DD298801A5 - FLAME-RESTRICTED REACTION RESOURCES - Google Patents

Abstract

The invention relates to the use of a mixture for flame retardancy of reaction resin compositions. Reaction resin compositions containing as flame retardants a mixture of a) a hydroxide of a metal of the 2nd or 13th group of the Periodic Table and b) a phosphorus-organic compound of the general formula (I), wherein X is independently oxygen or sulfur, R ind 1 independently Hydrogen, an alkyl radical having 1-4 C atoms or phenyl, R ind 2 independently of one another hydrogen, an alkyl radical having 1-4 C atoms, or R ind 1 and R ind 2 together with the common carbon atom a cyclohexylidene or Cyclohexenylidenring, R ind 3 and R ind 5 independently of one another represent hydrogen or an alkyl radical having 1-4 C atoms, R ind 4 independently of one another represent hydrogen or methyl, where at least one of the substituents R ind 1, R ind 2, R ind 3, R ind 4 and R ind 5 is different from hydrogen, and when R ind 1 and R ind 2 form a ring together with the common carbon atom, R ind 3, R ind 4 and R ind 5 are always hydrogen, are suitable, for example as cladding systems for electrical or electronic components. Formula (I) {Reaction resin composition; Flame retardants; Hydroxides of a metal; organophosphorus compounds; Cladding systems; Electrical components; Electronic components}

Description

X independently oxygen or sulfur, £

R ₁ are each independently hydrogen, an alkyl radical having 1-4 C atoms or phenyl, R _{2 is} independently hydrogen, an alkyl radical having 1-4 C atoms, or ¹ R ₁ and R ₂ together with the common carbon atom a cyclohexylidene or Cyclohexenylidenring,

R ₃ and R ₅ independently of one another represent hydrogen or an alkyl radical having 1-4 C atoms, R ₄ independently of one another represent hydrogen or methyl, where at least one of the substituents R ₁ , R ₂ , R ₃ , R ₄ and R _{5 is} different from hydrogen, and when R ₁ and R _{2 form} a ring together with the common carbon atom, R ₃ , R ₄ and R ₅ always represent hydrogen, is used for flame retardancy of reaction resin compositions.

2. Use according to claim ¹ , characterized in that the reaction resin is an epoxy resin or a polyurethane resin.

3. Use according to claim 1, characterized in that the metal in a) is aluminum or magnesium.

4. Use according to claim 1, characterized in that in the compound of the formula IR ¹ and R ^{2 are} each independently hydrogen or alkyl having 1-4 C atoms; or R ¹ and R ² together with the common C atom represent a cyclohexylidene or cyclohexenylidene ring and R ³ , R ⁴ and R ^{B are} each hydrogen.

5. Use according to claim 4, characterized ^ indicates that in the compound of formula IR ¹ and R ^{2 are} each alkyl having 1-4 carbon atoms.

6. Use according to claim 5, characterized in that in the compound of formula IR ¹ and R ^{2 is} methyl. '

Field of application of the invention

The present invention relates to flame-retarded reaction resin compositions containing a mixture of a metal hydroxide and an organophosphorus compound and the use of such mixtures for flame retardancy of reaction resin compositions.

Characteristic of the known state of the art

Dioxaphosphine oxides are known from US Pat. No. 4,220,472 as flame retardants for polymers, in particular for cellulose. Further, US-A 4,219,607 Hochspannungsisoliermassen that contain a creepage path preventing additive as well as an anti-phosphorus compound containing phosphorus. Furthermore, US Pat. No. 4,668,718 discloses self-extinguishing, creep-resistant epoxy resin molding compositions which contain aluminum hydroxide and calcium phosphate as flame-retardant components.

The flame retardancy of Reaktionsharzrassenassen is generally improved by reducing the organic and thus combustible content; d. H. by adding not resp. flame-retardant fillers such. As quartz powder, glass, wollastonite, etc. However, the filler content must be very high in order to cause sufficient flame retardancy, which often leads to unsolvable problems in the production and processing of the reaction resin compositions.

Another possibility is the addition of flame retardants to the reaction resin compositions. In question come inorganic additives such as boron compounds or metal hydroxides. Again, large amounts of such additives are required, which also has a detrimental effect on the production and processing. The use of halogenating compounds, such as brominated bisphenol A epoxy resins or brominated anhydride, usually in their flame retardant effect by a synergist such. B. Sb ₃ O _{3 are} supported, has the serious disadvantage that in case of fire hydrogen halide is released. This is not only of toxicological concern, but he has an extremely large corrosion potential, which can lead to serious secondary damage by electrochemical corrosion in case of fire of an electrical, but especially an electronic unit.

The use of phosphorus-organic compounds for flame retardancy, which are not incorporated into the reaction resin molding, due to a kind of plasticizer effect, resulting in a significant loss of mechanical and electrical properties of the so flame-retardant treated reactive resin molding materials. For example, the strength values and the glass transition temperature are lowered due to the plasticizing effect of the organophosphorus compound. In addition, these compounds are usually stable to hydrolysis, which leads to an increased water absorption of the reaction resin molding material with simultaneous formation of various phosphoric acid compounds.

Object of the invention

The invention provides mixtures which have improved properties as flame retardants in reaction resin compositions.

Explanation of the essence of the invention

The object of the present invention is to find flame-retardant mixtures which can be used in reaction resin compositions.

It has now surprisingly found a f lambhemmande mixture for use in reaction resin compositions, which does not affect their processability and which leads to an increase in the flame retardancy of the molding materials, but without affecting their properties, such as thermal stability, mecnanische strength or water absorption, adversely. The present invention relates to reactive resin compositions containing as flame hammers a mixture of

a) t'nem hydroxide of a metal of the 2nd or 13th group of Pei iodensystems and

b) a phosphorus-organic compound of general formula I.

(I), R ₂

X is independently oxygen or sulfur,

Ri independently of one another hydrogen, an alkyl radical having 1-4 C atoms or phenyl, R ₂ independently of one another hydrogen, an alkyl radical having 1-4 C atoms, or R, and R ₂ together with the common C atom a cyclohexylidene or Cyclohexenylidene ring, R _{3, and} independently of each other, hydrogen or an alkyl radical, C atoms,

R ₄ independently represent hydrogen or methyl, wherein at least one of the substituents R ₁ , R ₂ , R ₃ , R ₄ and R _{6 is} different from hydrogen, and when R ₁ and R _{2 form} a ring together with the common carbon atom , R ₃ , R ₄ and R ₆ always represent hydrogen. ^

If R ¹ , R ² , R ³ and R ^{6 are} an alkyl radical having 1-4 C atoms, then this radical may be branched or straight-chain and

for example, methyl, ethyl, n-propyl, isopropyl, η-butyl, sec-butyl, isobutyl or tert. Butyl, but preferably methyl or

Ethyl, especially methyl, t ^ interpret. Preference is given to compounds of the formula I in which R ¹ and R ² each independently of one another are hydrogen or alkyl

1-4 C atoms, or R ¹ and R ² together with the common carbon atom, a cyclohexylidene or Cyclohexenylidenring and

R ³ , R ⁴ and R ^{5 are} each hydrogen. Particular preference is given to compounds of the formula I in which R ¹ and R ^{2 are} each alkyl having 1-4 C atoms, in particular methyl,

mean.

Very particular preference is given as compounds of the formula I bis (2-thio-5,5-dimethyl-1,3,2-dioxaphosphinan-2-yl) oxide and Bis (2-oxo-5,5-dimethyl-1,3,2-dioxaphosphinan-2-yl) oxide used. The designation of the groups of the feriodene systom corresponds to the new notation as described in Chem. And Eng. News 63 (5), 27,

(1985).

The metal hydroxides in question as component a) of the flame-retardant mixture are e.g. magnesium hydroxide, Calcium hydroxide, boron hydroxide or aluminum hydroxide. Preference is given to magnesium hydroxide and aluminum hydroxide or

a mixture of the two hydroxides.

The preparation of the components a) and b) of the flame-retardant mixture is carried out by methods known per se. The Metal hydroxides are usually commercially available. The phosphorus-organic compounds may, for. B. after in the US-A 4,220,472 are described and are also z.T. available in the stores. The amount of the individual components, based on the total weight of the reaction resin composition, is expedient for the Component a) up to 70% by weight, but preferably 20-60% by weight, in particular 30-50% by weight; and for component b)

2-40% by weight, but preferably 2-20% by weight, especially 5-15% by weight. The content of components a) and b) together is at most 85% by weight, preferably 70% by weight, based on the total weight of the reaction resin composition.

The mixture according to the invention is very suitable as a flame retardant for reaction resin compositions. Especially suitable as Reaction resins are epoxy resins and polyurethane resins. The inventively flame-retarded reaction resin compositions

are preferably used or find as enclosure systems for electrical or electronic potting systems

Use in epoxy or polyurethane foams. It may be in the reaction resin composition to liquid or

act powdered masses.

As epoxy resins are all types of epoxy resins, such as those directly to oxygen, nitrogen or Sulfur atoms bound groups of the formula

-CH- C-CH R 'R "R"

R " ¹

wherein either R 'and R "' each represent a hydrogen atom, in which case R" then represents a hydrogen atom or a methyl group, or R 'and R "' together represent -CH ₂ CH ₂ - or -CH ₂ CH ₂ CH ₂ - in which case R "then signifies a hydrogen atom.

Examples of such resins include polyglycidyl and poly (β-methylglycidyl) esters, which can be obtained by reacting a compound containing 7 or more carboxylic acid groups per molecule with epichlorohydrin, glycerol dichlorohydrin or β-methylepichlorohydrin in the presence of alkali. Such polyglycidyl esters may differ from aliphatic polycarboxylic acids, e.g. Oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid or dimerized or the like. ' trimerized linoleic acid, derived from cycloaliphatic polycarboxylic acids such as tetrahydrophthalic acid, 4-methyltetrahydrophthalic acid, hexahydrophthalic acid and 4-methylhexahydrophthalic acid and from aromatic polycarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid.

Further examples are polyglycidyl and poly (.beta.-methylglycidyl) ethers which are obtained by reacting a compound containing at least two free alcoholic and / or phenolic hydroxyl groups per molecule with the corresponding epichlorohydrin under alkaline conditions or else in the presence of an acidic catalyst with following Alkali treatment, are available. These ethers can be mixed with poly (epichlorohydrin) from acyclic alcohols such as ethylene glycol, diethylene glycol and higher poly (oxyäthylen) glycols, propane-1,2-diol and poly (oxypropylene) glycols, propane-1,3-diol , Butane-1,4-diol, poly (oxytetramethylene) -glycols, pentane-1,5-diol, hexane-1,6-diol, hexane-2,4,6-triol, glycerol, 1,1,1 Trimethylolpropane, pentaerythritol and sorbitol, from cycloaliphatic alcohols such as resorcite, quinitol, bis (4-hydroxycyclohexyl) methane, 2,2-bis (4-hydroxycyclohexyl) -propane and ii-bis-lhydroxymethyl-cyclohexene-S- and from alcohols with aromatic nuclei such as N, N-bis (2-hydroxyethyl) -aniline and p, p'-bis- {2-hydroxyethylamino) -diphenylmethane. They can also be obtained from mononuclear phenols such as resorcinol and hydroquinone, and polynuclear phenols such as bis (4-hydroxyphenyl) methane, 4,4-dihydroxydiphenyl, bis (4-hydroxyphenyl) sulfone, 1,1,2,2-tetrakis - (4-hydroxyphenyl) -ethane, 2,2-bis (4-hydroxyphenyl) -propane (otherwise known as bisphenol A) and 2,2-bis (3,5-dibromo-4-hydroxyphenyl) -propane, as well as from aldehydes such as formaldehyde, acetaldehyde, chloral and furfurol, prepared with phenols such as phenol itself and by chlorine atoms or alkyl groups each having up to nine carbon atoms ring-substituted phenol such as 4-chlorophenol, 2-methylphenol and 4-tert-butylphenol novolacs.

Poly (N-glycidyl) compounds include, for example, those obtained by dehydrochlorinating the reaction products of epichlorohydrin with amines containing at least two amine oxygen atoms, such as aniline, n-butylamine, bis (4-aminophenyl) methane and bis (4-methyl -narninophenyl) -methane, triglycidyl isocyanurate and Ν, Ν'-diglycidyl derivatives of cyclic alkylene ureas such as ethylene urea and 1,3-propylene urea, and hydantoins such as 5,5-dimethylhydantoin.

Poly-IS glycidyl compounds are, for example, the di-S-glycidyl derivatives of dithiols such as ethane-1,2-dithiol and bis (4-mercaptomethylphenyl) ether

Examples of epoxy resins with groups of formula _x

-CH-A

-CH-C ^: - CH R ¹ R "R ¹ "

in which R 'and R "' together denote a -CH ₂ CHa group are bis (2,3-epoxycyclopentyl) ether, 2,3 · Epoxycyclopentylglycidyläther, 1,2-bis (2,3-epoxycyclopentyloxy) - Ethane and 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate. Also contemplated are epoxy resins in which the 1,2-epoxide groups are bonded to heteroatoms of various types, for example the Ν, Ν, Ο-triglycidyl derivative of 4-aminophenol, the Glycidyl ether / glycidyl ester of salicylic acid or p-hydroxybenzoic acid, N-glycidyl-N '- (2-glycidyloxypropyl) -5,5-dimethylhydantoin and 2-glycidyloxy-1,3-bis (5,5-dimethyl-1-glycidylhydantoinyl) 3) propane.

If desired, one can use epoxy resin mixtures.

Preferred epoxy resins are the polyglycidyl ethers, polyglycidyl esters and Ν, Ν'-diglycidylhydantoins. Especially preferred resins are the polyglycidyl ethers of 2,2-bis- (4-hydroxyphenyl) -propane, of bis- (4-hydroxy-) -methane or of formaldehyde and unsubstituted or substituted by an alkyl group of 1-9 C-atoms Phenol Novolak formed with a 0,5val / kg exceeding 1,2-epoxide content.

Suitable polyurethane resins are, for example, those which contain polyfunctional isocyanates and / or polyurethane prepolymers as the main constituent. Suitable here are both aromatic and aliphatic, monocyclic and polycyclic, polyfunctional isocyanate compounds such as hexane-1,6-diisocyanate, cyclohexane-1,3-diisocyanate and isomers, 4,4'-dicyclohexylmethane diisocyanate, 3-isocyanatomethyl-3,5, 5-trimethylcyclohexyl isocyanate, 1,3-dimethylbenzene, diisocyanate and isomers, 1-methylbenzene-2,4-diisocyanate and isomers, naphthalene-1,4-diisocyanate,

Diphenyl ether, 4,4'-diisocyanate and isomers, Diphonylsulfon-4,4-diisocyanate and isomers and tri or höHrfunktionelle Isocyanates, such as S.S '^^' - Diphenylmethantetraisocyanat. Furthermore, it is also possible to use isocyanates which

masked in the usual way with phenol, krssol or caprolactam. Dimers and trimers of said polyvalent ones

Isocyanates are also usable. Such polyisocyanates have terminal free isocyanate groups and contain one

or more uretdione and / or isocyanurate rings. Process for the preparation of various types of such trimers and

Uretdiones are described, for example, in U.S. Patents 3,494,888,3108100 and 2,977,370. Further usable polyisocyanates are, for example, tolylene diisocyanate or diphenylmethane diisocyanate. Especially

is suitable technical diphenylmethane diisocyanate containing higher-functional diisocyanates and a

Functionality of isocyanate groups greater than 2. Another suitable aliphatic diisocyanate is xylylene diisocyanate. In addition, a variety of aliphatic isocyanates of functionality 2 and higher can be used. According to another embodiment, polyurethane prepolymers are used instead of the polyfunctional isocyanate compounds

used. Among prepolymers here are the adducts of an excess of polyfunctional isocyanates to polyfunctional

Alcohols, such as the Umseüungsprodukte one of the aforementioned aromatic or aliphatic diisocyanates with Ethylene glycol, Propyleng'ykol, glycerol, trimethylolpropane or pentaerythritol understood. Also, reaction products of Diisocyanates with polyether polyols, eg. As polyether polyols based on polyethylene oxide or based on polypropylene oxide

be used as prepolymers. Preference is given to polyurethane prepolymers based on polyether polyols with

Molar weights between 200 and 10,000, in particular 500 and 3000. The polyurethane specialist are a large number

known such polyether polyols; They are offered by numerous manufacturers and characterized by their molecular weight (number average), which can be calculated from end-group determinations. Other suitable polyether polyols are

Polyether polyols based on polytetrahydrofuran. Instead of polyether polyols and polyester polyols can be used. Suitable polyester polyols are Reaction products of polyfunctional acids with polyhydric alcohols, such as polyester based

aliphatic and / or aromatic dicarboxylic acids and polyfunctional alcohols of functionality 2-4. So can

Polyesters of adipic acid, sebacic acid, phthalic acid, hydrophthalic acid and / or trirnellic acid on the one hand and ethylene glycol, Propylene glycol, neopentyl glycol, hexane glycol, glycerol and / or trimethylolpropane, on the other hand. Suitable

Particularly suitable polyester polyols are the reaction products of caprolactone with alcohols having the functionality of 2-4, such as the addition product of 1-5 moles of caprolactone to 1 mole of ethylene glycol , Propylene glycol, glycerol and / or trimethylolpropane.

Another suitable class of polyfunctional alcohols are polybutadienols. These are based on oligomers Butadiene, which have OH groups as end groups. Suitable here are products in the molecular weight range 200-4000,

especially 500-3000.

In the preparation of the polyurethane prepolymers, the ratio of OH groups of the alcohol component is too Isocyanate groups of importance. This is generally between 1: 2 and 1:10. It will be with higher Isocyanate excess rather low viscosity polyurethane prepolymers obtained while lower isocyanate excess

deliver highly viscous, usually only fillable preparations.

It is known to the polyurethane specialist that the crosslinking density and thus the hardness of the polyurethanes with the Functionality of the isocyanate component or the polyol increases. Please refer to the general literature here,

z. See, for example, the monograph of Saunders and Frisch "Polyurethanes, Chemistry and Technology", Volume XVI of the High series

Polymer's "Interscience Publishers" New York-London, Part I (1962) and Part II (1964). The preparation of the reaction resin compositions according to the invention can be carried out in customary manner with the aid of known mixing units (eg. Extruder, stirrer, kneader, roll mills, mills). The processing into moldings of all kinds can be carried out by conventional methods under curing. Particularly suitable is the Processing by the casting process or by the vacuum casting process. embodiments Initially, 3 master pastes are produced, which are used in different quantities. Stock paste 1:

60g Sandoflam® 5060 (from Sandoz Hunlngue, France) of the formula

CH ₃ . .CH ₂ O _x .OCH _2x , CH ₃

\ / P-O-P C

j-iiT '/ "¹Uf \Ilc \ r * XX / "U *

together with 100 g of a liquid at room temperature, unmodified epoxy resin based on sisphenol A and epichlorohydrin having an epoxide content of 5.25-5.40 equiv. / kg on a roll mill (type DH-3 from Drais, Germany) intensively mixed into a master batch.

Stock paste 2:

60g Sandoflam® 5080 (from Sandoz Huningue, France) of the formula

CH _3x , CH ₂ O _x .OCH ₂ . .CH ₃

VP ₁ -OP ^

CH / ^N CH ₂ O ^/ I1 1 ^X OCH ₂ CH ₃

together with 100g of a liquid at room temperature, unmodified epoxy resin based on bisphenol A and epichlorohydrin having an epoxide content of 5.25-5.40 equiv. / kg on a roll mill (type DH-3 from Drais, Germany) intensively mixed into a master batch.

Stock paste 3:

10 g of the thixotropic agent Silica R202 (from Degussa, Germany) are mixed with 90 g of a room temperature liquid, unmodified epoxy resin based on bisphenol A and epichlorohydrin with an epoxide content of 5.25-5.40 equiv. / Kg on a roll mill ( Type DH-3 from Drai.3, Germany) mixed intensively into a master batch.

example 1

61.3 g of stock paste 1 (containing 23 g of Sandoflam® 5060 and 38.3 g of epoxy resin) and 177 g of aluminum hydroxide (Apyral® 2 of the

United Aluminum Werke AG, Germany) are charged with 61.7 g of a liquid at room temperature and unmodified Epoxy resin based on bisphenol A and epichlorohydrin with an epoxide content of 5.25-5.40 equiv. / Kg by means of Dissolver mixer homogenized. This flame-retardant resin composition is degassed under vacuum (about 15 min at

ρ = 5mbar / pump capacity approx. 40l / min; Temperature of the resin composition T = 8O ⁰ C).

This resin composition is mixed with 90 g of a low-viscosity anhydride hardener based on methyltetrahydrophthalic anhydride

mixed intensively with a paddle stirrer. This flame-retardant reaction resin composition is degassed under vacuum (about 15 minutes at ρ = smbar / pump capacity about 40 l / min, temperature of the mass T ~ 80 ° C). Subsequently, in 1.6 mm or 3.2 mm preheated plate forms shed. Curing is carried out for 1 hour at 100 ° C and 3 h at 12O ⁰ C.

Example 2 Analogously to the method of Example 1 are used:

41.3 g master paste 1 74.3 g epoxy resin 119.0 g aluminum hydroxide (Apyral ⁹ 2)

After evacuating this resin composition according to Example 1, 30.0 g of a low-viscosity, cycloaliphatic polyamine hardener based on S '' - dimethyl ^^ '- diaminodicyclohexyl methane are added.

This flame-retardant reaction resin composition is degassed under vacuum (about 15 minutes at ρ = 5 mbar / pump capacity about 40 l / min, temperature of the mass T = 6O ⁰ C). Subsequently, in 1.6 mm or 3.2 mm preheated plate forms shed. Curing is carried out for 1 h at 60 ° C and 2 h at 12O ⁰ C.

Example 3 Analogously to the method of Example 1 are used:

61.3 g master paste 2 30.0 g master paste 3 34.7 g epoxy resin 177.0 g aluminum hydroxide (Apyral® 2)

After evacuating this resin composition according to Example 1, 90.0 g of a low-viscosity anhydride hardener based on methyltetrahydrophthalic anhydride are thoroughly mixed with a paddle stirrer.

This flame-retardant reaction resin composition is degassed under vacuum (about 15 minutes at ρ = 5 mbar / pump capacity about 40 l / min, temperature of the mass T = 8O ⁰ C). Subsequently, in 3.2mm preheated plate forms are poured. Curing is carried out for 1 hour at 100 ° C and 3 h at 12O ⁰ C.

Example 4 After demolding, the specimens of Examples 1-3 are combustible according to the Underwriters Ncrm Laboratories Inc. UL 94, third edition (revision) of 25th Sept. 1981 (horizontal flammability test) tested. 3 specimens of 127 χ 12.7 x 1.6 mm are used as samples. Furthermore, the glass transition temperature is determined by means of the DSC method (Differential Sc inning calorimetry). The results are shown in Table 1. Table 1

example 1 2 3 Flame retardant to UL at 1.6 mm HB HB HB Flame retardant to UL at 3.2 mm V-O V-O V-O Glass transition temperature Tg [ ⁰ C] 124 118 125 Filler content total [wt .-%] 51.00 49,20 51,60 AI (OH) content [wt .-%) 45,00 43,50 45,00 P content [wt .-%] 1.05 1.02 1.05

Example 5

100g of trifunctional polyether polyol (Baygal® K55 from Bayer AG, Germany) are "drained" about 90 minutes at a temperature of 110 ⁰ C and then until free of bubbles (5 mbar, 5 minutes) evacuated. After cooling 180g aluminum hydroxide ( Apyral ⁹ 2 from Vereinigte Aluminiumwerke AG, Germany) and 20 g Sandoflam ⁹ 5060 (from Sandoz Huningue, France) were intensively stirred in and this resin mass was evacuated (about 10 minutes at ρ = 5 bpm / pumping capacity about 40 l / min, temperature of the mass T = 40 ° C).

This filled resin component is mixed with the hardener, 25 g of methane-diphenyidiisocyanate (Baymidur * K88 from Bayer AG, Germany) intensively mixed and evacuated (about 10 minutes at ρ = 5 mbar / pump capacity about 40 l / min, temperature of the mass Subsequently, this reaction resin composition in 3 mm plate shapes (mold temperature about 2O ⁰ C) is poured and 15 h at 4O ⁰ C.

hardened.

After demolding, the test specimens are tested for flammability according to the Limiting Oxygen Index (ASTM 2683-77). Result: Limiting Oxygen Indox: 30.2.

Claims (1)

1. Use of a mixture for flame retardancy, characterized in that a mixture of a) a hydroxide of a metal of the 2nd or 13th group of the periodic table and b) a phosphorus-organic compound of general formula I. R _c V ^ ^{x X} \ ^y \ ~ / Na W \ n ' (I), R ₂ / \