Silicone Engineering, a silicone rubber producer based in Blackburn, has completed a research exercise to assess the heat resistance of silicone rubber compared to Ethylene Propylene Diene Monomer (EPDM).
Its research, comparing silicone rubber to EPDM, has shown silicone rubber has superior qualities for temperature resistance. Silicone rubber degrades at 230°C, though EPDM will suffer adverse effects after 130°C.
Some special high-temperature silicone rubbers can resist temperatures up to 270°C, and silicone will also retain flexibility in temperatures down to -60°C.
Silicone blocks
Kadian Jenkins, Marketing Executive at Silicone Engineering, said: “When subjected to constant heats of 100°C through to 175°C, EPDM shows a massive reduction in size and fundamental deterioration in strength, compared to its silicone counterpart. Therefore, silicone is ideal for industries where retention of initial shape and mechanical strength are desired under heavy thermal stress or sub-zero temperatures.
“We obtained EPDM samples and tested them at various high temperatures to see how they performed. We were very surprised to find that all the EPDM samples dramatically reduced in size compared with our equivalent silicone grade. In addition, we found very different results from every sample that was tested, leading us to think consistency within the EPDM market is quite erratic.
“The results of the tests were quite worrying especially from the user’s perspective showing that the rapid reduction in size and deterioration of mechanical properties could easily lead to complete failure of the EPDM in the application.”
Silicone Engineering’s research can be viewed in full here.