Abstract: Fluorinated polyurethanes and polyurethane-ureas, of heat-processable, elastomeric type, constituted by rubber-like blocks and hard blocks, comprising segments derived from:(a) a macroglycol or polybutadiene-diol;(b) a perfluoropolyether-diol of formulaHO(CH.sub.2 CH.sub.2 O).sub.n --CH.sub.2 --Q--CH.sub.2 --(OCH.sub.2 CH.sub.2).sub.n OHwherein Q is a perfluoropolyether chain and "n" is comprised within the range of from 1 to 5;(c) an aromatic, aliphatic, or cycloaliphatic diisocyanate; and(d) an aliphatic, cycloaliphatic or aromatic diol or diamine, containing from 2 to 14 carbon atoms.They contain from 4 to 30% by weight of fluorine, from 10 to 60% by weight of hard components, with the molar ratio of rubber-like components (a): (b) comprised within the range of from 2 to 20. At least 80% of rubber-like segments deriving from (b) component are connected, at least at one of their sides, through a segment deriving from (c) component, with a rubber-like segment deriving from (a) component.

Abstract: Fluorinated polyurethanes containing blocks having a perfluoropolyethereal structure, with rubber-like properties, alternated with stiff structural units are taught. The stiff units are at least partially provided with a double bond of the olefinic type, which is suitable for causing the cross-linking of the polymeric chains with a cross-linking system of the radicalic type.

Abstract: The invention relates to polyurethanes comprising polyoxyperfluoroalkylene blocks of rubber-like nature and rigid segments derived from short-chain aliphatic diols, optionally from aliphatic diamines, and from aliphatic or cycloaliphatic or aromatic diisocyanate. The number of the rigid-type segments is equal to or greater than the number of the polyoxyperfluoroalkylene blocks. The polyurethane are characterized by a glass transition temperature lower than -80.degree. C., a tensile strength greater than 30 kg/cm.sup.2, a hardness between 50 Shore A and 75 Shore D, and good thermoforming characteristics.