Polyurea RIM in Exterior Body Panel Applications 880353
Commercialized use of the reaction injection molding (RIM) process first involved polyurethane elastomers. Improvements to this RIM elastomer system were soon made by the use of a new aromatic-amine chain extender, diethyltoluenediamine (DETDA). New insights on the commercial usefulness of RIM elastomers were provided by these new systems classified as polyurethane/urea RIM elastomers. Recently, a further refined system has begun to make strong headway in the RIM elastomer market. Amine-terminated polyether resins along with the amine chain extender are incorporated into these systems which are referred to as polyurea RIM elastomer.
Polyurea RIM elastomer systems, which require no catalyst, are extremely fast and capable of high productivity. Incorporation of internal mold release agents allow for fast and easy release of parts from molds without external spraying of a release agent. Specific end use requirements can also be met by redesigning the polyurea RIM system. Speed and physical properties of the polyurea RIM systems allow for creative designing in automotive applications. Polyurea RIM elastomers are making significant contributions in automotive fascia material.
To further improve styling uniqueness in automobiles, polyurea RIM elastomers can be used to produce exterior body panels. A wide processing latitude, superior properties and cost advantage of the system make polyurea RIM a good candidate over polyurethane/urea and injection molded thermoplastics. Polyurea RIM elastomers are extremely tough and are not prone to corrosion as are the conventional stamped steel body panels. In this paper, recent advances in polyurea RIM elastomer technology as it relates to exterior body parts will be discussed.