Vulcanizable compositions based on copolymers of vinylidene fluoride and containing vulcanization accelerators which are aminophosphinic compounds

Vulcanizable compositions consisting of:

• (I) 100 parts by weight of an elastomeric copolymer of vinylidene fluoride, with at least one fluorinated or chlorofluorinated, ethylenically unsaturated monomer;
• (II) 1-40 parts by weight of an acceptor of inorganic acid, consisting of at least one basic oxide of a bivalent metal, selected from the group consisting of magnesium oxide, calcium oxide, lead monooxide, zinc oxide and/or at least one basic lead phosphite;
• (III) 0.5-10 parts by weight of at least one basic compound selected from the group consisting of calcium, strontium, barium, sodium and potassium phosphates;
• (IV) 0.5-15 parts by weight of a vulcanizing agent based on at least one polyhydroxyl and/or polythiol compound of general formulae:
• A(XZ).sub.n and/or ZX--R--XZ
• wherein A is an arylene radical;
• n is a whole number equal to at least 2;
• X is oxygen or sulphur;
• Z is hydrogen or an alkaline metal;
• R is an alkylene, cycloalkylene, mono- or polyalkylencycloalkyl, alkylendiaryl or oxoalkylendiaryl radical;
• and
• (V) 0.05-5 parts by weight of a vulcanization accelerator which is an aminophosphinic derivative of the general formulae:
• ##STR5## wherein:
• R', R" and R'", the same or different, are alkyl, cycloalkyl, aryl, arylalkyl, oxyalkyl or polyoxyalkyl groups having a free or etherified terminal OH function and containing from 1 to 18 carbon atoms;
• such an alkyl, cycloalkyl, aryl, arylalkyl, oxyalkyl or polyoxyalkyl group substituted by halogen, CN, OH or carbalkoxy;
• or such alkyl, cycloalkyl, aryl, arylalkyl, oxyalkyl or polyoxyalkyl groups in which R' and R" together form, with the nitrogen atom, a heterocyclic ring;
• q is a whole number comprised between 1 and 3;
• R.sup.iv is hydrogen, an alkyl group containing from 1 to 16 carbon atoms, or a carbalkoxy group --COOR in which R is a C.sub.1 -C.sub.8 alkyl;
• R.sup.v is a carbalkoxy group --COOR in which R is a C.sub.1 -C.sub.8 alkyl, the --CN group, the --CONH.sub.2 group, a C.sub.1 -C.sub.16 alkyl group, or an aryl group;
• or
• R.sup.iv and R.sup.v form, with the carbon atom, the cyclic group ##STR6## R.sup.vi is an aryl group, a carbalkoxy group --COOR in which R is a C.sub.1 -C.sub.8 alkyl, a carbaryloxy group --COOAr in which Ar is aryl;
• or R.sup.vi is an ionic group having one of the formulae:
• ##STR7## wherein:
• R', R", R"' have the same meanings as in formulae (I) and (II);
• R is a bivalent alkylenic, arylenic or oxoalkylenic radical;
• n is a whole number comprised between 1 and 4;
• r is a whole number comprised between 1 and 3;
• m is a whole number comprised between 1 and 3, corresponding to the valence of anion Y;
• m.p.=2, and
• Y is an organic or inorganic anion of valency m.