Connecting fiber-reinforced material to an injection-moulded material
A process for the bonding of a fiber-reinforced material to an injection-molding material and an article produced by the process. The process improves the bond between a fiber-reinforced starting material and a material applied by injection. A further plastics material is inserted under pressure into a fiber-reinforced plastics material. This results in interlock bonding between the further plastics material and the fibers of the fiber-reinforced plastics material. This type of bonding is substantially more stable than known bonding.
1. A process for bonding a fiber-reinforced plastics material to a further plastics material, said process comprising:
(a) introducing the fiber-reinforced plastics material into an injection mold, wherein the injection mold has, behind the fiber-reinforced plastics material introduced, at least one depression, wherein the fiber-reinforced plastics material has first and second opposing sides differing in distance from the at least one depression, and wherein the first of said opposing sides is a farther distance from said at least one depression than said second of said opposing sides, and
(b) bonding the fiber-reinforced plastics material to the further plastics material by inserting the further plastics material under pressure into the fiber-reinforced plastics material from said first side, and continuing between fibers of said fiber-reinforced plastics material so that the fiber-reinforced plastics material is thereby displaced into the at least one depression, and the further plastics material is eventually pressed outward of the fiber-reinforced plastics material at said second side.
2. The process according to claim 1 , which comprises inserting the further plastics material under a pressure of from 600 to 1000 bar into the fiber-reinforced plastics material from said first side.
3. The process as claimed in claim 1 , in which the further plastic is inserted under pressure in the form of points or lines into the fiber-reinforced plastics material.
4. The process as claimed in claim 1 , in which the fiber-reinforced plastics material is softened or plasticized prior to the inserting.
5. The process as claimed in claim 1 , in which the fiber-reinforced plastics material is thermoplastic, and the fiber-reinforced plastics material is heated, prior to the inserting, to a temperature which is at most 20° C. above the melting point of the thermoplastic.
6. The process as claimed in claim 1 , which further comprises preheating fiber-reinforced, thermoplastic material to a temperature which is from 20 to 40° C. above the melting point of the thermoplastic material.
7. The process as claimed in claim 1 , in which the fiber-reinforced plastics material, the further plastics material or both the fiber-reinforced plastics material and the further plastics material comprises polyamide 6,6, polyamide 6, polybutylene terephthalate, polypropylene, polyethylene terephthalate, polyamide 12, polyphenylene sulfide, thermoplastic polyurethane and/or polyamide 4,6, or a mixture thereof.
8. The process as claimed in claim 1 , in which the fiber-reinforced plastics material, the further plastics material or both the fiber-reinforced plastics material and the further plastics material comprises polystyrene, acrylonitrile-butadiene-styrene, and/or polycarbonate, or a mixture thereof.