摘要:
Compositions comprising anionic ionomeric polyurethanes cross-linkable in a wide temperature range, said composition comprising the following components:
I) an aqueous dispersion of a linear crosslinkable ionomeric polyurethane, containing carboxylic groups and having a perfluoropolyether structure; II) a crosslinking agent, the ratio between the equivalents of the functional groups of the crosslinking agent and of the carboxylic groups of component I) being at least 0.7 up to 1.5, preferably 0.9-1.2, said crosslinking agent being dispersible or soluble in the dispersion component I) .
摘要:
A polymer composition formed by: I) fluoropolymers selected from one or more of the following: copolymers based on ethylene, TFE and/or CTFE modified with hydrogenated monomers, or blends of these fluoropolymers with PCTFE; said fluoropolymers and/or the corresponding blends optionally mixed with hydrogenated plasticizers; II) one or more inorganic fire-retardants, treated and not with dispersing agents; III) one or more crosslinking agents; IV) optional additives.
摘要:
Fluoroelastomers curable by ionic route based on vinylidenfluoride (VDF) comprising:
a) 100 parts by weight of fluoroelastomer based on vinylidenfluoride (VDF) substantially polar end group free; b) from 0.05 to 5 phr of accelerant; c) from 0.5 to 15 phr of curing agent; d) from 1 to 40 phr of one or more inorganic acid acceptors, preferably bivalent metal oxides; e) from 0 to 2,5 phr, preferably from 0 to 1.5 phr of one or more basic compounds preferably hydroxides of bivalent metals or of weak acid metal salts; f) from 0 to 80 phr of reinforcing fillers.
摘要:
Compositions based on PTFE, homopolymer or modified, comprising for 100 parts of the component 1) PTFE:
1) an aqueous nanodispersion of said homopolymer or modified PTFE, having a primary particle diameter from 5 to 100 nm; 2) from 3 to 45 parts by weight of a surfactant or surfactant mixtures; 3) from 0.2 to 20 parts by weight of an organic or inorganic sequestrant, and optionally:
4) from 0 to 60 parts by weight of a solid lubricating compound.
摘要:
Semicrystalline sulphonic fluorinated ionomers having an equivalent weight higher than 700 g/eq, up to 1,700, comprising:
(A) monomeric units deriving from one or more fluorinated monomers containing at least one ethylene unsaturation; (B) fluorinated monomeric units containing sulphonyl groups -SO 2 F in such amount to give the above equivalent weight, deriving from F 2 C=CF-O-(CF 2 ) q -SO 2 F, q being an integer-equal to 2 or 3; and having the following properties for a TFE/ (B) copolymer:
hydration, expressed in % of H 2 O at 100°C absorbed by the film prepared from the ionomer and after tranformation from the -SO 2 F form into the -SO 3 H form, having the following values: