| 摘要 |
Resin impregnation of fiber bundles for use in making a composite material is described. The impregnated fiber bundles are suitable for use as a prepreg tape or for inline use in extrusion, pultrusion and filament winding operations. The improvements of the disclosed method and impregnation head enable high fiber take-off speeds without excessive damage or fraying of the fiber bundles. Encapsulated air or voids in the impregnated product are consistently less than 1% by volume of the impregnated product and decrease with increased take-off speed. These improvements are achieved by passing the fiber bundles through a multi-chambered impregnation head in which the resin is injected into a downstream chamber. The cross sectional area of the fiber bundles, the velocity of the fibers bundles, the size of the openings to the chamber, the viscosity of the resin and the pressure at which the resin is pumped into the downstream chamber all control the pressure within the downstream chamber. The pressure is adjusted so that the resin flows upstream against the movement of the fiber bundles and sets up a wall of resin in the upstream chamber. The wall of resin minimizes the air that is encapsulated with the resin and prevents air from entering the downstream chamber. The pressures and counter flow of resin within the impregnation head drives encapsulated air out of the resin.
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