| 摘要 |
The invention relates to processes for the production of a composite component via multicomponent injection molding, where the composite component comprises a main body composed of a thermoplastic A) and an external layer composed of a foamed thermoplastic B), where the main body is produced in a first process step a) via injection molding of the thermoplastic A) and subsequent hardening of the same in an injection mold, and an external layer is injected on to the main body in a second process step b) which follows directly, via injection molding of a mixture comprising the thermoplastic B) and comprising a chemical blowing agent, and the mixture is subsequently hardened in the same injection mold, with somewhat extended cavity, and the external layer injected on to the main body is foamed in a further process step d) via introduction of heat, and the composite component is solidified via cooling in a final process step e), where an essential feature of the invention is that it comprises using, as thermoplastic B) in the mixture used in process step b), at least one polyamide whose modulus of elasticity derived from the tensile test (tensile modulus) Et is from 1 MPa to 250 MPa (determined to DIN EN ISO 527 of April 1996) in the entire temperature range from 70° C. to 180° C., and using, as chemical blowing agent in the mixture used in process step b), one or more substances present in non-polymerized form. The invention further relates to composite components and to reinforced load-bearing elements, where these can be produced by said processes, and also to mixtures, and to the use of said mixtures for the production of composite components. |
