further, in the step (3), the preparation method of the low-concentration KH560 solution comprises the following steps: adding KH560 0.1-0.3g into absolute ethanol 20ml and deionized water 0.05-0.15g, adjusting pH to 3-4 with glacial acetic acid, and hydrolyzing in 35-45deg.C water bath for 10-20 min. Further, in the step (3), the preparation method of the high-concentration KH560 solution comprises the following steps: Adding 20ml of absolute ethyl alcohol a