PHOTO: New development - the use of nanostructured materials in flame retardant systems includes special intercalated graphite-based additives. When these graphite flakes are exposed to high heat they expand in a worm-like manner as seen here in the electron microscope image, increasing in volume more than one hundred times

SOUTH African custom plastics additive compounder, Xyris Technology, understands the importance of research and development in the ever-changing chemicals industry and plays an active role in supporting research activities in South Africa.

The Bashewa-based company has worked with the Institute of Applied Materials (IAM) at the University of Pretoria to supply the masterbatches that were used in the manufacture of an insecticidal wall lining developed by the University to counter the spread of malaria.

This novel product combines the advantages of mosquito bed nets with the indoor residual spraying of walls. Field trials started two years ago and the product is performing very well. Xyris Technology is confident that this kind of product will eventually make it possible to phase out DDT, the controversial chemical currently used to ward off mosquitoes.

Xyris Technology has also developed specialised flame retardant masterbatches and compounds. These include products for deep underground mining applications that comply with the unique specifications of the South African Chamber of Mines.

Systems are available to flame retard woven textiles, extruded items, injection moulded and roto moulded products. Proprietary UV stable masterbatches were supplied by Xyris Technology to flame retard stadium chairs manufactured locally for football stadia used during the 2010 Soccer World Cup hosted by South Africa.

While many of these products are bromine-based, an exciting new development is the use of nanostructured materials in flame retardant systems. This includes special intercalated graphite-based additives. When such graphite flakes are exposed to high heat they expand in a worm-like manner increasing in volume more than one hundred times. (See the electron microscope image.)

When products containing this additive are exposed to fire, a foamed insulating char layer is formed that prevents further degradation of the polymer substrate. Current expandable graphite grades are very effective as intumescent flame retardants in polyethylene, PVC and also in polyurethane foams. Xyris Technology foresees significant future growth in this type of halogen-free system.

Xyris Technology also produces the well-known purging compounds, Extru-Clean and Eco Purge under license to the CSIR, which are also exported worldwide. The corrosion inhibitor range includes proprietary products as well as formulations licensed from the CSIR and supplied under contract to a major South African player in this field. The main applications are in protective films that are used to package steel products that are exported via ocean shipping.

www.xyris.co.za