Forming mold and preparation method of composite material anti-pollution barrel

The invention provides a forming die and a preparation method of a composite anti-pollution barrel. Comprising a mandrel, a cover plate and an air tap. The core mold and the cover plate are made of aluminum alloy; vent holes are formed in two ends of the mandrel; the cover plate and the core mold are positioned through the positioning step and are locked through a screw to form a male mold; the air tap is connected to the cover plate; the vacuum pipeline is connected with the air nozzle to vacuumize the male mold inner cavity, so that the male mold inner cavity forms negative pressure relative to the external environment; laying the cut polyimide single-sided aluminized film on the core mold, and adsorbing the cut polyimide single-sided aluminized film on the core mold through negative pressure; laying the cut prepreg on a polyimide single-sided aluminum laminated film; carrying out overall bag making and vacuumizing on the male mold, and pressurizing and curing through an autoclave; and after curing, the cov