Seals Eastern, Inc. CHEMICAL RESISTANT seals, gaskets, and o-rings for use in chemical reagents including organic and inorganic acids, alkalines, ketones, esters, hydrocarbons, alcohols, fuels, gases, steam, and hot water. 134 PEARL STREET RED BANK, NJ 07701-0520 USA TEL: 732 747 9200  FAX: 732 747 3647

When searching for a chemical resistant o-ring, gasket, or seal, the most successful elastomers will be in the class of fluorocarbon rubbers. Several characteristics of  fluorocarbon rubber tend to impart the characteristics necessary for chemical resistance, specifically, the ratio of fluorine to hydrogen, the inherent strength of the carbon-fluorine bond, the absence of carbon bond unsaturation, and the steric hindrance associated with fluorinated structures. As a general rule, the higher the fluorine content, the broader the chemical resistance. However, there are exceptions to this rule that can be attributable to the solubility parameter of a given reagent and the elastomer designated to seal the reagent. Consideration must also be given to the curative employed within the fluorocarbon rubber. The second rule of thumb is that the higher the fluorine content, the more expensive the polymer will be. But again, exceptions exist. For instance, a Type 2 FKM (such as Viton ® B) possesses a higher Fluorine content than an Aflas ® FEPM, yet the FKM costs less. Generally speaking, FKMs will be the least expensive fluorocarbon elastomer, followed by FEPM, with the most expensive being FFKM.  Good background information on Fluorocarbon Elastomers can be found in our Technical Papers Online page. For information on base resistance you may want to visit our statement about BREs. ASTM  D1418 Compound No. Shore-A Hardness Description FKM       Type 1 5717 70 Formulated Fluorel ®. General service. Type 1 7145 80 Formulated Fluorel ®. Specially for hydrocarbons. Type 1 7130 90 Formulated Fluorel ®. Specially for hydrocarbons. Type 1 7148 95 Formulated Fluorel ®. Specially for hydrocarbons; ED resistant Type 2 5722 60 Formulated Viton ®. General chemical service. Type 2 5723 75 Formulated Viton ®. General chemical service. Type 2 5724 85 Formulated Viton ®. General chemical service. Type 2 5725 95 Formulated Viton ®. General chemical service. FEPM         7265 80 Formulated Viton ® ETP formulation. Broad chemical resistance. FFKM-type performance.   7182D 80 Formulated AFLAS ®. Excellent resistance to steam, acids, bases and other chemical families. Excellent mechanical properties.   7182X 80 Formulated AFLAS ®. Excellent resistance to steam, acids, bases and other chemical families. Ultra-low compression set.   7182B 90 Formulated AFLAS ®. Excellent resistance to steam, acids, bases and other chemical families. Excellent mechanical properties. FFKM         9291 70 Broad chemical resistance for less cost.   9295 75 Ultra-high temperature service.   9294 80 High temperature service; Broad chemical resistance. SEALS EASTERN MOLDING SUCCESS FOR 50 YEARS. ISO 9001:2008 CERTIFIED - BVQi (NA), Inc.

FastDash ™ is a trademark of Seals Eastern, Inc.; OringOnline ® is a registered trademark of Seals Eastern, Inc.; 7182 ™ is a trademark of Seals Eastern, Inc.; AFLAS ® is a registered trademark of Asahi Glass Co., Ltd.; Viton ® is a registered trademark of Dupont Performance Elastomers, LLC.; Fluorel ® is a registered trademark of 3M.