(PER)FLUOROELASTOMERIC COMPOSITIONS

摘要

A (per)fluoroelastomeric composition curable by peroxidic way comprising for 100 phr of (per)fluoroelastomer: - as filler, from 2 to 70 phr of silica unwettable with water; - as crosslinking agent, from 0.5 to 10 phr of a bis-olefin having general formula: (I) wherein: R<SUB>1</SUB>, R<SUB>2</SUB>, R<SUB>3</SUB>, R<SUB>4</SUB>, R<SUB>5</SUB>, R<SUB>6</SUB>, equal to or different from each other, are H or C<SUB>1</SUB>-C<SUB>5</SUB> alkyls; Z is selected between a C<SUB>1</SUB>-C<SUB>18</SUB> linear or branched alkylene or cycloalkylene radical, optionally containing oxygen atoms, preferably at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical; the total residual content of metals in the (per)fluoroelastomeric composition being lower than 1,500 ppm, preferably lower than 1,000 ppm.