Piperazine polyphosphate, methods for its preparation and its use

1 . A piperazine polyphosphate, wherein the piperazine polyphosphate has an average chain length of from 2.2 to 10 phosphate units, and a chain length distribution where:

chain length 1

0.5 to 10%  

chain length 2

2 to 30%

chain length 3

4 to 30%

chain length 4

0 to 90%

chain length 5

1 to 25%

chain length 6

1 to 25%

chain length 7

1 to 40%

chain length 8 and above

0.5 to 40%, 

a 10% strength suspension thereof in water has a pH between 1.5 and 7, the acid number of the filtrate of a 10% strength suspension thereof is between 200 and 400 mg KOH/g and wherein it has a solubility in water of at most 7%.

2 . The piperazine polyphosphate as claimed in claim 1 , wherein the piperazine polyphosphate has the following chain length distribution:

chain length 1

0.5 to 5%  

chain length 2

2 to 20%

chain length 3

4 to 20%

chain length 4

30 to 90% 

chain length 5

1 to 15%

chain length 6

1 to 15%

chain length 7

1 to 30%

chain length 8 and above

0.5 to 30%.

3 . The piperazine polyphosphate as claimed in claim 1 , wherein a 10% strength suspension thereof in water has a pH between 2 and 5.5.

4 . The piperazine polyphosphate as claimed in claim 1 , wherein the acid number of the filtrate of a 10% strength suspension thereof is between 200 and 400 mg KOH/g.

5 . A method for the preparation of piperazine polyphosphate, comprising the step of reacting liquid piperazine, gaseous piperazine or both with polyphosphoric acid.

6 . A method for the preparation of piperazine polyphosphate, comprising the step of reacting polyphosphoric acid with piperazine in the presence of a solvent.

7 . A method for the preparation of piperazine polyphosphate, comprising the step of reacting a salt of an amine base of the polyphosphoric acid in aqueous solution with piperazine.

8 . A flame retardant comprising a piperazine polyphosphate as claimed in claim 1 .

9 . A composition comprising a piperazine polyphosphate as claimed in claim 1 , wherein the composition is in the form of

an intermediate for further syntheses,

a binder,

a crosslinker, and/or accelerator or both during the curing of epoxy resins, polyurethanes or unsaturated polyester resins,

a polymer stabilizers,

a crop protection agent,

a therapeutic or additive in therapeutics for humans and animals,

a sequestrant,

a mineral oil additive,

a corrosion protectant,

a detergent or cleaner application, or

an electronic article.

10 . A flame-retardant thermoplastic or thermosetting polymer molding composition comprising 0.5 to 45% by weight of a piperazine polyphosphate as claimed in claim 1 , 0.5 to 95% by weight of a thermoplastic polymer or a mixture thereof, 0 to 55% by weight of additives and 0 to 55% by weight of filler, strengthening materials, or both, where the sum of the components is 100% by weight.

11 . A flame-retardant thermoplastic or thermosetting polymer molding, film, thread or fiber, comprising 0.5 to 45% by weight of a piperazine polyphosphate as claimed in claim 1 , 0.5 to 95% by weight of a thermoplastic polymer or mixture thereof, 0 to 55% by weight of additives and 0 to 55% by weight of filler, strengthening materials, or both, where the sum of the components is 100% by weight.

12 . A clearcoat or intumescent coating flame retardant comprising a piperazine polyphosphate as claimed in claim 1 .

13 . A flame retardant for wood, cellulosics, plastic, paper or textiles comprising a piperazine polyphosphate as claimed in claim 1 .

14 . A flame retardant for steel coating or wood fire protection comprising a piperazine polyphosphate as claimed in claim 1 .

15 . A flame retardant for polymers, for the production of flame-retardant polymer molding compositions, for the production of flame-retardant polymer moldings, films, threads or fibers comprising a piperazine polyphosphate as claimed in claim 1 .

16 . A flame retardant for the finishing of polyesters or cellulose single and blended fabrics by impregnation comprising a piperazine polyphosphate as claimed in claim 1 .