The material combining polylactide acid with petroleum-based plastic is stiffer than PP

Automotive company Mazda is involved a project producing a bioplastic alternative to polyproylene for car interiors. The new bioplastic made of 88% polylactide acid (PLA) and 12% petroleum-based plastic has been developed in a regional revitalisation research programme in the Hiroshima area, promoted by the Japanese Ministry of Economy, Trade and Industry. The project was started in 2004 by a consortium consisting of two universities, seven companies and two research institutes.

According to Mazda, one of the project participants, the new bioplastic has improved surface quality and has not only three times the impact strength and 25% higher heat resistance than conventional bioplastics, but is stiffer than PP. Mazda believes that the new stiff bioplastic can be used to substitute PP with thinner part designs using less materials and moulded in thinner moulds than is presently the case with PP. There is the added advantaged of lower carbon dioxide emissions involved in production of the material.

The key to the development is use of a new nucleating agent for crystallisation and a compatibilising compound developed by Nishikawa Rubber and Kinki University. Mazda will show vehicle interior parts made with the new bioplastic on its stand at the Automotive Engineering Exposition, during the Japan Society of Automotive Engineering Annual Congress in Yokohama between 24-26 May 2006.