AT509959B1 - FLAME-PROOF EXPANDABLE POLYMERISATE - Google Patents

Abstract

The invention relates to flame-retardant, at least one blowing agent-containing, expandable polymers and polymer foams and processes for the preparation thereof, wherein as flame retardants at least one phosphorus compound of the following general formula (I) or (II), or ring-opened hydrolysates or salts thereof, is characterized characterized in that they are (II) 9,10-dihydro-10-mercapto-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt ("OOPS-SNH (Et) 3"), 9,10-Dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt ("DOPS-ONH (Eth"), 9,10-dihydro-10-hydroxy-9- oxa-10-phosphaphenanthrene-10-thione or -10-sulfide melamine salt ("DOPS-OMel"), 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione and -10, respectively sulfido guanidinium salt ("DOPS-OGua"), bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide ("DOPS-S-DOPS"), bis (9, 10 -dihydro-9-oxa-10-phospha-10 thioxophenanthren-10-yl) dis ulfide ("OOPS-S2-DOPS") and / or bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) tetrasulfide ("DOPS-S4-DOPS").

Description

The present invention relates to flame-retardant, at least one blowing agent-containing, expandable polymers containing at least one new derivative of 9,10-dihydro-9-oxa-10-phosphaphenanthren-10-one or 10-oxide as flame retardants ,

The invention further relates to these flame retardants protected polymer foams, processes for producing the same, and the particular use of the above flame retardants in expandable polymers and polymer foams.

STATE OF THE ART

9,10-Dihydro-9-oxa-10-phosphaphenanthren-10-one or 10-oxide (DOPO)

Is a well-known and common flame retardant since the early 1970s and was first developed by Sanko Chemical Co. ltd. described in DE 20 34 887. In this document, a group of 9,10-dihydro-9-oxa-10-phosphaphenanthrene derivatives of the following formulas is generally disclosed:

Wherein the compounds of the latter formula are the products of ring-opening hydrolysis and in which the symbols have the following meaning: [0006] Z is oxygen, sulfur or absent; X is hydrogen, chlorine, methyl or phenoxy; Y is hydrogen, chlorine or C-M-alkyl; and [0009] n = 0, 1 or 2.

Furthermore, this document discloses the preparation of the compounds by reacting o-phenylphenol derivatives with phosphorus trichloride, triphenyl phosphite, phenoxydichlorophosphin or diphenoxychlorophosphine and their use (inter alia) as flame retardants. The only sulfur-containing derivative in the examples is " DOPS-OPh " prepared and analyzed according to the following reaction:

The abbreviation " DOPS " for the sulfur analog of DOPO, i. for 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-sulfide or -10-thione:

Since then, a variety of derivatives based on the oxaphosphaphenanthrene ring system have been described for use as fire retardants in the patent literature.

Thus, Shinichi et al. in US 4,198,492 (to Asahi Dow) discloses the use of DOPO derivatives of the formula below as fire retardants in polyphenylene ether resins:

Wherein the symbols have the following meaning: Z is oxygen or sulfur; Q = 0 or 1; X is hydrogen, a hydroxyl group, an amino group, a halogen atom, O-i.-io-alkyl, Ci-io-alkoxy, Ci-io-alkylthio or optionally hydroxy-substituted C6-io-aryloxy; Yi and Y2 are C 1-8 -alkyl, C 1-8 -alkoxy or an aryl group; and n and p are integers from 0 to 4.

As specific examples of compounds with Z = sulfur, derivatives with X =H, alkoxy and aryloxy are mentioned, including explicitly also DOPS. However, as the sole sulfur-containing derivative, the following compound is mentioned:

However, this substance is not characterized in detail, but only incorporated into a resin mixture whose properties have been studied, among other things, an average result in the flame time measurement was achieved.

WO 2009/035881 by Dow Global Technologies describes flame retardant polymer compositions in which various phosphorus compounds are used as active ingredients. In this connection, the structure of a large number of compounds having four phosphorus-bonded heteroatoms, which are either oxygen or sulfur, i. More specifically, salts and esters of phosphoric acid and various thione and thione phosphoric acids, sometimes in polymeric form, are described.

Also included is the structure of dimers of DOPS in which two DOPS molecules are linked together via a sulfide or disulfide bridge instead of hydrogen (ie, "DOPS-S-DOPS" and "DOPS-S2", respectively). DOPS "), as well as analogs thereof in which the oxygen of dihydrooxaphosphaphenanthrene (DOP) is replaced by sulfur, ie Dihydrophospha-sulfaphenanthrene (DPS) derivatives (so-called " DPSS-S-DPSS " and " DPSS-S2-DPSS ", respectively).

In WO 2009/035881, however, not a single DOPO derivative was actually prepared and thus not uncharacterized or disclosed reusable, but exclusively non-aromatic compounds.

Also in the Austrian patent application AT AM 1044/09 advantageous sulfur-containing DOPO and DOPS derivatives have been proposed and made reworkable and found that these compounds, alone or in combination with each other or other sulfur-containing compounds, improved over the prior art Show flame retardancy.

Specifically, in AT AM 1044/09 new compounds of the following formulas I and II, synthetic method therefor and their use as flame retardants are disclosed:

Wherein: X is selected from hydrogen, OH and SH and alkali metal, alkaline earth metal, ammonium and phosphonium salts thereof; Υι, Υ2 and Ζ each independently represent an oxygen atom or a sulfur atom; With the proviso that in formula I at least one of X and Yi and in formula II at least one of Y-i, Y2 and Z represents a sulfur atom; N is an integer of at least 1, wherein when Z is an oxygen atom, n = 1, and when Z is a sulfur atom, n = 1 to 8; Each R independently represents an alkyl, alkoxy or alkylthio group having 1 to 8 carbon atoms or an aryl group; and each m is independently an integer of 0 to 4; as well as ring-opened hydrolysates of these compounds.

The improved flame retardant effect is attributed to increased gas phase activity of the new compounds.

In the following Austrian patent application AT AM 570/10 further new sulfur-containing DOPO and DOPS derivatives, namely four new ammonium salts of compounds of formula I and three new dimers of formula II, were first synthesized and disclosed.

The equipment of polymer foams with flame retardants is for a variety of applications of importance, for example, for polystyrene foam expanded polymer polystyrene (EPS) or polystyrene extrusion foam boards (XPS) for insulating buildings. Hitherto predominantly halogenated, in particular brominated, organic compounds such as hexabromocyclododecane (HBCD) have been used for polystyrene homopolymers and copolymers. However, a number of these brominated substances are in discussion or already banned because of their potential environmental and health hazards.

As an alternative, there are numerous halogen-free flame retardants. However, halogen-free flame retardants generally have to be used in significantly higher amounts in order to achieve the same flame retardancy of halogen-containing flame retardants.

For this reason, among other things, halogen-free flame retardants that can be used in compact thermoplastic polymers often can not be used equally in polymer foams because they either interfere with the foaming process or influence the mechanical and thermal properties of the polymer foam. In the production of expandable polystyrene by suspension polymerization, the high flame retardant can also reduce the stability of the suspension and thus interfere with the production process or affect.

The effect of flame retardants used in compact polymers in polymer foams is often unpredictable due to the peculiarities of such foams and the different fire behavior or because of different fire tests.

In this regard, WO 2006/027241 describes from the prior art halogen-free flame retardants for polymer foams which do not significantly affect the foaming process and the mechanical properties and also enable the production of predominantly closed-cell polymer foams. These flame retardants are known and commonly used since the early 1970s phosphorus compounds, for example, according to JP-A 2004-035495, JP-A 2002-069313 or JP-A 2001-115047 is to produce. Particularly preferred is the above-mentioned phosphorus oxide 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (6H-dibenz [c, e] -oxaphosphorin-6-oxide, DOP-O, CAS [35948 -25-5]).

Even with this flame retardant, however, relatively high concentrations of flame retardants are still required to arrive at a qualitatively corresponding product and these high concentrations affect the foam structure and the stability of the matrix relatively strong. In addition, the European fire class E tested according to EN 11925 or B1 tested according to DIN 4102 can not be met.

Furthermore, in the Austrian patent application AT 1058/2009 the use of the described in AT AM 1044/09, compounds of the above formulas I and II, as flame retardants in polymer foams and flame-retardant, at least one blowing agent containing, expandable polymers described ,

In WO2010 / 057851, melamine salts of DOPO, in particular melamine phenylphosphinate, flame-retardant styrene-containing polymer compositions and their preparation are described.

DE 1020080141117 describes amine derivatives of 6-amino- (6H) -dibenz (c, e) (1,2) -oxaphosphorine-6-sulfides.

The object of the present invention is to provide a halogen-free flame retardant, but qualitatively corresponding, expandable polymer containing a special flame retardant, which must be used only in small amounts or not the subsequent foaming process and the mechanical properties of the foam significantly influenced.

Furthermore, it is an object of the invention to provide an advantageous process for the preparation of such polymers.

Another object of the invention is to provide a halogen-free flame retardant, but qualitatively corresponding, polymer foam with advantageous fire behavior and good mechanical properties as well as an advantageous manufacturing method for it.

These objects are achieved by the characterizing features of the independent claims of the invention.

Continuing the research succeeded for the first time to synthesize new ammonium salts of compounds of formula I and new dimers of formula II and to use in expandable polymers or polymer foams and thus obtain advantageous polymers and polymer foams that were good flame retardant and easy to manufacture and have good mechanical properties.

Specifically, the present invention therefore relates in a first aspect, novel flame-retardant, propellant-containing, expandable or expandable or foamable polymers containing as flame retardants at least one phosphorus compound of the following general formula (I) or (II), or ring-opened hydrolysates thereof containing: 1) a compound of the above formula I in which X is sulfur and the sulfur on X is present as the ammonium salt of triethylamine (TEA, N (Et) 3), ie 9,10-Dihydro-10-mercapto-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt (" DOPS-SNH (Et) 3 ")

2) a compound of the above formula I in which X is oxygen and the oxygen on X is present as the ammonium salt of triethylamine (" TEA ", " N (Et) 3 "), i. 9,10-Dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt (" DOPS-ONH (Et) 3 ")

3) a compound of the above formula I, wherein X is oxygen, and the oxygen on X is present as the ammonium salt of guanidine (" Gua "), i. 9,10-Dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide-guanidinium salt (" DOPS-OGua ")

4) a compound of the above formula II, wherein n = 1 and no substituent R is present, i. E. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide (" DOPS-S-DOPS ")

5) a compound of the above formula II, wherein n = 2 and no substituent R is present, i. E. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) disulfide (" DOPS-S2-DOPS ")

6) a compound of the above formula II, wherein n = 4 and no substituent R is present, i. E. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) tetrasulfide (" DOPS-S4-DOPS ")

Since the cyclic thiophosphonic or -phosphinsäure esters of compounds of formula I or II is easily hydrolyzed by the skilled person under suitable conditions, are also "ring-opened hydrolysates". within the scope of the invention. These are therefore to be understood as compounds in which the following structure is contained:

Which structure may also be present in one or both of the monomeric units of dimers of Formula II above, such that such dimers are also included within the definition of " ring-opened hydrolysates " fall, since such hydrolysates may also be effective as flame retardants.

As mentioned in the introduction, although the structures DOPS-S-DOPS and DOPS-S2-DOPS are already formally described in WO 2009/035881, these compounds have not yet been synthesized or further characterized. This has only now been achieved, and it has only now been found that these particular compounds have improved flame retardancy and synergistic activity with elemental sulfur and other sulfur containing compounds over other related representatives of the disclosed linking groups.

As shown in the later embodiments, the above seven novel compounds have very good flame retardancy. With these flame retardants polymers and polymer foams with improved flame retardancy and improved properties could be created. In addition, even relatively small amounts are sufficient to achieve the same effect.

An advantageous embodiment of the invention is characterized in that it was surprisingly found that the new compounds in combination with elemental sulfur and other sulfur-containing compounds have synergistic effects as flame retardants.

In this way, obtainable expandable polymers are characterized in that the at least one flame retardant in combination with elemental sulfur and / or another sulfur-containing compound or sulfur compound is used, in particular in an amount of 0.1 to 10% by weight, in particular an amount of about 0.5 to 5% by weight, preferably about 2% by weight, based on the total weight of the polymer. It is particularly advantageous if this further sulfur-containing compound has at least one S-S bond, where at least one of the sulfur atoms is in divalent form.

As sulfur compounds, for example, sulfides, sulfites, sulfates, sulfanes, Sul-foxylates, sulfones, sulfonates, thiosulfates, thionites, thionates, disulfates, sulfoxides, sulfur nitrides, sulfur halides and / or organosulfur compounds such as thiols, thioethers, thiophenes, etc. are advantageous used.

Furthermore, sulfur compounds have proved advantageous in the analysis by means of thermogravimetry (TGA) below 115 ° C, a weight loss of less than 10 wt .-%, for example, ammonium thiosulfate, Dicaprolactamdisulfid, zinc sulfide, polyphenylene sulfide, etc ..

It is particularly advantageous if the sulfur-containing compound or sulfur compound has at least one S-S bond, wherein at least one of the sulfur atoms is in divalent form, e.g. Disulfites, dithionites, cystine, amylphenol disulfide, poly-tert-butylphenol disulfide, etc.

Comparative experiments clearly show that the novel compounds of the present invention when used in combination with elemental sulfur or sulfur-containing compounds with which they show synergistic activity, significantly better flame retardant effects than the known additive DOPO.

The halogen-free, flame-retarded polymer foams preferably comprise a thermoplastic polymer, in particular a styrene polymer.

The expandable polymers according to the invention are preferably expandable styrene polymers (EPS) or expandable styrene polymer granules (EPS). These are advantageously homo- and copolymers of styrene, preferably glass clear polystyrene (GPPS), impact polystyrene (HIPS), anionically polymerized polystyrene or impact polystyrene (A-IPS), styrene-alpha-methylstyrene copolymers, acrylonitrile-butadiene-styrene polymers (ABS). , Styrene-acrylonitrile (SAN) acrylonitrile-styrene-acrylic ester (ASA), methyl acrylate-butadiene-styrene (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) polymers or mixtures thereof or with polyphenylene ether (PPE). Especially for polystyrene, the need for high-quality products is particularly high.

The abovementioned styrene polymers may be used to improve the mechanical properties or the temperature resistance, if appropriate by using compatibilizers with thermoplastic polymers, such as polyamides (PA), polyolefins, such as polypropylene (PP) or polyethylene (PE), polyacrylates, such as polymethyl methacrylate (PMMA). , Polycarbonate (PC), polyesters, such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), polyethersulfones (PES), polyether ketones or polyether sulfides (PES) or mixtures thereof, generally in proportions of not more than 30% by weight, preferably Range of 1 to 10 wt .-%, based on the polymer melt, blended.

Furthermore, mixtures in the aforementioned quantitative ranges with z. B hydrophobically modified or functionalized polymers or oligomers, rubbers such as polyacrylates or polydienes, z. As styrene-butadiene block copolymers or biodegradable aliphatic or aliphatic / aromatic copolyesters possible.

Suitable compatibilizers are, for example, Maleic anhydride-modified styrene copolymers, polymers containing epoxy groups or organosilanes.

An advantageous embodiment of the expandable polymers is that the compounds either alone as a flame retardant additive, e.g. in plastic compositions, wherein they are preferably present in a proportion of 0.1 to 25 wt .-%, preferably 3 to 10 wt .-%, based on the total weight of the polymer, or as part of a flame retardant composition which In addition, it may comprise any other components usually contained in such compositions. These include, for example, organic peroxides, e.g. Dicumyl peroxide, metal hydroxides, nitrogen compounds, e.g. Melamines, nanoparticles, etc.

The effectiveness of the phosphorus compounds can be further improved by the addition of suitable flame retardant synergists, such as the thermal radical formers dicumyl peroxide, di-tert-butyl peroxide or dicumyl.

Also, in addition, other flame retardants, such as melamine, Melamincyanurate, metal oxides, metal hydroxides, phosphates, phosphinates or synergists such as Sb203 or Zn compounds can be used.

If it can be dispensed with the complete freedom from halogen of the polymer or the polymer foam, halogen reduced foams by the use of phosphorus compounds and the addition of lesser amounts of halogenated, in particular brominated flame retardants, such as hexabromocyclodecane (HBCD), preferably in amounts ranging from 0 , 05 to 1, in particular 0.1 to 0.5% by weight, are produced.

The halogen-free, flameproofed polymer foams preferably have a density in the range from 8 to 200 g / l, particularly preferably in the range from 10 to 50 g / l, and are preferably more than 80%, particularly preferably 95 to 100%. , closed-cell.

Another aspect of the invention relates to the preparation of such polymers. According to the invention, the flame-retardant, expandable polymers mentioned above can be prepared in a manner known per se by admixing the abovementioned flameproofing agents and, if appropriate, sulfur and / or at least one sulfur-containing compound or sulfur compound.

An advantageous process procedure provides that the flame retardant and a blowing agent are mixed with a styrene polymer melt with the aid of a dynamic or static mixer and then granulated.

Alternatively, it can be provided that the flame retardant is admixed by means of a dynamic or static mixer to still granular polystyrene polymer and melted and the melt is then impregnated and granulated.

Alternatively, it can further be provided that the flame retardant is admixed by means of a dynamic or static mixer to still granular EPS and the mixture is then melted and granulated.

Alternatively, it can further be provided that the granules are produced by suspension polymerization of styrene in aqueous suspension in the presence of the flame retardant and a propellant.

Sulfur and / or at least one sulfur-containing compound or sulfur compound is added simultaneously with the flame retardant.

A further process according to the invention for the preparation of the flame-retardant expandable styrene polymers (EPS) according to the invention comprises the steps: - Dosing together in an extruder of PS or EPS granules with a

Molecular weight of Mw > 120 000 g / mol, preferably from 150 000 to 250 000 g / mol, more preferably from 180 000 to 220 000 g / mol, and of the flame retardant and optionally one or more further additives, - melting all components together in the extruder - optional addition of at least one propellant

- Mix all components at a temperature > 120 ° C

Granulation by means of pressurized underwater granulation, e.g. 1-20 bar, to a granule size < 5 mm, preferably 0.2 to 2.5 mm, at a water temperature of 30 to 100 ° C, in particular 50 to 80 ° C, - optionally superficial coating with coating agents, e.g. Silicates, metal salts of fatty acids, fatty acid esters, fatty acid amides.

The halogen-free flame-retardant, expandable styrene polymers (EPS) and styrene polymer extrusion foams (XPS) according to the invention can be prepared by mixing in a blowing agent and a phosphorus compound of the general formula (I) or (II) or the hydrolysis product or a salt thereof, and optionally sulfur and / or or at least one sulfur-containing compound or sulfur compound, into which polymer melt and subsequent extrusion into foam boards, foam strands, or expandable granules are made.

Preferably, the expandable styrenic polymer has a molecular weight > 120,000, more preferably in the range of 180,000 to 220,000 g / mol. Due to the reduction in molecular weight by shear and / or temperature, the molecular weight of the expandable polystyrene is usually about 10,000 g / mol below the molecular weight of the polystyrene used.

The styrene polymer melt may also be blended with polymer recyclates of said thermoplastic polymers, in particular styrene polymers and expandable styrene polymers (EPS), in amounts which do not substantially impair their properties, generally in amounts not exceeding 50% by weight, in particular in amounts of 1 to 20 wt .-%.

The blowing agent-containing styrene polymer melt generally contains one or more blowing agents in a homogeneous distribution in a proportion of 2 to 10 wt .-%, preferably 3 to 7 wt .-%, based on the propellant-containing styrene polymer melt. Suitable blowing agents are the physical blowing agents commonly used in EPS, such as aliphatic hydrocarbons having 2 to 7 carbon atoms, alcohols, ketones, ethers or halogenated hydrocarbons. Preference is given to using isobutane, n-butane, isopentane, n-pentane. For XPS, preference is given to using CO 2 or mixtures with alcohols or ketones.

The added amount of blowing agent is chosen so that the expandable styrene polymers (EPS) have an expansion capacity of 7 to 200 g / l, preferably 10 to 50 g / l.

The expandable styrene polymer pellets (EPS) according to the invention generally have a bulk density of at most 700 g / l, preferably in the range from 590 to 660 g / l.

Further, the styrenic polymer melt may contain additives, nucleating agents, fillers, plasticizers, soluble and insoluble inorganic and / or organic dyes and pigments, e.g. IR absorbers such as carbon black, graphite or aluminum powder, shared or spatially separated, e.g. via mixers or side extruders. In general, the dyes and pigments are added in amounts ranging from 0.01 to 30, preferably in the range of 1 to 10 wt .-%, added. For homogeneous and microdispersed distribution of the pigments in the styrene polymer, it may be expedient, in particular in the case of polar pigments, to use a dispersing aid, for example organosilanes, polymers containing epoxy groups or styrene polymers grafted with maleic anhydride. Preferred plasticizers are mineral oils, phthalates, which can be used in amounts of from 0.05 to 10% by weight, based on the styrene polymer.

E in a further aspect of the invention relates to a polymer foam, in particular a styrene polymer foam or an extruded polystyrene foam (XPS), containing as flame retardant at least one phosphorus compound of general formula (I) or (II) or ring-opened hydrolysates or salts from that.

Advantageously, sulfur and / or at least one sulfur-containing compound or sulfur compound may additionally be present.

This polymer foam is obtainable from the inventive flame-retardant expandable polymers, in particular from expandable styrene polymers (EPS), in particular by foaming and mixing of the polymers or by extrusion.

A particularly advantageous polymer foam has a density between 7 and 200 g / l and has a predominantly closed-cell structure with more than 0.5 cells per mm3.

According to the invention, at least one of said phosphorus compounds of the general formula (I) or (II) or ring-opened hydrolyzates or salts thereof, as flame retardants in expandable polymers, in particular in expandable styrene polymers (EPS) or expandable styrene polymer granules (EPS) or in polymer foams, in particular in styrene polymer particle foams obtainable by foaming from expandable polymers, or in extruded polystyrene rigid foams (XPS).

For the production of flame-retardant extruded polystyrene rigid foam (XPS), the flame retardant and a blowing agent, and optionally sulfur and / or at least one sulfur-containing compound or sulfur compound are mixed with a styrene polymer melt by means of a dynamic or static mixer and then foamed or the flame retardant is admixed by means of a dynamic or static mixer to still granular polystyrene polymer and melted, and then the melt impregnated and foamed.

In order to ensure the reworkability of the polymers and foams of the invention, the following is stated: A) PREPARATION OF THE FLAME-PROTECTION AGENTS AND THEIR DERIVATIVES: The said flame-retardants and their derivatives can be prepared, for example, by reacting a 9,10-dihydro -9-oxa-10-phosphaphenanthrene (DOP) derivative selected from DOPS, DOPS-SH, DOPS-OH and DOPS-SNH (Et) 3 with elemental sulfur, a sulfur-containing compound or an amine to give the desired compound of the invention I or II is implemented.

By means of such syntheses, the new compounds can be obtained in very good yields and without appreciable formation of by-products such as hydrolysates or decomposition products. In addition, less complex purification steps are required because residues of the reactants used in the preparation, i. Remains of elemental sulfur or sulfur compounds that do not affect flame retardancy, but on the contrary even synergistically reinforce.

Particularly preferred reactions for obtaining the compounds of the invention are given below: The reaction of DOPS with sulfur and triethylamine to DOPS-SNH (Et) 3:

The reaction of DOPS-OH with triethylamine to give DOPS-ONH (Et) 3:

The reaction of DOPS-OH with melamine to DOPS-OMel:

The reaction of DOPS-OH with guanidine carbonate to DOPS-OGua:

Dimerization of DOPS-SH to DOPS-S-DOPS:

The reaction of DOPS-SNH (Et) 3 with hydrogen peroxide with simultaneous dimerization to DOPS-S2-DOPS:

The reaction of DOPS-SNH (Et) 3 with disulfur dichloride to DOPS-S4-DOPS:

Of course, these compounds can also be obtained in other ways, and one of ordinary skill in the art, taking into account the particular phosphorin chemistry, should be able to identify a number of alternative synthetic routes, both those already starting from a DOP derivative and those in which the Dihydrooxaphos-phaphenanthren basic body is yet to be formed, for example similar to that disclosed in DE 20 34 887 synthesis starting from o-phenylphenol.

In the following examples, preferred syntheses of the relevant starting materials and the novel compounds are described in detail. Unless otherwise specified, the DOP starting materials were prepared according to the Austrian patent application AT AM 1044/09. SYNTHESIS EXAMPLE 1 Preparation of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-thione and -10-sulfide (DOPS) from DOPO and phosphorus pentasulfide, respectively

Under inert gas purging 54 g (0.25 mol) DOPO were placed in a round bottom flask equipped with a thermometer, mechanical stirrer and reflux condenser, after which 150 ml of air and moisture-free toluene were added. After heating the mixture to 50-55 ° C, 27.8 g (0.0625 mol) of P2S5 were added with vigorous stirring. The temperature was allowed to drop to 45 ° C and maintained at this level with continued stirring. In the course of the reaction, the P2S5 became a viscous mass. After stirring for 12 h, an additional 10 g of P2S5 was added and stirring was continued for a further 5 h. Subsequently, the supernatant solution was decanted from the viscous dregs and the solvent removed in vacuo. To the oily distillation residue was added 100 ml of chloroform. A small amount of insoluble solid was filtered off. Thereafter, the filtrate was stirred for 15 min with exclusion of oxygen with 100 ml of 5% NaHCO 3 solution to remove traces of DOPO still contained. The milky cloudy chloroform phase was separated, washed with 100 ml of water, dried over anhydrous Na 2 SO 4 and filtered through diatomaceous earth. From the filtrate, the solvent was distilled off under reduced pressure to leave a viscous oil which gradually solidified to a solid which was about 94% DOPS and recrystallized from acetonitrile. This gave 41.8 g (72% of theory) of DOPS as a white, crystalline solid.

Mp: 92-94 ° C (acetonitrile) [00117] 31P-NMR (CDCl 3): 58.6 ppm [00118] MS: 232 (C12H9OPS) [00119] elemental analysis: calc. P 13.35%, gef. P 13.23% EXAMPLE 1 [00120] Preparation of 9,10-dihydro-10-mercapto-9-oxa-10-phosphaphenanthrene-10-thione; -10-sulfide triethylammonium salt (DOPS-SNH (Et) 3)

9.3 g (0.04 mol) of DOPS and 1.31 g (0.041 mol) of sulfur were dissolved in 100 ml of abs. Toluene for 1.5 h at 35 ° C stirred. Subsequently, 5.3 g (0.053 mol) of triethylamine were added dropwise with stirring and the suspension obtained for 1 h at about 50 ° C stirred. After allowing to cool to room temperature, the precipitated solid is filtered off, washed with diethyl ether and dried under gentle heating in vacuo. In this way, 13.4 g (92% of theory) of DOPS-SNH (Et) 3 were obtained as a white crystalline solid.

Mp: 137-139 ° C

31P-NMR (CDCIs): 99.8 ppm [00124] Elemental Analysis: calc. P 8.47%, m.p. P 8.32% EXAMPLE 2 Preparation of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -1O-sulfide triethylammonium salt (DOPS-ONH (Et) 3, respectively) )

To a suspension of 12.41 g (0.05 mol) DOPS-OH in 75 ml abs. Toluene was added dropwise at 60 ° C within 15 min 6 g (0.06 mol) of triethylamine with stirring. The reaction mixture was stirred for a further 30 minutes and then cooled. The precipitated solid was filtered through a glass frit, washed with ether and dried with gentle Ewär-men in vacuo. In this way, 13.4 g (99% of theory) of DOPS-OH (Et) 3 were obtained as a white crystalline solid.

Mp: 147-148.5 ° C

31P-NMR (CDCl 3): 61.3 ppm [00129] Elemental Analysis: calc. P 8.86%, m.p. P 8.78% EXAMPLE 3 [00130] Preparation of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide melamine salt (DOPS-OMel)

Under an inert gas purge, 126.1 g (1.0 mol) of finely ground melamine in 1300 ml of water at room temperature were placed in a round bottom flask equipped with a mechanical stirrer and a reflux condenser. To this suspension was added with vigorous stirring 248.2 g (1.0 mol) of DOPS-OH. The reaction mixture was heated to 90 ° C and stirred for a further 4 h at the same temperature. The stirrable slurry formed upon cooling to room temperature was filtered and the filter cake was heated to a residual moisture? 0.1% (Karl Fischer) at 70 ° C in the air and then ground, whereby 365.7 g (98% of theory) of DOPS-OMel were obtained as a finely crystalline, white solid.

Mp: 275 ° C (dec.) (H 2 O) 31P-NMR (MeOH-d 4): 60.7 ppm Elemental analysis: calc. P 8.27%, N 22.44% , gef. P, 8.19%, N, 22.42. EXAMPLE 4 Preparation of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -1O-sulfide-guanidinium salt (DOPS-) OGua)

Under inert gas purge 90.1 g (0.5 mol) of guanidine carbonate were dissolved in 300 g of water at 60 ° C in a round bottom flask equipped with a mechanical stirrer and a reflux condenser. With vigorous stirring, 248.2 g (1.0 mol) of DOPS-OH were added in portions to this solution while avoiding excessive gas evolution. The suspension obtained was first heated at normal pressure to 140 ° C and after the evolution of steam in a water jet vacuum to 185 ° C to remove the water. After pouring out, cooling and grinding the formed anhydrous melt 304.5 g (99% of theory) of DOPS OGua were obtained as an amber powder.

Mp: 173-179 ° C (H 2 O) 31P-NMR (acetone-d 6): 57.9 ppm [00139] Elemental analysis: calc. P 10.07%, N 13.67%, m.p. , P 10.27%, N 13.69 EXAMPLE 5 Preparation of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide (DOPS-S-DOPS)

13.21 g (0.05 mol) of DOPS-SH were stirred in 120 ml of acetonitrile for 2 h under reflux and inert gas atmosphere to form a granular Fetsstoff which was filtered off and then stirred for 1 h in xylene under reflux , Thereafter, the solid was filtered off, washed with warm chloroform and then with diethyl ether and then dried in vacuo. Thus, 7.7 g (78% of theory) of DOPS-S-DOPS were obtained as a white crystalline solid.

M.p .: 237-239 ° C (xylene) 31P-NMR (CDCIs): 74.1 ppm; 74.8 ppm [00144] MS: 494 (Cz ^ eOzPzSs) Elemental analysis: calc. P 12.53%, m.p. P, 12.41% EXAMPLE 6 Preparation of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) disul-fide (DOPS-S2-DOPS)

To a suspension of 5.48 g (0.015 mol) DOPS-ONH (Et) 3 in 50 ml abs. Toluene was added at about 20 ° C by means of a syringe 0.66 g (0.018 mol) of 37% hydrochloric acid, after which 5.6 g (0.016 mol) of a 10% solution of hydrogen peroxide in ethyl acetate was added dropwise within 10 min with vigorous stirring were. After a further 30 minutes, 0.75 ml of triethylamine was added to neutralize excess hydrochloric acid, after which the volatiles were distilled off in vacuo. The residue was stirred with a mixture of 75 ml of water and 25 ml of ethanol for about 15 minutes with gentle heating to dissolve triethylamine hydrochloride. The solid was then filtered off with suction and stirred once more in water / ethanol. The white powder obtained after re-aspirating and drying with gentle heating in vacuo was recrystallized from acetonitrile to give 3.20 g (81% of theory) of DOPS-S2-DOPS.

M.p .: 126-130 ° C (dec.) (Acetonitrile) 31P-NMR (CDCl 3): 84.28 ppm; 84.65 ppm [00150] MS: 526 (Cz ^ eOzPzS ^ Elemental Analysis: Calcd. P 11.76%, Found P 11.62% EXAMPLE 7 Preparation of bis (9,10-dihydroxy) 9-oxa-10-phospha-10-thioxophenanthren-10-yl) tetra-sulphide (DOPS-S4-DOPS)

To a suspension of 2.75 g (0.0075 mol) of DOPS-ONH (Et) 3 in 50 ml of abs. Toluene was added at about 20 ° C using a syringe 0.51 g (0.00375 mol) Dischwefeldichlorid within 5 min. After completion of the addition, the reaction mixture was stirred for 2 hours at room temperature, after which the volatiles were distilled off in vacuo. The residue was stirred with a mixture of 50 ml of water and 10 ml of ethanol at 35 ° C for about 30 minutes to dissolve triethylamine hydrochloride. The solid was then filtered off with suction and stirred once more in a mixture of 30 ml of water and 20 ml of ethanol. After filtering off, the solid was recrystallized from acetonitrile and then dried under gentle heating in vacuo to give 1.9 g (86% of theory) of DOPS-S4-DOPS as a white solid.

From about 150 ° C (dec.) (Acetonitrile) [00155] 31P-NMR (CDCl 3): 84.0 ppm; 84.5 ppm [00156] MS: 590 (C24H1602P2S6) Elemental Analysis: calc. P 10.49%, m.p. P 10.56% B) PREPARATION OF EXPANDABLE POLYMERIZES WITH SUCH FLAME PROTECTION AGENTS: It should be noted in principle that the preparation of flame-retardant expandable polymers, e.g. of EPS, in the form of granules or beads, has long been known in the art and the preparation of the polymers according to the invention with the above flame retardants essentially works analogously. Thus, for example, the embodiments of WO 2006/027241 can be used, wherein instead of the phosphorus compounds used there, the flame retardants mentioned in the present invention are used. The same applies to the polymer foams or XPS.

In addition, attention is drawn to the contents of AT 1044/09, AT 570/210 and AT 1058/2009 and the methods disclosed therein for the preparation of the relevant substances or polymers are included in the content of the present application.

Thus, the skilled person is able to produce the desired flame retardants as such, as well as any required for the preparation of starting materials, as well as the polymers and polymer foams of the invention. CONCRETE EMBODIMENTS: The present invention will now be described in detail, by way of example, with reference to specific embodiments, which are not intended to be limiting. COMPARATIVE EXAMPLES (SEE ALSO TABLE 3): EXAMPLE 1 (COMPARATIVE EXAMPLE - 10% DOPO): A styrene polymer (SUNPOR EPS-STD: 6 wt% pentane, chain length MW = 200,000 g / mol, nonuniformity MW / Mn = 2.5 ) Was in the catchment area of a twin-screw extruder 10% by weight 9,10-dihydro-9-oxa-10-phospha-phenanthren-10 oxide (DOPO), based on the resulting EPS granules, mixed and melted in the extruder at 190 ° C. The polymer melt thus contained was conveyed through a nozzle plate at a rate of 20 kg / h and granulated with a pressurized underwater granulator to form compact EPS granules. EXAMPLE 2 (COMPARATIVE EXAMPLE -15% DOPO) Example 1 was repeated with the difference that 15% by weight of 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOPO), based on the resulting EPS granules were added. EXAMPLE 3 (COMPARATIVE EXAMPLE - 5% SULFUR): Example 1 was repeated with the difference that only 5% by weight of yellow sulfur, based on the resulting EPS granules, was added. EMBODIMENTS: EXAMPLE 4 (EMBODIMENT-10% DOPS-SNH (ET) 3): A styrene polymer (SUNPOR EPS-STD: 6% by weight of pentane, chain length MW = 200,000 g / mol, nonuniformity Mw / Mn = 2.5 ) was in the catchment area of a twin-screw extruder 10 wt% 9,10-dihydro-10-mercapto-9-oxa-10-phosphaphenanthren-10-thione or. 10-sulfide triethylammonium salt (DOPS-SNH (Et) 3), based on the resulting EPS granules, mixed and melted in the extruder at 190 ° C. The polymer melt thus contained was conveyed through a nozzle plate at a rate of 20 kg / h and granulated with a pressurized underwater granulator to form compact EPS granules.

The following examples were carried out analogously or under the same conditions to Examples 1 to 4, but with different flame retardants or synergists. The data in% by weight are in each case based on the EPS granules obtained: Example 5 (exemplary embodiment - 10% DOPS-SNH (Et) 3 + 2% sulfur): [00168] 10% by weight 9,10-dihydro- 10-mercapto-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt (DOPS-SNH (Et) 3) and 2% by weight of yellow sulfur EXAMPLE 6 (EMBODIMENT -10% DOPS-ONH ( ET) 3): 10% by weight of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide triethylammonium salt (DOPS-ONH (Et) 3) EXAMPLE 7 (EMBODIMENT - 10% DOPS-ONH (ET) 3 + 2% SULFUR): 10% by weight of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or 10-sulfide triethylammonium salt (DOPS-ONH (Et) 3) and 2 wt% yellow sulfur EXAMPLE 8 (EMBODIMENT - 7.5% DOPS-OMEL + 2% SULFUR): 7.5% by weight 9,10 Dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or 10-sulfide melamine salt (DOPS-OMel) and 2 wt% yellow sulfur EXAMPLE 9 (EMBODIMENT-7.5% DOPS-OMEL + 5% BB DS): 7.5% by weight of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide melaminium salt (DOPS-OMel) and 5% by weight Bis (benzothiazolyl) disulfide (BBDS) EXAMPLE 10 (EMBODIMENT - 7.5% DOPS OGUA + 2% SULFUR): [00173] 7.5% by weight 9,10-dihydro-10-hydroxy-9-oxa-10 phosphaphenanthrene-10-thione or -10-sulfide-guanidinium salt (DOPS-OGua) and 2% by weight of yellow sulfur EXAMPLE 11 (EMBODIMENT - 7.5% DOPS-OGUA + 5% BBDS); 7.5% by weight of 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide-guanidinium salt (DOPS-OGua) and 5% by weight of bis (benzothiazolyl EXAMPLE 12 (EMBODIMENT - 7.5% DOPS S-DOPS + 2% SULFUR): [00175] 7.5% by weight of bis (9,10-dihydro-9-oxa-10-phosphate) 10-thioxophenanthren-10-yl) sulfide (DOPS-S-DOPS) and 2% by weight yellow sulfur EXAMPLE 13 (EMBODIMENT - 7.5% DOPS S-DOPS + 5% DCDS): 7.5% by weight Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide (DOPS-S-DOPS) and 5% by weight of Ν, Ν'-dicaprolactam disulfide (DCDS). EXAMPLE 14 (EMBODIMENT - 7.5% DOPS-S-DOPS + 5% BBDS): 7.5% by weight of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide (DOPS-S-DOPS) and 5 wt% bis (benzothiazolyl) disulfide (BBDS) EXAMPLE 15 (EMBODIMENT -10% DOPS-S2-DOPS): 10 wt% bis (9,10-dihydro-9-oxa -10-phospha-10-thioxophenanthren-10-yl) disulfide (DOPS-S2-DOPS) EXAMPLE 16 (EMBODIMENT -10% DOPS-S2- DOPS + 2% sulfur): 10% by weight of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) disulfide (DOPS-S2-DOPS) and 2% by weight of yellow Sulfur EXAMPLE 17 (EMBODIMENT -10% DOPS-S4-DOPS): [00180] 10% by weight of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) tetrasulfide (DOPS-S4 EXAMPLE 18 (EMBODIMENT -10% DOPS-S4-DOPS + 2% SWEAT): 10% by weight of bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl tetrasulfide (DOPS-S4-DOPS) and 2% by weight of yellow sulfur COMPARATIVE EXPERIMENTS - EVIDENCE OF EFFICACY: a) Efficiency in compact polystyrene: Even in compact polystyrene, advantageous effects of the above-mentioned flame retardants were found: [00183] Of polystyrene granules (Mw: about 192,000 g / mol, Tg: about 94 ° C) specimens were molded as follows. The granules were ground to a powder and mixed in a mortar with the respective additives. 12 g each of these solid mixtures were weighed into aluminum crucibles, which were then placed in a preheated oven and left at the required temperature in each case until the powder had melted into compact plates. The temperature required for this depends on the composition of the particular mixture and was between 165 and 195 ° C. in the test specimens examined, and the melting process was complete after 10 to 20 minutes, as indicated in the table below. After cooling, the plates were removed from the aluminum crucibles and sawed into test pieces for flame retardancy testing.

In order to investigate the afterburning time (in seconds) during flame treatment specimens of 70 × 13 × 4 mm were produced according to UL94. Shorter burn time values therefore represent a better fire protection effect.

UL94 is the test specification of Underwriters Laboratories, which has been incorporated into IEC / DIN EN 60695-11-10 and -20 with the same content. Ignition flames with a power of 50 W act twice briefly on the sample body, whereby in the vertical test the burning time and the falling off of burning parts are evaluated by means of a cotton swab arranged below the sample body. The classification takes place in the stages " VO ", " V1 " and " V2 ", which are explained in Table 1 below. The classification " VO " therefore represents the highest requirement for fire protection.

Table 1: UL94 classification

The fire test results obtained for the specimens are shown in Table 2 below and represent averages of four measurements each.

Table 2: Fire resistance tests according to UL94 for compact polystyrene

DCDS: Ν, Ν'-dicaprolactam disulfide BBDS: Bis (benzothiazolyl) disulfide The above results clearly demonstrate that the above compounds show, in the case of compact polymers, sometimes significantly better flame retardancy than the known additive DOPO. In particular, this is the case with combined use with elemental sulfur or sulfur-containing compounds with which they exhibit synergistic activity. In addition, the incorporation of the compounds of the invention into a resin composition is in most cases facilitated with respect to DOPO.

In addition, however, the above table also clearly shows that the synergism of these compounds is substance specific, i. E. Not every sulfur-containing compound known as flame retardant acts synergistically to the same extent, if at all. For example, the melamine or guanidinium salt of DOPS (Experiments 12-15) with sulfur provides significantly better results than BBDS, although BBDS when used alone has better flame retardancy than the same amount by weight of sulfur. This specificity of synergism is also evidenced by Experiments 16 to 18, in which the dimer DOPS-S-DOPS gives excellent results with sulfur and BBDS as synergists, while with DCDS one, in general, average, compared to the other compositions of the Invention rather poor performance is achieved.

The attempt to explain the sometimes excellent results of the dimer DOPS-S-DOPS by the presence of twice the molar amount of phosphorus and even three times the amount of sulfur at equal proportions by weight, is tested by experiments 19 to 22 with DOPS-S2 -DOPS and DOPS-S4-DOPS refuted. Although more sulfur is present in the same amount by weight of these compounds, the burning time values even deteriorate.

In summary, the above experiments clearly demonstrate the suitability of these DOPS derivatives as flame retardants, alone or in combination with another synergistic additive, this synergism being identified herein as substance-specific. b) Efficacy in the case of Expandable Polymers or Polymeric Foams: [0091] The flame-retardant expandable blowing agent-containing polymers according to the invention and also the polymer foams which can be produced therefrom and for which, as already mentioned, particular problems and requirements exist, show a clear result that the Advantages of the abovementioned flame retardants, which are present in many respects, are confirmed: Table 3 below presents the results in a concise manner, the fire behavior of defined test specimens being checked.

TABLE 3 Examination of the expandable polymers or of the polymer foams

With respect to polystyrene The results designated with tests 1 to 18 and recorded in the left-hand column were obtained by tests with products or test specimens based on the above-described comparison and working examples 1 to 18.

Experiments 1, 2 and 3 are references which correspond to a flame-retardant polymer or foam containing only the known flame retardant DOPO or containing only the synergist sulfur.

[00198] in detail: FIRE TEST IN ACCORDANCE WITH EN 11925 (COLUMN 6 IN TAB 3) AND DIN 4102 (COLUMN 7 IN TAB 3): The EPS granules obtained from Examples 1 to 18 became saturated foam with saturated water vapor prefoamed at a bulk density of 15 to 25 kg / m3, stored for 24 hours and formed in a molding machine to foam plates.

Test specimens with a thickness of 2 cm were cut from the foam boards and subjected to the fire tests according to EN 11925 and DIN 4102 after 72 hours of conditioning at 70 ° C. "Passed" were those tests which according to EN 11925 reached the European fire class E or according to DIN 4102 the fire class B2.

It can be seen that in the systems under consideration the fire class E according to EN 11925 could be achieved rather than the fire class B2 according to DIN 4102.

The results of experiments 4 to 18 show that all considered DOPS derivatives show better results or already in smaller amounts than the known flame retardant DOPO (experiments 1 and 2).

In order to achieve the fire class E according to EN 11925, in DOPS-SNH (Et) 3 (experiment 4) and DOPS-ONH (Et) 3 (experiment 6) only 2/3 of the amount of DOPO used (experiment 2) necessary. By using 2% by weight of sulfur, the fire class B2 according to DIN 4102 can be achieved with these DOPS derivatives (experiments 5 and 7).

The synergistic effect of 2% by weight of sulfur is also evident in DOPS-OMel (experiment 8), DOPS-OGua (experiment 10) and DOPS-S-DOPS (experiment 12). Lower synergistic effects of these derivatives were found to be 5% by weight of BBDS (Runs 9 and 11) and 5% by weight of DCDS (Run 13), while 5% by weight BBDS in combination with 7.5% DOPS-S-DOPS (Run 14) sufficient to reach the fire class B2.

A special position takes DOPS-S2-DOPS, which meets the requirements of fire classes B2 and E at a concentration of 10% by weight, while the combination of 7.5 wt% DOPS-S2-DOPS and 2 wt% sulfur the Requirements of class B2 not reached.

The fire protection systems of experiments 17 (10% by weight of DOPS-S4-DOPS) and 18 (7.5% by weight of DOPS-S4-DOPS + 2% by weight sulfur) meet the requirements of fire class E according to EN 11925, but not those Class B2 according to Din 4102.

Overall, the polymers and foams according to the invention are thus more advantageous than polymers or foams finished with DOPO as fire-retardant.

Claims (14)

Flame-retardant, at least one blowing agent-containing, expandable polymers in which at least one phosphorus compound of the following general formula (I) or (II) or ring-opened hydrolysates thereof is contained as flame retardant: wherein: X is selected from hydrogen, OH and SH and alkali metal, alkaline earth metal, ammonium and phosphonium salts thereof; Y-i, Y2 and Z each represent a sulfur atom; n is an integer of at least 1, wherein when Z is a sulfur atom, n = 1 to 8; each R independently represents an alkyl, alkoxy or alkylthio group having 1 to 8 carbon atoms or an aryl group; and each m is independently an integer from 0 to 4, characterized in that a) X in formula I is sulfur and the sulfur on X is present as the ammonium salt of triethylamine (TEA, N (Et) 3), i. 9,10-Dihydro-10-mercapto-9-oxa-10-phosphaphenanthrene-10-thione or -10-sulfide-triethylammonium salt (" DOPS-SNH (Et) 3 "): DOPS-SNH (Et) 3; or b) X in formula I is oxygen and the oxygen is present on X as the ammonium salt of triethylamine (" TEA ", " N (Et) 3 "), i. 9,10-Dihydro-10-hydroxy-9-oxa-10-phospha-phenanthrene-10-thione or -10-sulfide triethylammonium salt ("DOPS-ONH (Et) 3"): DOPS-ONH (Et),; or c) X in formula I is oxygen and the oxygen on X is present as an ammonium salt of guanidine ("Gua"), i. 9,10-dihydro-10-hydroxy-9-oxa-10-phosphaphenanthrene-10-thione respectively. 10-sulfide-guanidinium salt (" DOPS-OGua "): DOPS-OGua,; or d) n = 1 and no substituent R is present, i. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) sulfide (" DOPS-S-DOPS "): DOPS-S-DOPS; or e) n = 2 and no substituent R is present, i. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) disulfide (" DOPS-S2-DOPS "): DOPS-S2-DOPS; or f) n = 4 and no substituent R is present, i. Bis (9,10-dihydro-9-oxa-10-phospha-10-thioxophenanthren-10-yl) tetrasulfide (" DOPS-S4-DOPS "): DOPS-S 4-DOPS 2. Expandable polymers according to claim 1, characterized in that the expandable polymers are expandable styrene polymers (EPS) or expandable styrene polymer granules (EPS), which in particular of homo- and copolymers of styrene, preferably glass clear polystyrene (GPPS), impact polystyrene (HIPS ), anionically polymerized polystyrene or toughened polystyrene (A-IPS), styrene-alpha-methylstyrene copolymers, acrylonitrile-butadiene-styrene polymers (ABS), styrene-acrylonitrile (SAN) acryl-1-yr-styrene-acrylic esters ( ASA), methyl acrylate-butadiene-styrene (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) polymers or mixtures thereof or with polyphenylene ether (PPE). 3. Expandable polymers according to claim 1 or 2, characterized in that the / the flame retardant in an amount of 0.1 to 25 wt .-%, in particular 3 to 10 wt .-%, based on the total weight of the polymer, is included /are. 4. Expandable polymers according to one of the preceding claims, characterized in that additionally elemental sulfur, in particular yellow sulfur (Sb), and / or at least one further inorganic or organic sulfur-containing compounds or sulfur compound is contained, in particular in an amount of 0.1 to 10% by weight, in particular in an amount of about 0.5 to 5% by weight, preferably about 2% by weight, based on the total weight of the polymer. 5. Expandable polymers according to claim 4, characterized in that the further sulfur-containing compound or sulfur compound has at least one S-S bond, wherein at least one of the sulfur atoms is in divalent form. 6. A process for the preparation of flame-retardant, expandable polymers according to any one of claims 1 to 5, characterized in that as flame retardants at least one phosphorus compound of the general formula (I) or (II) according to claim 1, or ring-opened hydrolysates or salts thereof used and optionally as an additional flame retardant or synergist sulfur and / or at least one sulfur-containing compound or sulfur compound according to one of claims 4 or 5. 7. A process for the preparation of flame-retardant expandable styrene polymers (EPS) according to claim 6, wherein the flame retardant and a blowing agent and optionally the sulfur or sulfur compound mixed with a styrene polymer melt by means of a dynamic or static mixer and then granulated or - the flame retardant and optionally the sulfur or the sulfur compound is added by means of a dynamic or static mixer to still granular polystyrene polymer and melted, and then the melt is impregnated and granulated or - wherein the flame retardant and optionally the sulfur or the sulfur compound by means of a dynamic or static mixer to still granular EPS or mixed, and then the mixture is melted and granulated or - the granule preparation by suspension polymerization of styrene in wäs suspension in the presence of the flame retardant and a propellant and optionally the sulfur or the sulfur compound. A process for the preparation of flame-retardant expandable styrene polymers (EPS) according to claim 6 comprising the steps of: - dosing together in an extruder of PS or EPS granules having a molecular weight of Mw > 120 000 g / mol, preferably from 150 000 to 250 000 g / mol, particularly preferably from 180 000 to 220 000 g / mol, and of the at least one flame retardant and optionally one or more further additives, in particular a) Flammschutzsynergisten in one Concentration of 0.1 to 20% by weight, b) infrared opacifiers in a concentration of 0.1 to 1% by weight, c) stabilizers in a concentration of 0.1 to 1% by weight, d) further halogenated or halogen-free flame retardants in one concentration from 0.1 to 20% by weight and / or e) fillers in a concentration of 1 to 20% by weight - common melting of all components in the extruder, - optional addition of at least one blowing agent, - mixing of all components at a temperature > 120 ° C, granulation by means of pressurized underwater granulation, at e.g. 1-20 bar, to a granule size < 5 mm, preferably 0.2 to 2.5 mm, at a water temperature of 30 to 100 ° C, in particular 50 to 80 ° C, - optionally superficial coating with coating agents, e.g. Silicates, metal salts of fatty acids, fatty acid esters, fatty acid amides. 9. flame-retardant, expandable styrene polymers (EPS) obtainable by a process according to any one of claims 6 to 8. 10. Polymer foam, in particular styrene polymer particle foam or extruded polystyrene rigid foam (XPS), containing as flame retardant at least one phosphorus compound of the general formula (I) or (II) according to claim 1, or ring-opened hydrolysates or salts thereof. 11. Polymer foam according to claim 10, characterized in that sulfur and / or at least one sulfur-containing compound or sulfur compound according to one of claims 4 or 5 is contained as an additional flame retardant or synergist. 12. Polymer foam according to claim 10 or 11, obtainable from flame-retardant expandable polymers according to one of claims 1 to 5, in particular from expandable styrene polymers (EPS), in particular by foaming and sintering of the polymers or by extrusion. 13. A polymer foam according to any one of claims 10 to 12, having a density between 7 and 200 g / l and a predominantly closed-cell cell structure with more than 0.5 cells per mm3. 14. Use of at least one phosphorus compound of the general formula (I) or (II) according to claim 1, or of ring-opened hydrolyzates or salts thereof, as flame retardants, and optionally of sulfur and / or at least one sulfur-containing compound or sulfur compound according to one of claims 4 or 5 as a flame retardant or -Synergisten, - in expandable polymers, especially in expandable styrene polymers (EPS) or expandable styrene polymer granules (EPS) according to claim 2 or 3, or - in polymer foams, in particular in styrene polymer particle foams, obtainable by foaming from expandable polymers, or in extruded polystyrene rigid foams (XPS). No drawings for this