Composite recycle technology proven

Toyota is looking at the possibility of using recyclable composite plastics on its car air intake manifolds to reduce the environmental footprint. Dean Palmer reports "Our vision includes improving the vehicle recovery rate to 95 per cent and developing new technologies that increase the use of plastic from recycled materials or renewable resources to 20 per cent by 2015," explained Yasushi Miyamoto, general manager organic material department at car manufacturing giant Toyota. He continued: "We plan to continue to develop this new technology so it can be applied economically to our vehicle recycling initiatives. DuPont's Composite Recycle Technology is very important in helping us achieve this vision." Toyota made the announcement at the recent International Automotive Recycling Conference in Geneva, Switzerland. The company said it had confirmed the feasibility of DuPont's recycling technology as a means of reclaiming and reusing nylon 6 from its automotive air intake manifolds and reducing the environmental footprint, but that there were still concerns surrounding the economic feasibility of such a move. William Hsu, VP and chief technical officer at DuPont Performance Materials explained further: "DuPont's recycling technology delivers polymer that is, from a technical view point, equivalent to virgin, while reducing the environmental footprint. The remaining challenge is in the economic factor - feedstock shortages and undeveloped collection processes suggest the economic case is still not optimal." In the study, DuPont's composite recycling technology was analysed along the three dimensions of sustainability, including end-use component testing; life cycle analysis to understand total environmental footprint; and economic scenarios to help focus future development activities. DuPont Composite Recycle Technology is a closed loop nylon recycling process which converts parts made of glass- or mineral-filled nylon 6 or nylon 66 into resin that is essentially equivalent to the virgin material. The process dissolves used polyamide then filters away contaminants and fillers. The molecular weight of the recovered polyamide is increased to whatever level is desired for the final application. Toyota and DuPont tested two identical air intake manifolds, one made from compounded virgin nylon 6, the other from compounded resin containing 100% recycled nylon 6. The results of end-use testing for leaks, burst and breaking strength showed that parts made of recycled content were within specification. And life cycle analysis of energy usage and CO2 emissions also indicated that the environmental footprint of DuPont's technology was lower than virgin processes. The economic comparison factored all steps associated with recycling: collection; disassembly; feedstock separation; and the recycling process. Explained Hsu: "Part of the challenge is that Japan has only recently adopted nylon 6 for air intake manifolds, so components in sufficient quantities will not be available until 2010. "Using nylon 6 from wheel covers, fans and shrouds and beauty covers is worthy of investigation," he added, "but different regions of the world are at different stages of using nylon 6 and of collecting landfill parts. This aspect of the process remains a significant variable." He said the key step was to "improve the cost of the overall process" by companies in the supply chain collaborating together to help clarify the development. Ultimately, he explained, "companies create a sustainable solution, technically, environmentally and economically."