Newly designed screw elements facilitate processing of synthetic biodegradable material

29-Aug-07

An innovative process facilitates manufacture of packaging films made of biodegradable materials for consumer industries, using starch. Newly designed screw elements in the compounder, enables for the first time, this processing of synthetic biodegradable material that can be specifically produced with variable starch and moisture content levels to suit injection moulding or blow moulding processes. This process has been developed by Reimelt Henschel MischSysteme GmbH in co-operation with German research institutes. To develop this special product, the co-rotating Reimelt Henschel twin-screw extruder has been optimised in several aspects. To achieve the properties required it is necessary to compound the material at extremely low shear rates under highly accurate temperature control and using a new combined vacuum/atmospheric degassing system. Start-up of the pilot plant in Germany with a capacity of 400 kg/hr is scheduled for the end of 2007. Mass production will be started in Thailand in spring 2008. Current environmental laws in Australia and New Zealand require that packaging films for consumer industries be made of biodegradable materials. A corresponding law for the application of biodegradable plastics for packaging film is expected to be implemented in 2010 in France. Further impact all over Europe is to be expected in the near future.