Abstract: The elastomer compatibility of rubber seed oil biodiesel was studied involving eight kinds of elastomers, pure rubber seed oil biodiesel (BD100), 0# diesel fuel, blended rubber seed oil biodiesel (BD20) and nitrile rubbers with various rubber contents. Results showed that when eight kinds of elastomers were soaked in BD100 for a long term, the physical properties of elastomers, such as mass, volume and hardness, were changed and the changes from more to less were in the order of nature rubber＞epdm rubber＞chloroprene rubber＞polyacrylate rubber＞nitrile rubber＞hydrogenated nitrile rubber＞fluoro silicone rubber＞fluorine rubber. Test results of soaking elastomers in 0# diesel fuel, BD20 and BD100 showed that the changes in physical properties of elastomers decreased with the decrease of biodiesel content in fuels. Tests of fuels with nitrile rubbers having various rubber contents showed that the changes of the physical properties of nitrile rubbers varied with the various of rubber content in nitrile rubber, thus the changes of elastomer properties could be altered by adjusting the rubber content in elastomers. However, test results of soaking sealing O-rings from conventional vehicle in BD20 for a long term showed that their compatibility was excellent.

Key words: rubber seed oil biodiesel, elastomer compatibility, diesel fuel, volume, mass, hardness, change