Flame-retardant composition comprising a phosphonic acid derivative

1. A blend comprising a synergistic mixture of (A) and (B), wherein:

(A) is a chemical compound or a mixture of two or more chemical compounds selected from the group consisting of

a) one or more phosphonate compound(s) according to the following formula

wherein A 1 and A 2 are each independently of the other a substituted or unsubstituted straight chain or branched chain alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted benzyl, a substituted or unsubstituted phenyl, or a substituted or unsubstituted naphthyl, and

b) alkyl- or aryl-phosphonic acids, wherein alkyl- is a straight chain or branched chain alkyl group having 1 to 4 carbon atoms, and aryl is a substituted or unsubstituted benzyl, substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or a salt respectively an ester of the aforesaid phosphonic acid, and

(B) is a 1,3,5-triazine compound or a mixture of two or more 1,3,5-triazine compounds selected from the group consisting of hindered amine compounds of the formula I, II, IIA and III:

R 1 NH—CH 2 CH 2 CH 2 NR 2 CH 2 CH 2 NR 2 CH 2 CH 2 CH 2 NHR 4   (I)

T-E 1 -T 1   (II)

T-E 1   (IIA)

G-E 1 -G 1 -E 1 -G 2   (III),

where in the tetraamine of formula I

R 1 and R 2 are the s-triazine moiety E; and one of R 3 and R 4 is the s-triazine moiety E, with the other of R 3 and R 4 being hydrogen,

wherein E is

R is methyl, cyclohexyl or octyl,

R 5 is alkyl of 1 to 12 carbon atoms,

wherein in the compound of formula II or IIA, when R is cyclohexyl or octyl,

T and T 1 are each a tetraamine substituted by R 1 -R 4 as defined for formula I,

where

(1) one of the s-triazine moieties E in each tetraamine is replaced by the group E 1 which forms a bridge between two tetraamines T and T 1 ; car

(2) the group E 1 can have both termini in the same tetraamine T as in formula IIA where two of the E moieties of the tetraamine are replaced by one E 1 group, or

(3) all three s-triazine substituents of tetraamine T can be E 1 such that one E 1 links T and T 1 and a second E 1 has both termini in tetraamine T, and

E 1 is

and L denotes propanediyl, cyclohexanediyl or octanediyl;

G, G 1 , and G 2 are each tetraamines substituted by R 1 -R 4 as defined for Formula J, except that G and G 2 each have one of the s-triazine moieties E replaced by E 1 , and G 1 has two of the triazine moieties E replaced by E 1 , such that there is a bridge between G and G 1 and a second bridge between G 1 and G 2 .

2. The blend according to claim 1 , wherein the phosphonate compound being a compound of the following formula

3. The blend according to claim 1 or 2 , further comprising N,N′,N′″-tris{2,4-bis[(1-hydrocarbyloxy-2,2,6,6-tetramethylpiperidin-4-yl)alkylamino]-s-triazin-6-yl}-3,3′-ethylenediiminodipropylamine and N,N′,N″-tris-{2,4-bis[(1-hydrocarbyloxy-2,2,6,6-tetramethylpiperidin-4-yl)alkylamino]-s-triazin-6-yl}-3,3′-ethylenediiminodipropylamine.

4. The blend according to any one of claims 1 to 3 , wherein the phosphonate compound(s) (A) and the 1,3,5-triazine compound(s) (B) are in a ratio of 1:100 up to 100:1.

5. A flame-retardant composition comprising a mixture according to any one of claims 1 to 4 including one or more further component(s), selected from the group consisting of pigments, colorants, softeners, antioxidants, phenolic antioxidants, thixotropic agents, levelling agents, basic co-stabilizers, nitrone stabilizers, amine oxide stabilizers, benzofurane stabilizers, UV-absorbing agents, sterically hindered amines, metal deactivators, metal oxides, hydroxyl amines, drop inhibitors, calcium stearate, zinc stearate, phosphite- and phosphonite stabilizers, benzofuranone stabilizers, UV-absorbing agents of the 2-(2′-hydroxyphenyl)benzotriazole and 2-(2-hydroxyphenyl)-1,3,5-triazine classes, sterically hindered amines and radical formers and mixtures thereof.

6. The polymer moulding material comprising a flame-retardant composition according to claim 5 .

7. A process to provide flame retardant properties to a polymer according to claim 1 , whereby the process comprises the addition of

a) one or more phosphonate compound(s) and

b) one or more 1,3,5-triazine compound (s).

8. The process according to claim 7 further comprising the addition of a radical former.

9. The polymer, containing a flame-retardant composition according to claim 5 .

10. The polymer according to claim 9 , said polymer being selected from the group consisting of polyolefins, polyesters, polyamides, ABS-polymers, polypropylene, polyethylene, thermoplastic olefin (TPO), high impact polystyrene, thermoplastic polyurethane-elastomers (TPU), polyvinyl chloride (PVC), polyvinyl acetate (PVA), ethyl-vinyl acetate (EVA), polyester resins (UP-Resins), polyurea and polyurethanes or mixtures of two or more thereof.

11. Articles containing a polymer according to claim 9 or 10 , selected from fibres, films, foils, molded objects, and foamed molding products.