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Structural Reaction Injection Molding (SRIM) is generally regarded as a thoroughly developed technology and is currently utilized in many automotive applications; most prominently door panels but also other applications, for example package trays and headliners. The traditional production process involves the placement of a glass fiber mat into a mold prior to injection of a suitable liquid resin system. Upon removal of the part, the glass mat is thoroughly encapsulated by the resin system forming a structural composite material. In the new Long Fiber Injection (LFI) process, the glass fibers are injected along with the resin mixture onto the production mold. This new process demonstrates a new approach to high productivity, low cost manufacture of LD-SRIM composites.

Glass mat reinforced structural polyurethane foam or low density structural reaction injection molding (LD-SRIM) has found a niche in the manufacture of high quality, light weight, automotive, interior trim substrates. Current trends in the automotive industry indicate the need for cost reductions without sacrificing quality. A high productivity LD-SRIM system has been developed which meets this need. This cost reduction is achieved by the incorporation of an internal mold release agent and a 25 % decrease in demold time compared to current LD-SRIM technology. These technological advancements give the trim component manufacturer an increase in productivity by eliminating the time and labor required to apply external mold release and a shorter demold time. These advancements also provide for a significant reduction in the volatile organic compounds and cost associated with external mold release agents.

Cream foam is a polyurethane technology designed for molding foam articles such as automotive headrests or armrests directly into their decorative coverstocks. This process allows for the single step molding of covered foam articles eliminating the secondary step of attaching the cover needed in conventional operations. The advantage cream foam offers over conventional molded foam is that penetration of the stitched seams and foam backing of the coverstock is avoided or controlled. Cream foam technology has improved with the development of a MDI-based polyurethane system that reduces penetration of the foam and fabric bilaminate coverstocks by 25% and the molded foam density by 15%. These improvements result in a cost reduction in the manufacturing of arm or head rests.

A physical recycling scheme for in-house Low Density Structural RIM (LD-SRIM) process scrap has been developed by ICI which uses size-reduced LD-SRIM as a filler for the production of new panels with recycled content. Two pulverization methods, hammer mill and pellet mill, were tested and SEM analysis and particle size distributions of the size-reduced LD-SRIM are presented to show the effectiveness of the pulverization process. The pulverized LD-SRIM scrap was added to a commercial polyol blend. Parts were molded and physical properties measured varying filler loading, particle sizes, filler type, and part density. The addition of recycle filler had no significant detrimental effect on the urethane system with respect to material reactivities, flow, and part physical properties.

Management of manufacturing scrap and post-consumer scrap from automobiles will increasingly influence both the acceptance of plastics and choice of plastics in the automotive industry. Polyurea elastomers made by reaction injection molding (RIM) offer many processing, property and cost advantages desired by the automotive industry but their crosslinked nature has generally implied that the scrap cannot be recycled by a widely used recycling method, thermal processing. Recently introduced ICI Polyurethanes imine-polyurea materials for automotive exterior applications can be thermally processed using extruders into sheets, profiles, tubes, moldings etc. The extruded materials have good mechanical integrity and many end-use applications are possible.

Weight reduction with maintained part performance is a continuing trend throughout the automotive industry. Acoustical insulation parts (carpet underlay and dash insulators) are no exception. Several years ago, ICI Polyurethanes led the industry in establishing a molded density standard of 48 kg/m3. Although this is the current production standard, the technology drive is toward even lower weights. Recent technological demonstrations show that molded densities of 35-38 kg/m3 are achievable. In addition to removing weight, acoustical performance can be maintained with no deficiencies in physical characteristics.

In response to the impending curtailment of the availability and use of chlorofluorocarbons (CFC's) and hydro-chlorofluorocarbons (HFC's), a water blown integral skin foam (ISF) system has been developed. In meeting the environmental challenge, automotive steering wheels were chosen as the targeted market. A discussion of the developmental strategies and efforts is presented along with a comparison of the new system to current technology. Also shown is the ability of the system to comply with automotive performance requirements and to process according to current production standards. After examining the favorable economic implications of the new system, the paper concludes that this water blown ISF system is a viable, practical and environmentally acceptable alternative to current CFC technology.