Full definition
Fluoroelastomer — a family of high-performance synthetic rubbers containing 64-70% fluorine by weight, providing exceptional resistance to mineral oils, fuels, hydraulic fluids, aromatic solvents, concentrated acids, and many aggressive chemicals that destroy conventional elastomers. Temperature range: -20 to +200°C continuous (specialty low-temp grades to -40°C). Properties: hardness 60-90 Shore A, tensile 10-17 MPa, very low compression set at high temperature, negligible gas permeability, inherent flame resistance. ASTM D2000 classification: HK. Types by fluorine content: Type 1 (66% F, standard — Viton A), Type 2 (68% F, better fuel resistance — Viton B), Type 3 (highest F, best chemical resistance — Viton F), Type 4 (TFE/propylene, base-resistant — Viton Extreme/Aflas). Limitations: poor resistance to low-molecular-weight esters, ketones, amines, hot water, and steam; poor low-temperature flexibility (standard); high cost ($20-80/kg). Applications: O-rings and seals for oil/gas, chemical processing, automotive fuel systems, aerospace, semiconductor, and pharmaceutical. Brands: Viton (Chemours), Dai-el (Daikin), Tecnoflon (Solvay), Dyneon (3M).