Self-extinguishing cable and fire retardant composition used therein
AssigneePirelli Cavi e Sistemi S.p.A.
InventorsCristiana Scelza, Antonio Zaopo
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Abstract
The invention concerns a self-mixing using cable, in particular for the distribution of electric power, wherein at least conductor-coating layer comprising a fire retardant composition is present. Such a composition comprises a base polymer material in admixture with predetermined amounts of melamine or a derivative thereof, red phosphorous, magnesium and/or aluminium hydroxide and a zeolite and allows to obtain cables endowed with improved self-extinguishing properties.
Claims16
A self-extinguishing cable comprising at least one conductor and at least a coating layer comprising a fire retardant composition comprising:
- (a) a polymer base material;
- (b) melamine or a derivative thereof, in amounts equal to 5-50 parts by weight;
- (c) red phosphorus, in amounts equal to 5-50 parts by weight;
- (d) magnesium and/or aluminium hydroxide or hydrated oxide, in amounts equal to 10-150 parts by weight;
- (e) a zeolite in amounts equal to 1-5 parts by weight;
- said amounts being referred to 100 parts by weight of component (a).
A cable according to anyone of the preceding claims, wherein component (a) is selected from the group consisting of polypropylene;
- thermoplastic copolymers of propylene with ethylene or another olefin;
- copolymers of ethylene with at least an ester selected from alkylacrylates, alkylmetacrylates and vinylcarboxylates, wherein the alkyl group, linear or branched, may have from 1 to 8 carbon atoms, whereas the carboxyl group, linear or branched, may have from 2 to 8 carbon atoms;
- elastomeric copolymers ethylene/alpha-olefins;
- and mixtures thereof.
A cable according to anyone of the preceding claims, wherein the melamine derivative is selected from the group consisting of guanamines or melamine phosphates, borate, sulphate or cyanurate.
A cable according to anyone of the preceding claims, wherein the zeolite has the formula:
- Mx/n[(AlO2)x,(SiO2)y].wH2O
- wherein
- M represents an alkali or earth-alkali metal cation or tetralkylammonium;
- x, y and w are integer numbers, the y/x ratio being a number greater than or equal to 1;
- n is the cation valence.
A cable according to anyone of the preceding claims, wherein components (b), (c), (d) and (e), are present in amounts equal to 10-30, 10-30, 20-100 and 1,5-3 parts by weight, respectively.
A fire retardant composition comprising a base polymer composition comprising:
- (a) a polymer base material;
- (b) melamine or a derivative thereof, in amounts equal to 5-50 parts by weight;
- (c) red phosphorus, in amounts equal to 5-50 parts by weight;
- (d) magnesium and/or aluminium hydroxide or hydrated oxide, in amounts equal to 10-150 parts by weight;
- (e) a zeolite in amounts equal to 1-5 parts by weight;
- said amounts being referred to 100 parts by weight of component (a).
A composition according to claim 10 or 11, wherein component (a) is selected from the group consisting of high density polyethylene, medium density polyethylene, low density polyethylene;
- copolymers of ethylene with alpha-olefins having from 3 to 12 carbon atoms.
A composition according to anyone of the claims from 9 to 11, wherein component (a) is selected from the group consisting of polypropylene;
- thermoplastic copolymers of propylene with ethylene or another olefin;
- copolymers of ethylene with at least an ester selected from alkylacrylates, alkylmetacrylates and vinylcarboxylates, wherein the alkyl group, linear or branched, has from 1 to 8 carbon atoms, whereas the carboxyl group, linear or branched, has from 2 to 8 carbon atoms;
- elastomeric copolymers ethylene/alpha-olefins;
- and mixtures thereof.
A composition according to anyone of claims from 9 to 12, wherein the copolymers of ethylene with at least one ester are selected from copolymers ethylene/vinylacetate, ethylene/ethylacrylate, ethylene/butylacrylate.
A composition according to anyone of claims from 9 to 13, wherein the melamine derivative is selected from the group consisting of guanamines or melamine phosphates, borate, sulphate or cyanurate.
A composition according to anyone of claims from 9 to 14, wherein the zeolite has the formula:
- Mx/n[(AlO2)x,(SiO2)y].wH2O
- wherein
- M represents an alkali or earth-alkali metal cation or tetralkylammonium;
- x, y and w are integer numbers, the y/x ratio being a number greater than or equal to 1;
- n is the cation valence.
A composition according to anyone of claims from 9 to 15, wherein components (b), (c), (d) and (e), are present in amounts equal 10-30, 10-30, 20-100 and 1,5-3 parts by weight, respectively.
Dependencies are inferred from the claim text.