METHOD OF MANUFACTURING OF A PREPREG AND A DEVICE FOR ITS REALIZATION Russian patent published in 2004 - IPC

FIELD: chemical industry; manufacturing of prepregs.

SUBSTANCE: the invention is pertinent to chemical industry and to the methods of production of the prepregs - semi-finished items representing fibrous filler impregnated with a binding agent in a fixed weight ratio and ay be used in many industries at manufacturing structures out of reinforced composite materials, for example, vertical web members, rods, supports, pipes, containers and balloon tiers, with a filler in the form of the glass, organic and carbon filaments reprocessed using a "dry" winding technique. The method provides for coiling of the filler on a mandrel in spools, degassing and filling in with the binding agent. The filler coiling on a mandrel is made with volume of a free space equal to the required ratio of the binding agent and not less than 0.2 from the total volume of the formed spool. The degassing is conducted in a chamber for no less than 4 hours at a residual pressure not exceeding 10 mmHg. Filling in of the inter-fiber and inter-filament spaces of the spools with the binding agent is made by dipping of the spools with the filler under the same conditions of vacuum in the binding agent medium. When the volume of the binding agent above the spools exceeds the volume of inter-fiber and inter-filament spaces in the spool the chamber pressure is lifted up to the value no less than atmospheric pressure and keep the spool in the volume of the binding agent for no less than 4 hours. Then they wait till surplus of the binding agent flows down. The device for realization of the method contains: a vacuum chamber with a vacuum pump, a vacuum gate and a manometer; a container with the binding agent and spools with the filler. In the container with the binding agent there is a loading perforated platform with a central rod perpendicular to a plane of the platform and linked with a mechanism for pushing the platform down. The spools with the filler are installed on the loading perforated platform interleaving with the intermediate perforated demountable platforms. Between mandrels of the spools and the central rod there are load disks. The invention ensures a raise of quality of wettability of filaments and impregnation of a filler in a prepreg, reduction of inter-fiber and inter-filament porosity prior to beginning of an impregnation process, that allows to improve tightness of the items produced out of prepregs.

EFFECT: the invention ensures a raise of quality of wettability of filaments and impregnation of a filler in a prepreg, reduction of inter-fiber and inter-filament porosity and improvement of tightness of the items produced out of prepregs.

2 cl, 3 dwg