Currently, petroleum-derived plastics are used in various parts of automobiles. New materials are being sought that eliminate petroleum-resource dependence, cut CO2 emissions and enable fuel economy to be improved through decreased car bodyweight. The bioplastics presently used in household electronic products, however, lack the strength (impact resistance) and heat resistance required for automotive applications.
In collaboration with industry-academia- government,*1 Mazda has developed the world's first bioplastic that can successfully be employed in car production. This material boasts sufficient surface quality, to facilitate use as interior trim and the strength and heat resistance required for exterior automotive applications. The improvements have been achieved through additives to conventional bioplastics, increasing strength (impact resistance) three-fold and raising heat resistance by 25%. Furthermore, while manufacturing methods of existing bioplastics have been restricted to press molding because of the materials' properties, the newly developed bioplastic can be shaped using injection molding equipment that is commonly used in automotive parts production. This expands the range of parts that the bioplastic can be used for.
*1 Hiroshima University, Nishikawa Rubber Co. Ltd., Western Hiroshima Prefecture Industrial Research Institute, G.P. Daikyo Corporation, the Japan Steel Works, Ltd., Kinki University School of Engineering, Nishikawa Kasei Co. Ltd., National Research Institute of Brewing, Yasuhara Chemical Co. Ltd. and MANAC Inc., and Mazda Motor Corporation (two universities, seven companies and two research institutes).
Bioplastics are carbon-neutral*2 materials derived from plants. They also reduce the consumption of fossil fuels, thus producing less CO2. Moreover, the production process involves the fermentation of starches and sugars contained in plants, so the energy used during production is approximately 30% lower than for a typical plastic, such as polypropylene. In addition, the bioplastic's high rigidity means thinner parts can be molded, which leads directly to savings in the amount of raw plastic needed.
*2 The CO2 discharged during decomposition and combustion of bioplastics is offset by the CO2 that the plants, which are used to produce the plastic, absorb through photosynthesis. Carbon-neutral is a characteristic of materials that do not increase or decrease the amount of CO2 in the atmosphere.
This research was started in 2004, In collaboration with industry-academia- government. It was supported by the Ministry of Economy, Trade and Industry's "Consortium R&D Projects for Regional Revitalization" program. This program aims to revitalize local economy through the creation of new industries and enterprises by joint research projects.
The Hiroshima area is home to world-acclaimed technologies in the field of automotive plastic module parts, led by Mazda and G.P. Daikyo Corporation. In addition, the region's history of brewing has generated a wealth of fermentation technology (biotechnology) expertise. One core group made up of Hiroshima University, Nishikawa Rubber Co., Ltd., and the Western Hiroshima Prefecture Industrial Research Institute greatly advanced knowledge on biodegradable resins through its work on microbiological decomposition. Integrating regional technologies in this way was the springboard that led to the research achievements.
Mazda will continue to commit to bioplastics research and development in concert with the local region, in order to continue developing products over the next few years.