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CN-122011672-A - Phosphogypsum whisker/fiber reinforced composite material and preparation method thereof

CN122011672ACN 122011672 ACN122011672 ACN 122011672ACN-122011672-A

Abstract

The invention discloses an phosphogypsum whisker/fiber reinforced composite material and a preparation method thereof, and belongs to the technical field of composite materials. The composite material comprises cashew nut oil modified phenolic resin, phosphogypsum whisker, rice hull-based biomass charcoal, chopped carbon fiber, aramid pulp, chopped basalt fiber, fluororubber, nano titanium oxide, filler, curing agent, plasticizer and antioxidant. The invention strengthens mechanical bearing through directional arrangement of magnetic fields, and cooperatively improves thermal stability, friction and wear performance and corrosion resistance and weather resistance by means of functional components. The prepared composite material has excellent mechanical strength, good thermal stability and stable high-temperature friction performance, realizes the high-value utilization of industrial phosphogypsum solid waste, has simple process and high industrial feasibility, and can be widely applied to the fields of friction materials, building structural parts, automobile parts and the like.

Inventors

  • ZHANG XIANG
  • GUO JIANBING
  • ZHANG KAI
  • WEI LANLAN
  • LI SHENGNAN
  • JIANG TUANHUI

Assignees

  • 贵州省材料产业技术研究院

Dates

Publication Date
20260512
Application Date
20260213

Claims (10)

  1. 1. The phosphogypsum whisker/fiber reinforced composite material is characterized by comprising, by weight, 60-80 parts of cashew nut oil modified phenolic resin, 15-30 parts of phosphogypsum whisker, 2-5 parts of rice hull-based biomass charcoal, 2-6 parts of chopped carbon fiber, 1-4 parts of aramid pulp, 2-5 parts of chopped basalt fiber, 1-4 parts of fluororubber, 0.5-2 parts of nano titanium oxide, 3-8 parts of filler, 4-6 parts of curing agent, 1-3 parts of plasticizer and 0.5-1 part of antioxidant; The preparation method of the phosphogypsum whisker comprises the steps of firstly carrying out acid washing and impurity removal on industrial phosphogypsum, then carrying out hydrothermal crystal form optimization to prepare the phosphogypsum whisker, and finally carrying out ultrasonic modification by a silane coupling agent to obtain the phosphogypsum whisker; The filler is aluminum oxide, calcium carbonate, zinc oxide, kaolin, barium sulfate and graphite.
  2. 2. The phosphogypsum whisker/fiber reinforced composite material according to claim 1, wherein the phosphogypsum whisker, the chopped carbon fiber and the chopped basalt fiber are subjected to graded modification and directional arrangement treatment, and the graded modification steps are as follows: Screening the modified phosphogypsum whiskers to obtain three particle size groups with particle size corresponding to 10-50 mu m, 50-100 mu m and 100-200 mu m; Mixing the phosphogypsum whiskers with three particle size groups with the chopped carbon fibers and the chopped basalt fibers respectively according to a mass ratio of 3:1:1 to obtain three parts of mixture; Secondly, respectively adopting 3% KH560 and 570 and KH792 silane coupling agents to secondarily modify the three parts of the mixture, and compounding the three parts of the mixture according to the mass ratio of 2:3:1 after modification to obtain a fiber mixed material; The directional arrangement treatment is to apply a directional magnetic field of 0.2-0.5T in the forming process of the composite material, so that the mixed fibers of the composite material are arranged along the stress direction.
  3. 3. The phosphogypsum whisker/fiber reinforced composite material according to claim 1, wherein the rice hull-based biomass charcoal is pore-enlarging modified biomass charcoal, and the rice hull-based biomass charcoal enlarging method comprises the following steps: Mixing the rice hull-based biomass charcoal with a potassium hydroxide solution with the mass fraction of 10% according to a solid-to-liquid ratio of 1:15, and stirring for 2 hours at the temperature of 80 ℃ to obtain a mixture; The mixture is activated for 1h under the nitrogen atmosphere at the temperature of 800 ℃, cooled, washed to be neutral and dried to obtain the modified biomass charcoal with the specific surface area of 500-600m 2 /g.
  4. 4. The phosphogypsum whisker/fiber reinforced composite material according to claim 1, wherein the pickling impurity removal method for preparing the phosphogypsum whisker specifically comprises the following steps: Mixing the industrial phosphogypsum with 5% of dilute hydrochloric acid according to a solid-to-liquid ratio of 1:8, stirring for 60min at a temperature of 30 ℃, filtering, washing to neutrality, and drying to obtain phosphogypsum; The hydrothermal crystal form optimization process for preparing phosphogypsum whiskers specifically comprises the following steps: mixing the phosphogypsum after acid washing with water according to a solid-to-liquid ratio of 1:40, pulping, adding a magnesium sulfate crystal form growth promoter with the mass of 3% of the phosphogypsum, carrying out hydrothermal reaction for 4 hours under the conditions of 130 ℃ and 0.3MPa of vacuum degree, filtering and drying reactants, and carrying out ultrasonic modification by using a silane coupling agent to obtain the phosphogypsum whisker with the target size.
  5. 5. The phosphogypsum whisker/fiber reinforced composite material according to claim 1, wherein the phosphogypsum whisker has a length of 10-200 μm and a diameter of 1-50 μm; The cashew nut oil modified phenolic resin is light yellow powder, the fluidity is 25-40 mm, the polymerization time is 40-65 s at 150 ℃, the free phenol content is 2-4%, the hexamethylenetetramine content is 9.0-10.0%, and the granularity is 200 meshes.
  6. 6. The phosphogypsum whisker/fiber reinforced composite material according to claim 1, wherein the chopped carbon fiber has a length of 2.0-6.0 mm, a diameter of 10 μm, a tensile strength of not less than 200ksi, a modulus of 100-135Msi and a carbon content of not less than 99%; The length of the aramid pulp is 2mm, the diameter is 12 mu m, the tensile strength is more than or equal to 3.6GPa, the modulus is 100-150GPa, the length of the chopped basalt fiber is 3-6 mm, and the diameter is 17 mu m; The fluororubber is FKM26, the fluorine content is about 66%, and the fluororubber is used for improving the corrosion resistance of the composite material by cooperation with the raw materials; The nano titanium oxide is rutile type and oily, has an average particle size of about 200nm and is used for improving the weather resistance and the wear resistance of the composite material; the fillers are all of industrial grade and have particle size of 150-1250 meshes.
  7. 7. The preparation method of the phosphogypsum whisker/fiber reinforced composite material is characterized by comprising the following steps: S1, modifying phosphogypsum to obtain phosphogypsum whiskers, and carrying out hierarchical modification and shaping arrangement treatment on the phosphogypsum whiskers, chopped carbon fibers and chopped basalt fibers to obtain a fiber mixed material; s2, carrying out modification treatment on the rice hull-based biomass charcoal, cooling to room temperature after the treatment is finished, putting the modified rice hull-based biomass charcoal and nano titanium oxide into a high-speed mixer, and premixing for 10-15 min at the rotating speed of 800-1000r/min to enable the nano titanium oxide to be uniformly adsorbed in the pore channels of the rice hull-based biomass charcoal, so as to obtain a composite filler for standby; S3, adding cashew nut oil modified phenolic resin and fluororubber into an internal mixer, and premixing for 5-8 min under the conditions of 110-120 ℃ and 50-60r/min rotating speed, so that the fluororubber is completely melted and uniformly dispersed in a matrix of the cashew nut oil modified phenolic resin to obtain a resin premix for standby; S4, sequentially adding the composite filler, the aramid pulp, the filler, the curing agent, the plasticizer and the antioxidant into the resin premix, mixing, adding the fiber mixed material, mixing by an internal mixer, and performing magnetic field assisted compression molding and curing treatment after mixing to obtain the composite material.
  8. 8. The preparation method of the phosphogypsum whisker/fiber reinforced composite material according to claim 7, wherein the magnetic field assisted compression molding in the step S4 is specifically as follows: Placing the mixed materials into a forming die of a magnetic field forming press, starting a magnetic field generating device to apply a directional magnetic field of 0.2-0.5T, wherein the magnetic field direction is consistent with the subsequent actual stress direction of the composite material; and (3) feeding the molding die into a magnetic field molding press, pre-pressing for 5min at the temperature of 150 ℃ and the pressure of 15MPa, discharging air bubbles in the material, heating to 170 ℃, pressurizing to 20MPa, hot-pressing for 30min at the constant temperature and the constant pressure, and hot-pressing to obtain a material primary product.
  9. 9. The method for preparing phosphogypsum whisker/fiber reinforced composite material according to claim 7, wherein the curing treatment in step S4 is specifically: Closing a magnetic field after molding, taking out a molding die and a material primary product, putting the material primary product into an oven, raising the temperature to 120 ℃ at a temperature raising rate of 5-8 ℃ per minute, preserving heat for 2 hours, raising the temperature to 150 ℃ at the same temperature raising rate, and preserving heat for 2 hours; And after the heat preservation is finished, closing the oven, naturally cooling the material primary product to the room temperature along with the oven, avoiding the generation of internal stress due to forced cooling, and obtaining the composite material after the cooling is finished.
  10. 10. The method for preparing phosphogypsum whisker/fiber reinforced composite material according to claim 7, wherein the mixing temperature of the internal mixer is 120-130 ℃, the mixing rotating speed is 60r/min, and the mixing time is 15-20 min.

Description

Phosphogypsum whisker/fiber reinforced composite material and preparation method thereof Technical Field The invention relates to the technical field of composite materials, in particular to an phosphogypsum whisker/fiber reinforced composite material and a preparation method thereof. Background Phosphogypsum whisker (the main component is CaSO 4 -W) is a calcium sulfate whisker prepared by taking industrial byproduct phosphogypsum as a raw material, belongs to a novel environment-friendly functional material, is a fibrous single crystal of ‌ anhydrous or semi-hydrated calcium sulfate, has a unique needle-shaped or fibrous structure, and is one of main ways of phosphogypsum resource utilization when being applied to composite materials. In the prior art, phosphogypsum whisker reinforced materials are treated only by adopting a single modification mode and fibers are randomly distributed, so that phosphogypsum whiskers are easy to agglomerate, the interfacial binding force between the reinforced fibers and a resin matrix is uneven, local stress concentration is easy to occur when the phosphogypsum whisker reinforced materials are stressed, the mechanical properties (tensile strength, bending strength and bending fatigue resistance) of the composite materials are limited to be improved, and meanwhile, comprehensive optimization of corrosion resistance, weather resistance and flame retardance cannot be achieved cooperatively, so that the application requirements of the fields of construction, automobiles, equipment, traffic and the like on high-performance structural members are difficult to meet, and the high-value recycling utilization of industrial phosphogypsum solid wastes is limited. Disclosure of Invention Aiming at the defects of the prior art, the invention provides an phosphogypsum whisker/fiber reinforced composite material and a preparation method thereof, and solves the problems mentioned in the background art. The phosphogypsum whisker/fiber reinforced composite material comprises, by weight, 60-80 parts of cashew nut oil modified phenolic resin, 15-30 parts of phosphogypsum whisker, 2-5 parts of rice hull based biomass charcoal, 2-6 parts of chopped carbon fiber, 1-4 parts of aramid pulp, 2-5 parts of chopped basalt fiber, 1-4 parts of fluororubber, 0.5-2 parts of nano titanium oxide, 3-8 parts of filler, 4-6 parts of curing agent, 1-3 parts of plasticizer and 0.5-1 part of antioxidant; The preparation method of the phosphogypsum whisker comprises the steps of firstly carrying out acid washing and impurity removal on industrial phosphogypsum, then carrying out hydrothermal crystal form optimization to prepare the phosphogypsum whisker, and finally carrying out ultrasonic modification by a silane coupling agent to obtain the phosphogypsum whisker; The filler is aluminum oxide, calcium carbonate, zinc oxide, kaolin, barium sulfate and graphite. Preferably, the phosphogypsum whisker, the chopped carbon fiber and the chopped basalt fiber are subjected to grading modification and directional arrangement treatment, and the grading modification steps are as follows: Screening the modified phosphogypsum whiskers to obtain three particle size groups with particle size corresponding to 10-50 mu m, 50-100 mu m and 100-200 mu m; Mixing the phosphogypsum whiskers with three particle size groups with the chopped carbon fibers and the chopped basalt fibers respectively according to a mass ratio of 3:1:1 to obtain three parts of mixture; Secondly, respectively adopting 3% KH560 and 570 and KH792 silane coupling agents to secondarily modify the three parts of the mixture, and compounding the three parts of the mixture according to the mass ratio of 2:3:1 after modification to obtain a fiber mixed material; The directional arrangement treatment is to apply a directional magnetic field of 0.2-0.5T in the forming process of the composite material, so that the mixed fibers of the composite material are arranged along the stress direction. Preferably, the rice hull-based biomass charcoal is pore canal reaming modified biomass charcoal, and the rice hull-based biomass charcoal reaming method comprises the following steps: Mixing the rice hull-based biomass charcoal with a potassium hydroxide solution with the mass fraction of 10% according to a solid-to-liquid ratio of 1:15, and stirring for 2 hours at the temperature of 80 ℃ to obtain a mixture; The mixture is activated for 1h under the nitrogen atmosphere at the temperature of 800 ℃, cooled, washed to be neutral and dried to obtain the modified biomass charcoal with the specific surface area of 500-600m 2/g. Preferably, the acid washing impurity removal method for preparing phosphogypsum whiskers specifically comprises the following steps: Mixing the industrial phosphogypsum with 5% of dilute hydrochloric acid according to a solid-to-liquid ratio of 1:8, stirring for 60min at a temperature of 30 ℃, filtering, washing to neutrality, and drying to obtain phosphogypsum