METHOD FOR MANUFACTURING CARBON FIBER BASED ON WOVEN CARBON FILLER AND THERMOPLASTIC BINDER Russian patent published in 2022 - IPC C08J5/10 C04B35/80 

FIELD: carbon fiber production.

SUBSTANCE: invention relates to the technology of manufacturing carbon fiber, which is intended for use in the design of elements and assemblies of the nacelle. A method is proposed, in which: prepreg is formed by drying a carbon filler, applying a binder to it by electrostatic spraying and impregnating it with a binder, prepreg workpieces are formed, and a package is assembled from them, the package is placed between preheated mold plates, and carbon fiber is formed by stepwise pressing the package in three stages at a temperature exceeding the melting point of the binder, and the resulting carbon fiber is cooled under pressure. A woven carbon filler is used as a carbon filler, then, the woven carbon filler is cut with subsequent drying. Then, alternately, a powdered polyester-esterketone binder with an average particle size of 90-150 mcm is applied to front and rear sides of the mentioned carbon filler, while on front and rear sides of the mentioned carbon filler, the binder content in prepreg is 42±3%, and the mentioned binder is melted at a temperature of 390-410°C for 5-10 minutes. At the same time, prepreg workpieces are placed in a thermal cabinet on perforated shelves, on which an anti-adhesive layer is laid in the form of polyimide film with a thickness of 100-150 mcm, which is removed after cooling the prepreg workpiece, and prepreg sheets are cut, a package is assembled from them and placed between mold plates preheated to a temperature 30-50°C below the melting point of the binder. Next, the mentioned package is heated to a temperature 50-70°C above the melting point of the binder at specific pressure of 0.1-0.5 MPa to remove air, then, it is pressed at a temperature exceeding the melting point of the binder by 50-70°C in three stages: the first stage is carried out at specific pressure of 0.5-1.0 MPa, the second stage – at specific pressure of 1.1-2.0 MPa, and the third stage – at specific pressure of 2.1-2.5 MPa. The duration of each stage is 10-30 minutes, after pressing the package, press plates are cooled at specific pressure of 2.1-2.5 MPa to a temperature not higher than the glass transition temperature of the binder.

EFFECT: manufacture of carbon fiber having high physical and mechanical properties, increase in the degree of impregnation, decrease in the porosity of carbon fiber.

1 cl, 2 tbl, 6 ex