Bayer MaterialScience (BMS, Leverkusen / Germany; www.bayerbms.com) has developed a flame-retardant PC/ABS blend for use in applications in extremely warm, humid environments. “Bayblend” FR 3008 HR (hydrolysis resistant) was developed in cooperation with the dishwasher product area of BSH Bosch and Siemens and is used to protect electronic parts in the latest generation of its dishwashers. In aging tests, the material remained resistant to hydrolytic molecular degradation after being stored in an 80 °C water bath in constant contact with steam for 60 days. The yield stress of the blend showed virtually no change throughout the storage period and the material remained resistant to chemicals, BMS said.

In order to recreate the stress on the blend during a washing cycle as accurately as possible, in addition to being subjected to pure steam, they were also exposed to common additives such as detergents and rinse aids and to simulated fatty deposits. To ensure reliable operation in the long term, the material had to undergo numerous other tests on its properties, including mechanical thermal aging, dimensional stability, chemical resistance and moisture absorption, long-term heat resistance, glow wire tests and assessments of optical quality characteristics based on colour stability.