Silicone vs SBR

DATE: 1st-August-2019
Jehbco Silicones is an industry leader, manufacturing high quality silicone extrusions in Australia. Whilst silicone and Styrene Butadiene (SBR) share some similarities in their characteristics and chemical resistance levels, their physical properties vary, which depending on the conditions of application, a justified material selection can be made. 

SBR Silicone
-45° to 100° C -50° to 230° C
Great compression set Excellent compression set
Fair weather resistance Excellent weather resistance
Approx. tensile strength 18 MPa Approx. tensile strength 5 MPa
Excellent abrasion resistance  Poor abrasion resistance
Not compatible with: alphatic hydrocarbon solvents, aromatic hydrocarbon solvents, petroleum products  Not compatible with: hydrocarbon fuels, alkalis and acids, steam over 121 °C, trichloroethylene, aromatic hydrocarbons.
Compatible with: acids, alcohols, oxygenated solvents, oils, alkali, hot and cold water, salt water Compatible with: oils, brake fluids, hot and cold water, salt water, high molecular weight chlorinated hydrocarbons, fire resistant hydraulic fluid, ozone.

Silicone and SBR can both withstand temperatures as low as approximately -40° C, making them both considerable for low temperature applications. However, silicone rubber offers a significantly higher heat resistance making it an ideal material for high temperature applications. 

Very similar to natural rubber, SBR has an excellent abrasion resistance which make an ideal material choice for dynamical applications involving a large amount of physical demand. This is not the case with silicone, which with its low abrasion resistance is much better suited for high-temperature static applications. The tensile strength of SBR is much higher at 18 MPa which also make it an ideal candidate for applications with high dynamical loading and force. 

Both materials exhibit the same degree of compression set allowing both materials being acceptable for applications that demand high durability. 

In general, silicone is an ideal material for static and high-temperature applications whereas SBR is a common elastomer for applications requiring a high resistance to dynamical load and friction. The ideal material for your application highly depends on your requirements. To help guide you in choosing the right material for your application, contact us on our website www.jehbco.com.au.