Mixtures composed or monocarboxy-functionalized dialkylphosphinic acids, their use and a process for their preparation

Abstract

The invention relates to mixtures composed of monocarboxy-functionalized dialkylphosphinic acids and of further components, which comprise A) from 98 to 100% by weight of monocarboxy-functionalized dialkylphosphinic acids of the formula (I)

Description

Claims

1. A mixture comprising: A) from 98 to 100% by weight of at least one monocarboxy-functionalized dialkylphosphinic acid of the formula (I)

2. The mixture as claimed in claim 1, comprising from 99.9995 to 100% by weight of the at least one monocarboxy-functionalized dialkylphosphinic acids acid of the formula (I) and from 0 to 0.0005% by weight of the at least one halogen.

3. The mixture as claimed in claim 1, wherein the at least one monocarboxy-functionalized dialkylphosphinic acid is 3-(ethylhydroxyphosphinyl)propionic acid, 3-(propylhydroxyphosphinyl)propionic acid, 3-(ethylhydroxyphosphinyl)butyric acid, 3-(ethylhydroxyphosphinyl)-2-methylpropionic acid, 3-(butylhydroxyphosphinyl)-propionic acid, 3-(propylhydroxyphosphinyl)butyric acid, 3-(butylhydroxyphosphinyl)butyric acid, 3-(ethylhydroxyphosphinyl)pentanoic acid, 3-(propylhydroxyphosphinyl)pentanoic acid, 3-(butylhydroxyphosphinyl)pentanoic acid, 3-(propylhydroxyphosphinyl)-2-methylpropionic acid, 3-(butylhydroxyphosphinyl)-2-methylpropionic acid, 3-(ethylhydroxyphosphinyl)-2-methylbutyric acid, 3-(propylhydroxyphosphinyl)-2-methylbutyric acid, 3-(butylhydroxyphosphinyl)-2-methylbutyric acid or a mixture thereof.

4. A process for preparation of a mixture as claimed in claim 1, comprising the the step of reacting hypophosphorous acid or a salt thereof (component C) of the formula II

5. The process as claimed in claim 4, wherein R1, R2, R3, R4, R5, R6, and R7 are identical or different and, independently of one another, are H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, or phenyl.

6. The process as claimed in claim 4, wherein X is H and Z is H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, hydroxyethyl, or hydroxypropyl.

7. The process as claimed in claim 4, wherein, the component C is reacted in the presence of a free-radical initiator with the component E to give an alkylphosphonous acid in a resultant reactant solution, wherein the resultant reaction solution is esterified with an alcohol to form a phosphonous ester in the resultant reaction solution and phosphonous ester produced is removed by distillation and the resultant reaction solution is reacted in the presence of a free-radical initiator or of a basic initiator with component D, hydrolyzing the resultant reaction solution with acidic catalysis, in order to obtain component A, the monocarboxy-functionalized dialkylphosphinic acid.

8. The process as claimed in claim 7, wherein, the alkylphosphonous acid is directly esterified with a linear or branched alcohol of the formula M-OH, where M is a linear or branched alkyl radical having from 1 to 10 carbon atoms.

9. The process as claimed in claim 8, wherein the alcohol is n-butanol, isobutanol, or ethylhexanol.

10. The process as claimed in claim 7, wherein component C is the ammonium or sodium salt of hypophosphorous acid.

11. The process as claimed in claim 4, wherein the at least one free radical initiator is a free-radical, anionic, cationic, or photochemical initiator.

12. The process as claimed in claim 4, wherein the at least one free radical initiator is a peroxide-forming compound, peroxo compound an azo compound or a mixture thereof.

13. The process as claimed in claim 4, wherein the at least one α,β-unsaturated carboxylic acid is acrylic acid, methyl acrylate, ethyl acrylate, methacrylic acid, hydroxyethyl acrylate, crotonic acid, ethyl crotonate, tiglic acid (trans-2,3-dimethylacrylic acid), (trans-)2-pentenoic acid, furan-2-carboxylic acid, thiophene-2-carboxylic acid or a mixture thereof.

14. The process as claimed in claim 4, wherein the at least one olefin is ethylene, propylene, n-butene, isobutene, 1-hexene, 1-heptene, 1-octene; allyl alcohol, allylamine, allylbenzene, allylanisole, styrene, α-methylstyrene, 4-methylstyrene, vinyl acetate or a mixture thereof.

15. The process as claimed in claim 4, wherein the reaction of component C with components D, E or both takes place at a temperature of from 50 to 150° C.

16. A process for preparation of a mixture as claimed in one claim 1, comprising the steps of reacting component C, in a step 1, with a ketone to give 1-hydroxy-1-dialkylphosphinate, reacting this the 1-hydroxy-1-dialkylphosphinate, in a step 2, in the presence of a free-radical initiator with component D, in a step 3, removing the ketone, and reacting the resultant reaction mixture, in a step 4, in the presence of a free-radical initiator with component E.

17. A process for preparation of a mixture as claimed in claim 1, comprising the steps of reacting component C, in a step 1, with a ketone to give 1-hydroxy-1-dialkylphosphinate, reacting the 1-hydroxy-1-dialkylphosphinate, in a step 2, in the presence of a free-radical initiator with component E, in a step 3, removing the ketone, and reacting the resultant reaction mixture, in a step 4, in the presence of a free-radical initiator with component D.

18. A process for preparation of mixtures as claimed in claim 1, comprising the steps of reacting component C, in a step 1, with aceteone to give 1-hydroxy-1-methylethylphosphinate, reacting the 1-hydroxy-1-methylethylphosphinate, in a step 2, in the presence of a free-radical initiator with component E, in a step 3, removing the acetone, and reacting the resultant reaction mixture, in a step 4, in the presence of a free-radical initiator with component D.

19. A flame retardant comprising a mixture as claimed in claim 1.

20. A process for making a flame retardant or a flame retardant article comprising the step of adding a mixture as claimed in claim 1 to the flame retardant or flame retardant article during the manufacture of the flame retardant or the flame retardant article, wherein the flame retardant article is selected from the group consisting of flame retardant molding compositions, flame-retardant moldings, flame-retardant films, flame-retardant filaments, and flame-retardant fibers.

21. The process as claimed in claim 20, wherein the flame-retardant article comprises from 1 to 50% by weight of the mixture, from 1 to 99% by weight of a polymer or a mixture of the same, from 0 to 60% by weight of additives, and from 0 to 60% by weight of filler, where the entirety of the components always amounts to 100% by weight.

22. The process as claimed in 4, wherein the free radical initiator is selected from the group consisting of hydrogen peroxide, sodium peroxide, lithium peroxide, potassium persulfate, sodium persulfate, ammonium persulfate, sodium peroxodisulfate, potassium peroxoborate, peracetic acid, benzoyl peroxide, di-tert-butyl peroxide, peroxodisulfuric acid, azodiisobutyronitrile, 2,2-azobis(2-amidinopropane)dihydrochloride 2,2′-azobis(N,N′-dimethyleneisobutyramidine)dihydrochloride and mixtures thereof.

23. A method for preparing a flame retardant comprising the step of adding a mixture as claimed in claim 1, to the flame retardant during the production of the flame retardant.

24. A flame retardant or flame retardant article made in accordance with the process of claim 20.