WO2011039292A1

WO2011039292A1 - Method for producing functionalized expandable graphite intercalation compounds

Info

Publication number: WO2011039292A1
Application number: PCT/EP2010/064518
Authority: WO
Inventors: Bastian Ewald; Hartmut Hibst; Alejandra Garcia Marcos; Robert Bayer; Steffen OEHLENSCHLÄGER
Original assignee: Basf Se
Priority date: 2009-10-01
Filing date: 2010-09-30
Publication date: 2011-04-07

Abstract

The invention relates to a method for producing functionalized expandable graphite intercalation compounds which comprise expandable graphite and at least one phosphorous flameproofing compound and which are characterized in that the at least one phosphorous flameproofing compound is embedded or intercalated in the expandable graphite.

Description

Process for the preparation of functionalized expandable graphite intercalation compounds

description

The invention relates to processes for producing functionalized expandable graphite intercalation compounds comprising an expandable graphite and at least one phosphorus-containing flame retardant compound. Expandable graphite, which is also referred to as expandable graphite, as a flame retardant, for example, in polystyrene ("PS") or in impact modified polystyrene ("HIPS"), is known for example from WO 03/046071 A1. In addition, according to this document as a further flame retardant component, a halogen-containing compound in amounts of 2 to 1 1%, calculated as halogen needed. For toxicological reasons, however, it is desirable to avoid the use of halogenated flame retardants as much as possible.

Halogen-free flame-retardant styrene polymers containing expandable graphite and a phosphorus compound as flame retardant component are described in WO 00/34367 A2 and WO 00/34342 A2. However, molding compositions based on such type of flame-retardant styrene polymers are in need of improvement in terms of their dripping behavior in the event of fire.

WO 2005/103136 A2 discloses flame-retardant styrenic polymers which contain, in addition to expandable graphite and a phosphorus compound, a further co-additive intended to suppress the migration of the phosphorus-containing flame retardant to the polymer surface. As such a co-additive, for example, polycarbonate is called.

KR 1996-0001006 discloses flame-retarded polystyrene wherein the flame retardant components include expandable graphite, a phosphorus compound and Teflon. The mean particle size of the expandable graphite is 5 μm. The teflon added as an anti-dripping agent is used in amounts of from 1 to 5% by weight. The halogen-free flame-retardant molding compositions thus obtained have good heat resistance and impact resistance.

It is often difficult to achieve sufficient flame retardancy in the case of thermoplastic molding compositions which are flame-retardant with expandable graphite, on the one hand, but nevertheless to maintain sufficiently good mechanical properties of the thermoplastic molding composition. The object of the present invention was therefore to provide a process for the preparation of flame retardants based on expanded graphite.

According to a first embodiment of the invention, a method for producing a functionalized expandable graphite intercalation compound is included

(a) providing graphite,

(B) reacting the graphite with at least one oxidizing agent in the presence of at least one phosphorus-containing flame retardant compound with intimate mixing, provided by means of which functionalized expandable graphite intercalation compounds can be prepared. In the context of the process according to the invention, the graphite particles or the graphite with the oxidizing agent, which is preferably selected from the group of concentrated hydrochloric acid, nitric acid (HN0 ₃ ), KCI0 ₄ , H ₃ P0 ₄ , KMn0 ₄ , hydrogen peroxide, sulfuric acid and peroxosulfuric in Presence of at least one phosphorus-containing flame retardant compound implemented.

The reaction in process step (b) is generally carried out under an inert or inert gas atmosphere, for example under an argon or nitrogen atmosphere, at a temperature in the range from 0 to 120 ° C., preferably at about 30 ° C., over a period of 1 to 10 hours ,

In general, the process is carried out with intimate mixing of the components, the graphite, the oxidizing agent and the at least one phosphorus-containing flame retardant compound in process step (b) in a kneader, mixer or stirred tank. Process step (b) can be carried out both continuously and discontinuously. In continuous operation, for example, two or more of the above-mentioned apparatuses are operated alternately, whereas in discontinuous operation at least one apparatus is operated in batches.

The ratio of oxidizing agent to phosphorus-containing flame retardant compound is generally in the range of 1: 0.05 to 1: 5 parts by weight, preferably 1: 0.1 to 1: 4. The mixture of oxidizing agent and phosphorus-containing flame retardant compound is used in an amount of 1 to 200 parts by weight , preferably 50 to 150 parts by weight, based on 10 parts by weight of graphite used. Using the method described above, starting from graphite and using an oxidizing agent, functionalized expandable graphite intercalation compounds are obtained, which are outstandingly suitable as a flame retardant component for plastics.

According to a second embodiment of the invention, there is provided a process for producing functionalized expandable graphite intercalation compounds, comprising (e) providing expandable graphite (expanded graphite),

(F) reacting the expandable graphite with at least one phosphorus-containing flame retardant compound with intimate mixing of the expandable graphite with the at least one phosphorus-containing flameproofing compound.

In accordance with this embodiment of the invention, a second process for producing the above-described functionalized expandable graphite intercalation compound is provided, in the context of which expandable graphite with the at least one phosphorus-containing flame retardant compound is intimately mixed with the at least two components of expandable graphite and the at least one phosphorus-containing flame retardant compound , is implemented.

The preparation is preferably carried out under an atmosphere of air or inert gas, more preferably under argon or nitrogen atmosphere at a temperature in the range of 0 to 350 ° C, preferably in the range of 10 to 200 ° C, more preferably in the range of 80 to 150 ° C. , more preferably in the range of 50 to 120 ° C over a period of 1 minute to 24 hours, preferably over a period of 0.5 to 3 hours. The preparation is generally carried out at a pressure in the range from 0.1 bar to 20 kbar, preferably at 0.5 to 2.5 bar, particularly preferably at ambient pressure.

In general, the process is carried out with intimate mixing of the components, the expandable graphite and the at least one phosphorus-containing flame retardant compound in process step (f) in a kneader, mixer or stirred tank. Process step (f) can be carried out both continuously and discontinuously. In continuous operation, for example, two or more of the above-mentioned apparatuses are operated alternately, whereas in discontinuous operation, an apparatus is operated in batches. According to this embodiment of the invention, the ratio of the at least one phosphorus-containing flame retardant compound to the expandable graphite varies depending on the preparation. In general, the ratio of expandable graphite to the at least one phosphorus-containing flame retardant compound is in the range from 1:20 to 20: 1. If process step (f) is carried out in a kneader, the weight ratio of flame retardant compound to expandable graphite is 0.1 to 1 to 1, preferably 0.2 to 1 to 1, particularly preferably 0.5 to 1. If process step (f) is carried out in a stirred tank, the weight ratio of flameproofing compound to expandable graphite is 1: 1 to 10: 1, preferably 1: 1 to 5: 1, more preferably 1: 2.5 to 1: 3.5. The method is particularly suitable for incorporating solid, liquid or gaseous phosphorus-containing flameproofing compounds into expandable graphite.

After the production of the functionalized expandable graphite intercalation compounds according to the invention, ie following process step (b) or (f), a subsequent filtration of the mixtures obtained in step (b) or (f) or obtained functionalized expandable graphite intercalation compounds can be carried out if necessary become. The filtration step serves to separate excess flame retardant compounds from the expandable graphite intercalation compounds, or possibly also the removal of excess oxidant. The filtration or the filtration step (g) can be carried out continuously, for example with a belt filter or a centrifuge or discontinuously with a suction filter or a filter press. The flame retardant compound separated off in process step (g) can then be supplied in process step (b) or (f). In general, the filtration is carried out in process step (g) in at least one belt filter, a centrifuge, a suction filter or a filter press.

According to one embodiment of the invention, the (g) functionalized expandable graphite intercalation compounds obtained in process step (b) or (f) are dried in a further process step (h) in order to separate off excess flame retardant and, for example, to obtain a free-flowing powder. The drying, which in the present case is a thermal aftertreatment, also serves to reduce possible volume changes of the functionalized expandable graphite intercalation compound during incorporation into polymers. The drying can be carried out in a fluidized bed dryer, a paste mill dryer, a thin-film dryer, a current dryer Belt dryer, a contact dryer, a spray dryer, a mixer dryer, a paddle dryer, a conical screw dryer, a tumble dryer, a drying oven, a rotary kiln, an oven, or a tumble dryer are performed. Also, for drying, combinations of the above-mentioned apparatuses can be used. Drying in process step (h) may, according to one embodiment, be carried out continuously, for example as fluidized bed drying, spray drying, paste flash drying, thin film drying (solidizer), current drying or belt drying. According to a further embodiment of the invention, the drying is carried out discontinuously, for example in a contact dryer, a mixer dryer, a paddle dryer, a conical screw dryer, a tumble dryer, a DTB, a drying oven (circulating air or vacuum).

The drying in process step (h) is generally carried out at a temperature in the range of 150 to 350 ° C, preferably in the range of 250 to 300 ° C, more preferably in the range of 250 to 290 ° C over a period of 1 to 300 minutes, preferably over a period of 60 minutes to 180 minutes, more preferably carried out over a period of 45 to 120 minutes. The atmosphere under which process (h) is carried out is generally an air or inert gas atmosphere such as an argon or nitrogen atmosphere. Preferably, process step (f) is carried out under a nitrogen atmosphere.

In order to improve the polymer compatibility of the functionalized expandable graphite intercalation compounds according to the invention, one or more additives selected from the group consisting of ammonia, boric acid, boric acid derivatives, boric acid mono-, di- and trialkyl esters before or during the drying, according to a preferred embodiment of the invention of the functionalized graphite intercalation compound, Siloxanes, mono-, di-, tri- and tetraalkoxysilanes, linear and cyclic amines, diamines, polyamines, triethylamine, melamine, metal oxides such as zinc, titanium and magnesium oxide, alkali metal, magnesium and aluminum hydroxide added. The additives are, in particular, primary or secondary or tertiary amines according to the general formula NR ₃ , where R independently of one another is H, a substituted or unsubstituted straight-chain or branched alkyl group having 1 to 20, preferably 1 to 10, particularly preferably 1 to 7, most preferably 1 to 3 carbon atoms. Also particularly suitable are piperazine, melamine, alkylbo- and / or zinc oxide. The amount of this additive or these additives can vary over wide ranges and is generally from 0.1 to 99.9 wt .-%, preferably 1 to 75 wt .-%, more preferably 2 to 50 wt .-%, particularly preferably 5 to 30 wt .-%, based on 100 parts by weight of graphite. The addition of the additives can take place, for example, by stirring, spraying, slurrying, generally by mixing, blending or kneading.

The invention further relates to functionalized expandable graphite intercalation compounds obtainable by the methods described above. These expandable graphite intercalation compounds contain A) expandable graphite and

B) at least one phosphorus-containing flame retardant compound, wherein the at least one phosphorus-containing flame retardant compound is at least partially incorporated in the expandable graphite or intercalated or attached. In the context of the invention, it turned out that by the arrival or incorporation of the phosphorus-containing flame retardant compound (s) in or on the structure of the expandable graphite not only increase the expansion temperature of the expandable graphite, but also a very rapid release of flame retardants can be observed. In addition, the graphite intercalation compounds according to the invention have the advantage that they have improved stability at elevated temperatures compared with conventional expandable graphite and also show, due to the immobilization of at least one phosphorus-containing flame retardant compound, lower interactions between flame retardant and polymer. Due to the higher temperature stability, the functionalized, expandable graphite intercalation compounds according to the invention are also suitable for plastics such as PA or PBT, which are processed at high temperatures. In addition, forms a more stable protective layer in case of fire. By the attachment or storage of the at least one phosphorus-containing flame retardant compounds in or on the structure of the expandable graphite on the one hand, the migration of at least one phosphorus-containing flame retardant compound is reduced, whereby a possible softening effect of phosphorus-containing flame retardants is reduced. As a result, the polymer matrix is less damaged, in particular degraded to a lesser extent, so that less damage to the matrix can be observed. In addition, the very rapid release of the flame retardant during the expansion of the expandable graphite causes a phosphate crust to form on the surface of the graphite after swelling, which considerably improves the thermal stability of the graphite crust which forms in the event of fire.

Due to its layered structure, the graphite is able to form special forms of intercalation compounds. In the functionalized expandable Graphitanlagerungsverbindung according to the present invention, while a significant proportion of a phosphorus-containing flame retardant compound is embedded in the interstices of the carbon layers. Another portion of the phosphorus-containing flame retardant compound is located, for example, on the surface of expandable graphite.

In the context of the present invention, the phosphorus-containing flame retardant compounds are organic and inorganic phosphorus-containing compounds in which the phosphorus has the valence state -3 to +5. Under the advertising The term "oxidation state" should be understood as it is reproduced in the textbook on inorganic chemistry by AF Hollemann and E. Wiberg, Walter de Gruyter & Co. (1964, 57th to 70th edition), pages 166 to 177. Phosphorus compounds of valence state -3 to +5 are derived from phosphites (-3), diphosphites (- 2), phosphine oxide (-1), elemental phosphorus (+0) and hypophosphorous acid (+1), phosphorous acid (+3), Hypodiphosphoric acid (+4) and phosphoric acid (+5).

From the large number of phosphorus-containing flame retardant compounds, in particular the inorganic or organic phosphates, phosphites, phosphonates, phosphate esters, red phosphorus and triphenylphosphine oxide, only a few are mentioned by way of example.

Examples of phosphine-containing phosphorus-containing flame retardant compounds having the valence state -3 are aromatic phosphines such as triphenylphosphine, tritolylphosphine, trinonylphosphine, trinaphthylphosphine and tnsnonylphenylphosphine and others. Particularly suitable is triphenylphosphine.

Examples of phosphorus-containing flame retardant compounds of the diphosphine class which have the valence state -2 are tetraphenyldiphosphine, tetranaphthyldiphosphine and others. Particularly suitable is tetranaphthyldiphosphine.

Phosphorus compounds of valence state -1 are derived from the phosphine oxide.

Suitable phosphine oxides of the general formula I.

wherein R ¹ , R ² and R ³ in formula I mean the same or different alkyl, aryl, alkylaryl or cycloalkyl groups having 8 to 40 carbon atoms.

Examples of phosphine oxides are triphenylphosphine oxide, tritolylphosphine oxide, trisynylphenylphosphine oxide, tricyclohexylphosphine oxide, tris (n-butyl) phosphine oxide, tris (n-hexyl) phosphine oxide, tris (n-octyl) phosphine oxide, tris (cyanoethyl) phosphine oxide , Benzylbis (cyclohexyl) phosphine oxide, benzylbisphenylphosphine oxide, phenylbis (n-hexyl) phosphine oxide. Also preferred are oxidized reaction products of phosphine with aldehydes, especially from t-butylphosphine with glyoxal. Particular preference is given to using triphenylphosphine oxide, tricyclohexlyphosphine oxide, tris (n-octyl) - phosphine oxide and tris (cyanoethyl) phosphine oxide, in particular triphenylphosphine oxide.

Also suitable is triphenylphosphine sulfide and its derivates of the phosphine oxides as described above.

Phosphorus of valence state 0 is the elemental phosphorus. Eligible are red and black phosphorus. Preference is given to red phosphorus. Phosphorus compounds of the "oxidation state" +1 are e.g. Hypophosphites of purely organic nature, e.g. organic hypophosphites, such as cellulose hypophosphite esters, esters of hypophosphorous acids with diols, e.g. of 1, 10-dodecyldiol. Also substituted phosphinic acids and their anhydrides, e.g. Diphenylphosphinic can be used. Also suitable are diphenylphosphinic acid, di-p-tolylphosphinic acid, di-cresylphosphinic anhydride. But there are also compounds such as hydroquinone, ethylene glycol, propylene glycol bis (diphenylphosphinic) - u.a. in question. Further suitable are aryl (alkyl) phosphinic acid amides, e.g. Diphenylphosphinic acid dimethylamide and sulfonamidoaryl (alkyl) phosphinic acid derivatives, e.g. p-Tolylsulfonamidodiphenylphosphinsäure. Phosphinic acid esters, hydroquinone and ethylene glycol bis (diphenylphosphinic acid) esters and the bis-diphenylphosphinate of hydroquinone are preferably used.

Phosphorus compounds of the oxidation state +3 are derived from the phosphorous acid. Suitable are cyclic phosphonates derived from pentaerythritol, neopentyl glycol or catechol, e.g. Compounds according to formula II

where R is a C1 to _C4 alkyl radical, preferably a methyl radical, x = 0 or 1 (Amgard P45 from Albright & Wilson).

Furthermore, phosphorus of the valence state +3 in triaryl (alkyl) phosphites, such as triphenylphosphite, tris (4-decylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite or Phenyldidecylphosphit included. But there are also diphosphites, such as Propylene glycol-1, 2-bis (diphosphite) or cyclic phosphites derived from pentaerythritol, neopentyl glycol or catechol, in question.

Particularly preferred are methyl neopentyl glycol phosphonate and phosphite and dimethyl pentaerythritol diphosphonate and phosphite.

As phosphorus compounds of oxidation state +4 are mainly hypodiphosphates, such. Tetraphenyl hypodiphosphate or Bisneopentylhypodiphosphat into consideration. Suitable phosphorus compounds of the oxidation state +5 are, in particular, alkyl- and aryl-substituted phosphates as well as phosphoric and polyphosphoric acids. Examples are phenylbisdodecylphosphate, phenylethylhydrogenphosphate, phenylbis (3,5,5-trimethylhexyl) phosphate, ethyldiphenylphosphate, 2-ethylhexyldi (tolyl) phosphate, diphenylhydrogenphosphate, bis (2-ethylhexyl) -p-tolylphosphate, tritolylphosphate , Bis (2-ethylhexyl) phenyl phosphate, bis (2-ethylhexyl) phosphate, di (nonyl) phenyl phosphate, phenylmethyl hydrogen phosphate, di (dodecyl) p-tolyl phosphate, p-tolyl bis (2,5,5-trimethylhexyl) phosphate or 2-ethylhexyldiphenyl phosphate. Particularly suitable are phosphorus compounds in which each radical is an aryloxy radical. Especially suitable is triphenyl phosphate and resorcinol bis (diphenyl phosphate) and its nucleus-substituted derivatives of general formula III (RDP):

in which the substituents in formula (III) have the following meanings:

R ⁴ - R ^{7 is} an aromatic radical having 6 to 20 C atoms, preferably a phenyl radical which may be substituted by alkyl groups having 1 to 4 C atoms, preferably methyl, R is a xylene radical or dihydric phenol radical, preferably

and n an average value between 0.1 to 100, preferably 0.5 to 50, in particular 0.8 to 10 and very particularly 1 to 5.

The commercially available products under the trademark RDP Fyroflex ^® or Fy- rol ^® -RDP (Akzo) and CR-S 733 (Daihachi) are due to the manufacturing process, mixtures of about 85% RDP (n = 1) with ca. 2.5% of triphenyl phosphate and about 12.5% oligomeric portions in which the degree of oligomerization is usually less than 10.

Furthermore, cyclic phosphates can also be used. Particularly suitable here is diphenylpentaerythritol diphosphate and phenylneopentyl phosphate.

In addition to the above-mentioned low molecular weight phosphorus compounds are still oligomeric and polymeric phosphorus compounds in question. Such polymeric, halogen-free organic phosphorus compounds containing phosphorus in the polymer chain are formed, for example, in the preparation of pentacyclic, unsaturated phosphine dihalides, as described, for example, in DE-A 20 36 173. The molecular weight measured by vapor pressure osmometry in dimethylformamide, the Polyphospholinoxide should be in the range of 500 to 7000, preferably in the range of 700 to 2000.

Further, inorganic coordination polymers of aryl (alkyl) phosphinic acids such as e.g. Poly-ß-sodium (l) -methylphenylphosphinat be used. Their preparation is given in DE-A 31 40 520. The phosphorus has the oxidation number +1.

Furthermore, such halogen-free polymeric phosphorus compounds may be prepared by the reaction of a phosphonic acid chloride, such as a phosphonic acid chloride. Phenyl, methyl, propyl, styryl and vinylphosphonic dichloride with bifunctional phenols, e.g. Hydroquinone, resorcinol, 2,3,5-trimethylhydroquinone, bisphenol-A, tetramethylbiphenol-A arise.

Further halogen-free polymeric phosphorus compounds which may be present in the graphite intercalation compounds according to the invention are prepared by reaction of phosphorus oxychloride or phosphoric ester dichlorides with a mixture of mono-, bi- and trifunctional phenols and other compounds carrying hydroxyl groups (see Houben-Weyl-Müller, US Pat. Thieme-Verlag Stuttgart, organic phosphorus compounds Part II (1963)). Furthermore, polymeric phosphonates can be prepared by transesterification reactions of phosphonic acid esters with bifunctional phenols (cf DE-A 29 25 208) or by reactions of phosphonic acid esters with diamines or diamides or hydrazides (compare US Patent 4,403,075). In question, however, also the inorganic ammonium polyphosphate, melamine phosphate and melamine polyphosphate. It is also possible to use oligomeric pentaerythritol phosphites, phosphates and phosphonates according to EP-B 8 486, for example Antiblaze® 19 (registered trademark of Mobil Oil) (see formulas (IV) and (V)):

where the substituents in the formulas (IV) and (V) have the following meanings:

R ¹ , R ^{2 is} hydrogen, C to C ₆ alkyl, which optionally contains one hydroxyl group, preferably C to C ₄ alkyl, linear or branched, for example methyl, ethyl, n-propyl, iso-propyl, n-butyl, tert Butyl, n-pentyl; phenyl; wherein preferably at least one radical R ¹ or R ² , in particular R ¹ and R ² , is hydrogen;

R ^{3 is} C 1 -C 10 -alkylene, linear or branched, for example methylene, ethylene, n-propylene, iso-propylene, n-butylene, tert-butylene, n-pentylene, n-octylene, n-dodecylene;

Arylene, e.g. Phenylene, naphthylene;

Alkylarylene, e.g. Methyl-phenylene, ethyl-phenylene, tert-butyl-phenylene, methyl-naphthylene, ethyl-naphthylene, tert-butyl-naphthylene;

Arylalkylene, for example phenylmethylene, phenylethylene, phenylpropylene, phenylbutylene; M is an alkaline earth, alkali metal, Al, Zn, Fe, boron; m is an integer of 1 to 3; n is an integer of 1 and 3 and x 1 or 2.

Particular preference is given to compounds of the formula (IV) in which R ¹ and R ^{2 are} hydrogen, where M is preferably Ca, Zn or Al and calcium phosphinate is very particularly preferred as the compound.

Such products are commercially available, for example, as calcium phosphinate.

Suitable salts of the formula (IV) or (V) in which only one radical R ¹ or R ^{2 is} hydrogen are, for example, salts of phenylphosphinic acid, their Na and / or Ca salts being preferred.

Further preferred salts have a hydroxyl-containing alkyl radical R ¹ and / or R ² . These are obtainable, for example, by hydroxymethylation. Preferred compounds are Ca, Zn and Al salts.

Preference is furthermore given to phosphorus compounds of the general formula (VI):

where the substituents in formula (VI) have the following meanings:

R ¹ to R ²⁰ independently of one another are hydrogen, a linear or branched alkyl group having up to 6 C atoms, n an average value of 0.5 to 50 and

X is a single bond, C = O, S, S0 ₂ , C (CH ₃ ) ₂ . Preferred phosphorus-containing flame retardant compounds are those of the formula (VI) in which R ¹ to R ²⁰ independently of one another denote hydrogen and / or a methyl radical. In the event that R ¹ to R ²⁰ independently of one another denote a methyl radical, preference is given to those compounds in which the radicals R ¹ , R ⁵ , R ⁶ , R ¹⁰ , R ¹¹ , R ¹⁵ , R ¹⁶ , R ²⁰ in the ortho position to the oxygen of the phosphate group represent at least one methyl radical. Preference is furthermore given to compounds in which one methyl group is present per aromatic ring, preferably in the ortho position, and the other radicals are hydrogen.

Particularly preferred substituents S0 ₂ and S, and most preferably C (CH ₃ ) ₂ for X in the above formula (VI). n in the above formula (VI) is preferably 0.5 to 5, in particular 0.7 to 2, and especially about 1, as the average value.

The indication of n as an average value results from the preparation of the compounds listed above, so that the degree of oligomerization is usually less than 10 and small amounts (usually <5 wt .-%) are included in triphenyl phosphate, this being different from batch to batch. Such compounds are commercially available as CR-741 from Daihachi.

According to a further preferred embodiment of the invention, the at least one phosphorus-containing flameproofing compound is a compound of the general formula PO (OR) ₃ , where R is independently H, a substituted or unsubstituted straight-chain or branched alkyl group having 1 to 20, preferably with 1 to 10, more preferably 1 to 7, most preferably 1 to 3 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted naphthyl.

According to a further preferred embodiment of the invention, the at least one phosphorus-containing flame retardant compound is a compound of the general formula PO (R) ₃ , where R is, independently of one another, H, OH, a substituted or unsubstituted straight-chain or branched alkyl group having 1 to 20, preferably 1 to 10, more preferably 1 to 7, most preferably 1 to 3 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted alkoxy. "Alkyl" or "alkyl group" means a saturated aliphatic hydrocarbon group which may be straight chain or branched and may have from 1 to 20 carbon atoms in the chain. Preferred alkyl groups may be straight-chain or branched and have from 1 to 10 carbon atoms in the chain. Branched means that a lower alkyl group, such as methyl, ethyl or propyl, is attached to a linear alkyl chain. Alkyl is, for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl ) 2-ethylhexyl, 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2, 2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2- pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl 1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, 1-heptyl, 1-octyl, 1 -nonyl, 1-decyl, 1-undecyl, 1 -dodecyl, 1-tetradecyl, 1-hexadecyl and 1-octadecyl. Preference is given, for example, to methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl , 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl and 2,2-dimethyl-1-propyl , Particularly preferred are methyl, ethyl and propyl.

"Lower alkyl" means an alkyl group having from 1 to about 7 carbon atoms.

"Alkoxy" means an alkyl-O-group in which "alkyl" has the meaning described above. Lower alkoxy groups are preferred. Exemplary groups include methoxy, ethoxy, n-propoxy, i -propoxy and n-butoxy. "Substituted alkyl" means that the alkyl group is substituted with one or more substituents selected from alkyl, optionally substituted aryl, optionally substituted aralkyl, alkoxy, nitro, carboalkoxy, cyano, halo, alkylmercaptyl, trihaloalkyl or carboxyalkyl. "Substituted "generally means that the alkyl group or the benzyl group or the phenyl group or the naphthyl group having one or more substituents selected from alkyl, optionally substituted aryl, optionally substituted aralkyl, alkoxy, nitro, carboalkoxy, cyano, halo, alkylmercaptyl, trihaloalkyl or Carboxyalkyl is substituted.

"Aryl" means phenyl or naphthyl. "Aralkyl" means an alkyl group substituted with an aryl group "Substituted aralkyl" and "substituted aryl" mean that the aryl group or aryl group of the aralkyl group has one or more substituents selected from alkyl, Alkoxy, nitro, carboalkoxy, cyano, halo, alkyl mercaptyl, trihaloalkyl or carboxyalkyl substituted.

"Halogen" (or "halo") means chloro, fluoro, bromo or iodo. According to a further preferred embodiment, it is a salt of the above-defined compound PO (OR) ₃ or PO (OR) ₂ R or PO (R) ₃ , in particular an alkali or alkaline earth metal salt or an AI, Zn, Fe - boron salt. According to a particularly preferred embodiment of the invention, the phosphorus-containing flame retardant compound is at least one compound selected from dimethylmethylphosphonate, diethylethylphosphonate, bis (2-ethylhexyl) phosphate, triphenylphosphate (TPP), resorcinol bis (diphenylphosphate) (RDP) and diethylbenzylphosphonate.

The proportion of the phosphorus-containing flame retardant compound incorporated in the functionalized expandable graphite can vary over a wide range and, based on the phosphorus, is generally in the range from 0.1 to 20% by weight, preferably in the range from 0.5 to 15 wt .-%, particularly preferably in the range of 1 to 10 wt .-% with respect to the total weight of the expandable graphite.

Expandable graphite is known to those skilled in the art and described in the literature, it is so-called expandable graphite (heat or heat expandable graphite). This is usually derived from natural or artificial graphite.

In general, expandable graphite can be prepared, for example, by oxidation and intercalation of natural and / or artificial graphite. The preparation is known to the person skilled in the art and will not be explained in detail at this point.

According to a preferred embodiment, the surface of the functionalized expandable graphite intercalation compound may be coated with a coating agent for better compatibility with the polymer matrices in which the flame retardant compound is incorporated, for example with the silane layers known to those skilled in the art.

In the event that the functionalized expandable graphite intercalation compound has been obtained by the above-mentioned oxidation, it may be necessary to add one or more alkaline compound (s), because the expandable graphite (by the acid contained) would otherwise cause corrosion of the molding compounds and / or bearing compounds May cause manufacturing equipment of such molding compounds. In particular, alkali metal compounds such as hydroxides of the alkali metals z. As NaOH, KOH or LiOH, and Mg (OH) ₂ or aluminum hydroxides can in amounts of 1 wt .-% to 50 wt .-%, preferably from 5 wt .-% to 10 wt .-%, particularly preferably from 8 Wt .-% to 12 wt .-%, based on 100 wt .-% of the expandable graphite intercalation compound are added. The mixture is advantageously carried out before the components are compounded. Due to the presence or incorporation of the at least one phosphorus-containing flame retardant compound into the layer structure of the expandable graphite, the functionalized expandable graphite intercalation compounds according to the invention expand at higher temperatures than expandable graphite in which no phosphorus-containing flame retardant compounds are incorporated. The expansion temperature, that is the temperature at which the functionalized expandable graphite intercalation compounds expand to up to 300 times their original volume, is in the range of 100 to 600 ° C, preferably in the range of 150 to 400 ° C, more preferably in the range of 270 ° C to 370 ° C, which makes it possible to incorporate the expandable Graphiteinlagerungsverbindungen invention also using higher temperatures in the range of> 290 ° C in the corresponding flame-retardant polymers. The invention further relates to thermoplastic molding compositions which contain the expandable graphite intercalation compounds according to the invention.

Contain the expandable graphite intercalation compounds containing thermoplastic molding compositions

C) 50 to 99% by weight, preferably 60 to 97% by weight, particularly preferably 70 to 95% by weight of at least one thermoplastic polymer,

D) 1 to 50 wt .-%, preferably 3 to 40 wt .-%, particularly preferably 5 to 30 wt .-% of one or more expandable graphite intercalation compounds as defined above,

E) 0 to 49 wt .-%, preferably 0 to 45 wt .-%, particularly preferably 0 to 25 wt .-% of further additives, wherein the weight percent in each case based on the total weight of components C), D) and E) and together give 100% by weight.

In principle, all thermoplastic polymers known to the person skilled in the art and described in the literature are suitable as thermoplastic polymers or thermoplastic molding compositions.

Suitable for example

Polyolefins such as polyethylene and polypropylene,

polyvinyl chloride,

Styrene polymers such as polystyrene (impact or non-impact modified), impact-modified vinyl aromatic copolymers such as ABS (acrylonitrile-butadiene-styrene), ASA (acrylonitrile-styrene-acrylate) and MABS (transparent ABS containing methacrylate units),

Styrene-butadiene block copolymers ("SBC"), in particular styrene-based thermoplastic elastomers ("S-TBE"),

polyamides,

Polyesters such as polyethylene terephthalate (PET), polyethylene terephthalate glycol (PETG) and polybutylene terephthalate (PBT),

Polycarbonate (for example, Makroion from Bayer AG), polymethyl methacrylate (MMA),

Polyoxymethylene (POM),

polyurethanes,

Poly (ether) sulfones and

Polyphenylene oxide (PPO).

Preferably, the thermoplastic polymer is one or more polymers selected from the group ASA, ABS, polyamides and polyesters.

Preferred impact-modified vinylaromatic copolymers are impact-modified copolymers of vinylaromatic monomers and vinyl cyanides (SAN). ASA polymers and / or ABS polymers are preferably used as impact-modified SAN, as well as (meth) acrylate-acrylonitrile-butadiene-styrene polymers ("MABS", transparent ABS), but also blends of SAN, ABS, ASA and MABS other thermoplastics such as polycarbonate, polyamide, polyethylene terephthalate, polybutylene terephthalate, PVC, polyolefins.

ASA polymers are generally understood to be impact-modified SAN polymers in which rubber-elastic graft copolymers of vinylaromatic compounds, in particular styrene, and vinyl cyanides, in particular acrylonitrile, are present on polyalkylacrylate rubbers in a copolymer matrix of, in particular, styrene and / or .alpha.-methylstyrene and acrylonitrile.

ABS polymers are generally understood to be impact-modified SAN polymers in which diene polymers, in particular 1,3-polybutadiene, are present in a copolymer matrix of, in particular, styrene and / or α-methylstyrene and acrylonitrile.

Suitable thermoplastic polymers are, in principle, all SBCs known to the person skilled in the art and described in the literature. Preference is given to using S-TPE, in particular those having an elongation at break of more than 300%, particularly preferably more than 500%, in particular more than 500% to 600% (these and all others Yields and tensile strengths given in this application are determined in the tensile test according to ISO 527-2: 1996 on test specimens of type 1 BA (Appendix A of the cited standard: "small specimens").) A SBC or S-TPE is particularly preferably mixed in a linear one or star-shaped styrene-butadiene block copolymer with external polystyrene blocks S and, between these, styrene-butadiene copolymer blocks with a random styrene / butadiene distribution (S / B) _random, or with a styrene gradient (S / B) _ta by about (eg Styrolux ^® or particular styrene Flex ^® BASF SE, K-Resin ^® CPC; other components C) advertising the marketed under the brands Cariflex ^®, Kraton ^®, Tufprene ^®, Asaflex ^®).

The total butadiene content of the SBC is preferably in the range of 15 to 50 wt .-%, particularly preferably in the range of 25 to 40 wt .-%; Accordingly, the total styrene content is preferably in the range from 50 to 85% by weight, particularly preferably in the range from 60 to 75% by weight.

Preferably, the styrene-butadiene block (S / B) consists of 30 to 75% by weight of styrene and 25 to 70% by weight of butadiene. The proportion of polystyrene block S is preferably in the range from 5 to 40% by weight, in particular in the range from 25 to 35% by weight, based on the total block copolymer. The proportion of the copolymer blocks S / B is preferably in the range of 60 to 95 wt .-%, in particular in the range of 65 to 75 wt .-%. Particularly preferred are linear styrene-butadiene block copolymers of the general structure S- (S / B) -S with one or more, lying between the two S blocks, a static styrene / butadiene distribution blocks having (S / B) _rand om Such block copolymers are obtainable by anionic polymerization in a nonpolar solvent with the addition of a polar cosolvent or a potassium salt, as described, for example, in WO 95/35335 A2 and WO 97/40079 A2, respectively.

The vinyl content is understood to mean the relative proportion of 1,2-linkages of the diene units, based on the sum of the 1,2-, 1,4-cis and 1,4-trans linkages. The 1,2-vinyl content in the styrene-butadiene copolymer block (S / B) is preferably below 20%, in particular in the range from 10 to 18%, particularly preferably in the range from 12 to 16%. The unsaturated moieties, especially those derived from butadiene, the thermoplastic TPE and SBC can also be fully or partially hydrogenated. In the case of (partially) hydrogenated SBC, the proportion of 1,2-linkages of the diene unit before the hydrogenation step can also be up to 60%. Also suitable as a thermoplastic are partially crystalline polyolefins, such as homopolymers or copolymers of ethylene, propylene, butene-1, pentene-1, hexene-1, 4-methylpentene-1 and ethylene copolymers with vinyl acetate, vinyl alcohol, ethyl acrylate, butyl acrylate or methacrylate. The thermoplastic used is preferably a high-density polyethylene (HDPE), polypropylene (PP), ethylene-vinyl acetate copolymer (EVA) or ethylene-acrylic copolymer. Particularly preferred is polypropylene.

The polycarbonates suitable as thermoplastic preferably have a molecular weight (weight average M _w , determined by gel permeation chromatography in tetrahydrofuran against polystyrene standards) in the range of 10,000 to 60,000 g / mol. They are obtainable, for example, in accordance with the processes of DE-B 1 300 266 by interfacial polycondensation or in accordance with the process of DE-A 1 495 730 by reacting diphenyl carbonate with bisphenols. Preferred bisphenol is 2,2-di (4-hydroxyphenyl) propane, generally - as also mentioned below - called bisphenol A.

Instead of bisphenol A, it is also possible to use other aromatic dihydroxy compounds, in particular 2,2-di (4-hydroxyphenyl) pentane, 2,6-dihydroxynaphthalene, 4,4'-dihydroxydiphenylsulfane, 4,4'-dihydroxydiphenyl ether, 4,4 '-Dihydroxy-diphenylsulfite, 4,4'-dihydroxydiphenylmethane, 1,1-di- (4-hydroxyphenyl) ethane, 4,4-dihydroxydiphenyl or dihydroxydiphenylcycloalkanes, preferably dihydroxydiphenylcyclohexanes or dihydroxycyclopentanes, in particular 1,1-bis ( 4-hydroxyphenyl) - 3,3,5-trimethylcyclohexane and mixtures of the aforementioned dihydroxy compounds.

Particularly preferred polycarbonates are those based on bisphenol A or bisphenol A together with up to 80 mol% of the abovementioned aromatic dihydroxy compounds. Polycarbonates which are particularly suitable as thermoplastics are those which contain units which are derived from resorcinol or alkyl resorcinol esters, as described, for example, in WO 00/61664, WO 00/15718 or WO 00/26274; These polycarbonates are selling, for example, General Electric Company under the trademark SollX ^®.

It is also possible to use copolycarbonates according to US Pat. No. 3,737,409; Of particular interest are copolycarbonates based on bisphenol A and di- (3,5-dimethyl-dihydroxyphenyl) sulfone, which are characterized by a high heat resistance. It is also possible to use mixtures of different polycarbonates. The average molecular weights (weight average M _w , determined by gel permeation chromatography in tetrahydrofuran against polystyrene standards) of the polycarbonates are, according to the invention, in the range from 10,000 to 64,000 g / mol. They are preferably in the range from 15,000 to 63,000, in particular in the range from 15,000 to 60,000 g / mol. This means that the polycarbonates relative solution viscosities in the range of 1, 1 to 1, 3, measured in 0.5 wt .-% solution in dichloromethane at 25 ° C, preferably from 1, 15 to 1, 33, have. The relative solution viscosities of the polycarbonates used preferably do not differ by more than 0.05, in particular not more than 0.04.

The polycarbonates can be used both as regrind and in granulated form.

In general, any aromatic or aliphatic thermoplastic polyurethane is suitable as the thermoplastic, preferably amorphous aliphatic thermoplastic polyurethanes which are transparent are suitable. Aliphatic thermoplastic polyurethanes and their preparation are known in the art, for example from EP-B1 567 883 or DE-A 10321081, and are commercially available, for example under the trade marks Texin ^® and Desmopan ^® Bayer Aktiengesellschaft.

The thermoplastic molding compositions according to the invention may contain one or more additives other than components C) and B) as component E). In principle, all plastic additives known to the person skilled in the art and described in the literature are suitable. Plastic additives for the purposes of the present invention are, for example, stabilizers and antioxidants, agents against heat decomposition and decomposition by ultraviolet light, lubricants and mold release agents, dyes and pigments and plasticizers and fibers, for example glass fibers or carbon fibers. Oxidation retarders and heat stabilizers which can be added to the thermoplastic molding composition according to the invention are, for example, halides of Group I metals of the periodic table, for example sodium, potassium, lithium halides. Furthermore, zinc fluoride and zinc chloride can be used. Further, sterically hindered phenols, hydroquinones, substituted members of this group, secondary aromatic amines, optionally in conjunction with phosphorus-containing acids or their salts, and mixtures of these compounds, preferably in concentrations up to 1 wt .-%, based on the weight of the thermoplastic Molding compounds, usable. Examples of UV stabilizers are various substituted resorcinols, salicylates, benzotriazoles and benzophenones, which are generally used in amounts of up to 2 wt .-%, based on the weight of the thermoplastic molding compositions. Lubricants and mold release agents, which can generally be added in amounts of up to 1% by weight, based on the weight of the thermoplastic molding compositions, are stearic acid, stearyl alcohol, stearic acid alkyl esters and amides and esters of pentaerythritol with long-chain fatty acids. It is also possible to use salts of calcium, zinc or aluminum of stearic acid and dialkyl ketones, for example distearyl ketone. Zinc, magnesium and calcium stearates and N, N'-ethylene-bis-stearamide are particularly suitable according to the invention.

As glass fibers, it is possible to use in the novel molding materials all glass fibers known to the person skilled in the art and described in the literature (see, for example, Milewski, JV, Katz, HS "Handbook of Reinforcements for Plastics", p. 233 et seq., Van Nostrand Reinholt Company Inc., 1987).

According to a preferred embodiment, the thermoplastic molding compositions contain one or more alkaline compounds which neutralize the acid usually contained in the expandable graphite. These compounds are in particular alkali metal compounds such as hydroxides of alkali metals z. B. NaOH, KOH or LiOH, and Mg (OH) ₂ or aluminum hydroxides, and compounds selected from Borsäuremono-, di- and trialkyl, siloxanes, mono-, di-, tri- and Tetraalkoxysi- lane, linear and cyclic amines, Diamines, polyamines, triethylamine and melamine.

Furthermore, the invention relates to processes for the preparation of the thermoplastic molding compositions, by means of which flame-retardant thermoplastic molding compositions can be obtained. The thermoplastic molding compositions are usually mixed by melt mixing of components C), D) and, if present, E) in conventional mixing devices such as single- or twin-screw extruders, Brabender mills, Banbury mills, Buss kneaders or Farrel mixers and then extruded. After extrusion, the extrudate can be cooled and comminuted. It is also possible to premix individual components and then to add the remaining starting materials individually and / or likewise mixed. The mixing temperatures are usually 200 to 280 ° C.

The flame-retardant thermoplastic molding compositions according to the invention have, compared with known flame-retardant molding compositions, an improved flameproofing effect as already described above. The invention will be explained in more detail by means of examples.

example 1

Preparation: 130 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

750 ml of bis (2-ethylhexyl) phosphate [Merck]

Procedure: First, the expanded graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and rinsed well (at least 30 min) with nitrogen. Subsequently, the organic P-component was added and heated to T _inne n = 80 ° C with stirring (160 U / min and nitrogen purge). After a test run time of 5 hours at 80 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

Post-treatment: The residual moisture modified expandable graphite was introduced into a rotary ball flask made of Duranglas (mass 150-200g) and then heated under air.

Heating program: The mixture was heated from room temperature to 280 ° C. in the course of 60 minutes, kept at 280 ° C. for 120 minutes and then cooled again to room temperature.

Example 2

Preparation: 550 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1850 ml bis (2-ethylhexyl) phosphate [Merck]

Procedure: The expandable graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and the reaction vessel was purged well (at least 30 min) with nitrogen. Subsequently, the organic P-component was added, with stirring (160 rev / min and nitrogen purging) to T _inne n = 80 ° C heated and maintained at 80 ° C for 5 hours. At the end of the reaction time, the mixture was cooled to room temperature and the modified expandable graphite was filtered off with suction through a glass suction funnel (POR 4).

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150 - 200g) filled and then heated under air.

Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 250 ° C. for 120 minutes and then cooled.

Example 3

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1950 ml bis (2-ethylhexyl) phosphate [Merck]

Procedure: The expandable graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and the reaction vessel was well (at least 30 min) with Flushed with nitrogen. Subsequently, the organic P-component was added, with stirring (160 rev / min and nitrogen purging) to T _inne n = 80 ° C heated and maintained at 80 ° C for 5 hours. After the reaction time had elapsed, it was cooled to room temperature and the modified expandable graphite was sucked off through a glass filter basket (POR 4).

After treatment: The still residual modified expanded graphite was in a

Example 4 (with chemical aftertreatment)

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1950 ml bis (2-ethylhexyl) phosphate [Merck]

Triethylborate [Merck]

Procedure: The expanded graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and the reaction vessel was purged well (at least 30 min) with nitrogen. Subsequently, the organic P-component was added, with stirring (160 rev / min and nitrogen purging) to T _inne n = 80 ° C heated and maintained at 80 ° C for 5 hours. After the reaction time had elapsed, it was cooled to room temperature and the modified expandable graphite was sucked off through a glass filter basket (POR 4).

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150-200g) filled with Triethylborat added (for example, 140g graphite with 40g triethyl borate) and then baked.

Example 5

Preparation: 150 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

750 ml of dimethyl methylphosphonate [ABCR]

Procedure: The expanded graphite was placed in a 3000 ml jacketed vessel with anchor stirrer, which was then thoroughly purged with nitrogen (at least 30 min). After addition of the organic P component (nitrogen atmosphere), the resulting suspension was heated with stirring (160 U / min and nitrogen purge) to T _inne n = 80 ° C and stirred for 5 hours at 80 ° C. The reaction mixture was then cooled again to room temperature and the modified expandable graphite separated via a glass suction filter (POR 4).

After treatment: The still residual modified expanded graphite was in a

Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 250 ° C. for 120 minutes and then cooled again to room temperature.

Example 6

Preparation: 550 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1750 ml of dimethyl methylphosphonate [ABCR]

Procedure: The expanded graphite was placed in a 3000 ml jacketed vessel with anchor stirrer, which was then thoroughly purged with nitrogen (at least 30 min). After addition of the organic P component (nitrogen atmosphere), the resulting suspension was heated with stirring (160 U / min and nitrogen purge) to T _inne n = 80 ° C and stirred for 5 hours at 80 ° C. The reaction mixture was then cooled again to room temperature and the modified expandable graphite was separated off via a glass suction funnel (POR 4).

After treatment: The still residual modified expanded graphite was in a

Example 7

Preparation: 200 g expandable graphite (Nord-Min 503)

750ml dimethylmetyl phosphonate [ABCR]

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150 - 200g) filled and then heated under air. Heating program: The mixture was heated to 290 ° C. in the course of 60 minutes, kept at 250 ° C. for 120 minutes and then cooled again to room temperature.

Example 8 (with chemical aftertreatment)

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

2000 ml of dimethyl methylphosphonate [ABCR]

Ammonia, gaseous

Procedure: The expanded graphite was placed in a 3000 ml jacketed vessel with an anchor stirrer, which was then thoroughly rinsed with nitrogen (at least 30 min). After addition of the organic P component

(Nitrogen atmosphere), the suspension obtained was heated with stirring (160 U / min and nitrogen purge) to T _inne n = 80 ° C and stirred for 5 hours at 80 ° C. The reaction mixture was then cooled again to room temperature and the modified expandable graphite was separated off via a glass suction funnel (POR 4).

After treatment: The still residual modified expanded graphite was in a

Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 250 ° C. for 120 minutes and then cooled again to room temperature. Further treatment: The heated product was then placed in a with an am

Bottom glass frit provided filled glass tube. Then it flows through from bottom to top with NH ₃ until there is no reaction heat.

Example 9 (with chemical aftertreatment)

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1950 ml of dimethyl methylphosphonate [ABCR] about 80 mg of triethyl borate [Merck]

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150 - 200g) filled, with Triethylborat added (eg 140g graphite with 40g triethyl borate) and then heated under air.

Example 10

Preparation: 500 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1800 ml of dimethyl methylphosphonate [ABCR]

Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 120 ° C. for 250 minutes and then cooled to room temperature.

Example 11 (with chemical aftertreatment)

Preparation: 500 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1800 ml of dimethyl methylphosphonate [ABCR]

Piperazine [Merck]

Post-treatment: The residual moisture modified expandable graphite was placed in a rotary ball flask made of Duranglas (mass 150-200g), treated with piperazine (eg 100g modified expandable graphite with 24g piperazine) and then heated under air. Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 120 ° C. for 250 minutes and then cooled to room temperature.

Example 12 (with chemical aftertreatment)

Preparation: 500 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1800 ml of dimethyl methylphosphonate [ABCR]

Tetraethoxysilane (TEOS) [Alfa Aesar]

Aftertreatment: The residual moisture modified expanded graphite was loaded into a Duranglas rotary ball flask (mass 150-200g), added with TEOS (e.g., 100g modified expanded graphite with 50g TEOS, e.g., 100g modified expanded graphite with 100g TEOS) and then baked in air.

Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 120 ° C. for 250 minutes and then cooled to room temperature. Example 13 (with chemical aftertreatment)

Preparation: 500 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1800 ml of dimethyl methylphosphonate [ABCR]

Triethylamine [Aldrich]

Post-treatment: The residual moisture modified expandable graphite was placed in a rotary ball flask made of Duranglas (mass 150-200g), mixed with triethylamine (eg 100g modified expandable graphite with 50g triethylamine) and then heated under air. Heating program: The mixture was heated to 250 ° C. in the course of 60 minutes, kept at 120 ° C. for 250 minutes and then cooled to room temperature.

Example 14

Preparation: 150 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

750 ml of diethylbenzylphosphonate [ABCR]

Aftertreatment: The remaining wet expanded graphite was poured into a rotary ball flask made of Duranglas (mass 150-200g) and then heated under air.

Heating program: In 60 min was heated to 240 ° C, held for 120min at 240 ° C and then cooled again to room temperature.

Example 15

Preparation: 300 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1000 ml of diethylbenzylphosphonate [ABCR]

After treatment: The still residual modified expanded graphite was in a

Heating program: The mixture was heated to 240 ° C. in the course of 60 minutes, kept at 240 ° C. for 120 minutes and then cooled again to room temperature. Example 16

Preparation: 150 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

750 ml of diethylbenzylphosphonate [ABCR]

Procedure: The expandable graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and thoroughly purged with nitrogen (at least 30 min). This was followed by the addition of the organic P component. Thereafter, the suspension was heated with stirring (160 U / min) in a nitrogen stream flushing) to T _inne n = 80 ° C and held at 80 ° C for 5 hours. The suspension was then cooled to room temperature and then filtered with suction through a glass suction filter (POR 4).

Post-treatment: The resulting, still residual wet modified expandable graphite was introduced into a rotary ball flask made of Duranglas (mass 150-200g) and then heated under air.

Heating program: The mixture was heated to 240 ° C. in the course of 60 minutes, 240 ° C. was held for 120 minutes and then cooled again to room temperature.

Example 17

Preparation: 200 g expandable graphite (Nord-Min 503)

750 ml of diethylbenzylphosphonate [ABCR]

Heating program: was heated to 290 ° C in 60 min, 290 ° C were held for 120 min and then cooled again to room temperature. Example 18

Preparation: 200 g expandable graphite (Nord-Min 503)

750 ml of diethyl ethylphosphonate [ABCR]

Procedure: The expandable graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and thoroughly purged with nitrogen (at least 30 min). This was followed by the addition of the organic P component.

The suspension was then stirred (160 rpm) in a stick stream flushing) heated to T _inne n = 80 ° C and held at 80 ° C for 5 hours. The suspension was then cooled to room temperature and then filtered with suction through a glass suction filter (POR 4).

Heating program: was heated to 290 ° C in 60 min, 290 ° C were held for 120 min and then cooled again to room temperature.

Example 19

Preparation: 300 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1000 ml of diethyl ethylphosphonate (98%) [ABCR]

Heating program: The mixture was heated to 270 ° C. in the course of 60 minutes, 270 ° C. was held for 120 minutes and then cooled again to room temperature.

Example 20 (with chemical aftertreatment)

Preparation: 300 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1000 ml of diethyl ethylphosphonate (98%) [ABCR]

about 80 mg of triethylborate [Merck]

Aftertreatment: The remaining, still moist, modified expandable graphite was placed in a rotary ball flask made of Duranglas (mass 150-200g). filled, mixed with triethyl borate (eg 140 g graphite with 40 g of triethyl borate) and then heated under air.

Example 21

Preparation: 150 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

750 ml of polyphosphoric acid

Procedure: The expanded graphite was placed in a 3000 ml jacketed vessel with anchor stirrer, which was then thoroughly purged with nitrogen (at least 30 min). After addition of the P component (nitrogen atmosphere), the resulting suspension was heated to T _inne n = 80 ° C with stirring (160 U / min and nitrogen purge) and stirred at 80 ° C for 5 hours. The reaction mixture was then cooled again to room temperature and the modified expandable graphite was separated off via a glass suction funnel (POR 4).

Post-treatment The only residual moisture modified expandable graphite was in a

Heating program: In 60 min was heated to 230 ° C, held for 120min at 230 ° C and then cooled again to room temperature.

Example 22

Preparation: 5.40 g of graphite (UF 298) [Kropfmühl AG]

19.9 g of polyphosphoric acid [105%] 40.1 g of HNO ₃ [65%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Magnetic stirrer filled and rinsed well (at least 30 min) with nitrogen. Subsequently, the phosphoric acid and then the nitric acid was added and heated to T _inne n = 30 ° C with stirring (about 200 U / min and nitrogen purge). After a test run time of 5 hours at 30 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

Example 23

Preparation: 4.97 g graphite (UF 298) [Kropfmühl AG]

32.02 g of polyphosphoric acid [105%] 32.31 g of HNO3 [65%] Procedure: First, the graphite was filled into a 100 ml two-necked flask with magnetic stirrer and rinsed well (at least 30 min) with nitrogen. Subsequently, the phosphoric acid and then the nitric acid was added and heated to T _inne n = 30 ° C with stirring (about 200 U / min and nitrogen purge). After a test run time of 5 hours at 30 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4). Example 24

Preparation: 5.40 g of graphite (UF 298) [Kropfmühl AG]

39.88 g of polyphosphoric acid [105%] 20.12 g of HNO ₃ [65%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Example 25

Preparation: 4.89 g of graphite (UF 298) [Kropfmühl AG]

44.90 g of polyphosphoric acid [105%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Example 26

Preparation: 4.89 g of graphite (UF 298) [Kropfmühl AG]

47.91 g of polyphosphoric acid [105%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Filled with magnetic stirrer and stirred well (at least 30 min) with nitrogen. flushes. Subsequently, the phosphoric acid and then the nitric acid was added and heated to T _inne n = 30 ° C with stirring (about 200 U / min and nitrogen purge). After a test run time of 5 hours at 30 ° C., the reaction mixture was cooled and then passed through a glass filter chute

(POR 4) sucked off.

Example 27

Preparation: 5.42 g graphite (UF 298) [Kropfmühl AG]

19.89 g of polyphosphoric acid [105%]

26.01 g HN0 ₃ [100%]

10.00 g of triethyl borate [Merck]

Procedure: First, the graphite was in a 100ml two-necked flask with

Magnetic stirrer filled and rinsed well (at least 30 min) with nitrogen. Subsequently, the phosphoric acid and then the nitric acid was added and heated to T _inne n = 40 ° C with stirring (about 200 U / min and nitrogen purge). After a test run time of 5 hours at 40 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

Post-treatment: The residual moisture modified graphite was introduced into a rotary ball flask made of Duranglas with the triethyl borate (10 g on 5 g graphite) and then heated under N ₂ .

Heating program: The mixture was heated to 200 ° C. in the course of 60 minutes, held at 120 ° C. for 120 minutes and then cooled to room temperature.

Example 28

Preparation: 5.12 g graphite (UF 298) [Kropfmühl AG]

39.92 g of polyphosphoric acid [105%]

10.00 g of triethyl borate [Merck]

Procedure: First, the graphite was in a 100ml two-necked flask with

Magnetic stirrer filled and rinsed well (at least 30 min) with nitrogen. Subsequently, the phosphoric acid and then the nitric acid was added and heated to _ηηβη = 40 ° C with stirring (about 200 U / min and nitrogen _purge ). After a test run time of 5 hours at 40 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4). Post-treatment: The residual moisture modified graphite was introduced into a rotary ball flask made of Duranglas with the triethyl borate (10 g on 5 g graphite) and then heated under N ₂ .

Example 29

Preparation: 5.21 g graphite (UF 298) [Kropfmühl AG]

39.90 g of polyphosphoric acid [105%]

10.21 g HN0 ₃ [65%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Example 30

Preparation: 200 g graphite (UF 298) [Kropfmühl AG]

1595 g of polyphosphoric acid [105%]

Procedure: First, the graphite was in a 3000ml jacketed vessel with

Anchor stirrer filled and rinsed well (at least 30 min) with nitrogen. Subsequently, the phosphoric acid and then the nitric acid was added and heated to Ti _nn = 30 ° C with stirring (about 160 U / min and nitrogen purge). After a test run time of 5 hours at 30 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

Post-treatment: Half of the residual moisture modified graphite was in a

Glass tube with POR 4 frit on the bottom filled with NH ₃ flows from bottom to top. The other half was heated in a rotary ball flask made of Duranglas under N ₂ and only then flows through in the same manner as the first half with NH ₃ .

Heating program: With 57 min was heated to 300 ° C, held 300 ° C for 120 min and then cooled to room temperature. Example 31

Preparation: 5.40 g graphite (ES 350 F5) [Kropfmühl AG]

32.02 g of polyphosphoric acid [105%] 32.31 g of HNO ₃ [65%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Example 32

Preparation: 4.02 g graphite (Denka Black 50% comp.)

39.88 g of polyphosphoric acid [105%]

Procedure: First, the graphite was in a 100ml two-necked flask with

Example 33

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

70 g of dimethyl methylphosphonate [AB CR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Filled kneader. Subsequently, the organic P component was added. After a kneader running time of 60 minutes at 80 ° C, the reaction mixture was cooled and then removed.

Example 34

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

35 g of dimethyl methylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Filled kneader. Subsequently, the organic P

Component added. After a kneader running time of 60 minutes At 80 ° C, the reaction mixture was cooled and then removed.

Example 35

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

17.5 g of dimethyl methylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 36

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

70 g of bis (2-ethylhexyl) phosphate [Merck]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 37

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

35 g of bis (2-ethylhexyl) phosphate [Merck]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 38

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

17.5 g of bis (2-ethylhexyl) phosphate [Merck]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Filled kneader. Subsequently, the organic P component was added. After a kneader running time of 60 minutes at 80 ° C, the reaction mixture was cooled and then removed. Example 39

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

70 g of diethylbenzylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 40

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

35 g of diethylbenzylphosphonate [ABCR]

First, the implementation of graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 41

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

17.5 g of diethylbenzylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 42

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

70 g of diethyl ethylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Example 43

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

35 g of diethyl ethylphosphonate [ABCR]

Execution: First, the graphite was in a heated (T _pause n = 80 ° C) 250ml

Filled kneader. Subsequently, the organic P Component added. After a kneader running time of 60 minutes at 80 ° C, the reaction mixture was cooled and then removed.

Example 44

Preparation: 70 g graphite (ES 350 F5) [Kropfmühl AG]

17.5 g of diethyl ethylphosphonate [ABCR]

Example 45

Preparation: 600 g graphite (ES 350 F5) [Kropfmühl AG]

1950 ml of dimethyl metylphosphonate [ABCR] about 80 mg of triethyl borate [Merck]

Procedure: First, the graphite was in a 3000ml jacketed vessel with

Anchor stirrer filled, and well rinsed (at least 30 min) with nitrogen. Subsequently, the organic P-component was added, and then, with stirring (160 rev / min and a nitrogen purge) was heated to T = 80 ° C _hold n. After a test run time of 5 hours at 80 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

After treatment: Of the only remaining damp graphite 300g in one

Rotary ball flask made of Duranglas (mass 150 - 200g) filled and then heated under air. The remaining 300 g of residual moist graphite were additionally baked in the same flask with triethyl borate (140 g graphite with 40 g triethyl borate).

Heating program: The system was heated to 250 ° C in 60 minutes, for 120 minutes at

Kept 250 ° C and then cooled.

Example 46

Preparation: 500 g graphite (ES 350 F5) [Kropfmühl AG]

1800 ml of dimethylmetyl phosphonate [ABCR]

Procedure: First, the graphite was in a 3000ml jacketed vessel with

Anchor stirrer filled, and well rinsed (at least 30 min) with nitrogen. Subsequently, the organic P-component was added, and then, with stirring (160 rev / min and a nitrogen purge) was heated to T = 80 ° C _hold n. After a trial period After 5 hours at 80 ° C, the reaction mixture was cooled and then filtered with suction through a glass suction filter (POR 4).

After treatment: Of the only remaining wet graphite were 100g each in one

Rotary ball flask made of Duranglas (mass 150 - 200g) filled and then heated under air, (possibly with additives)

Example 46 A without additional component

Example 46 B with 24g piperazine [Merck]

Example 46 C with 50g TEOS [Alfa Aesar]

Example 46 D with 50 g of triethylamine [Aldrich]

Example 46 H with 100g TEOS [Alfa Aesar]

Kept 250 ° C and then cooled.

Example 47

Preparation: 300 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1000 ml of diethyl ethylphosphonate (98%) [ABCR]

Triethylborate [Merck]

Procedure: The expandable graphite was poured into a 3000 ml jacketed vessel with anchor stirrer and thoroughly purged with nitrogen (at least 30 min). This was followed by the addition of the organic P component. Thereafter, the suspension was heated to T _inne n = 80 ° C with stirring (160 U / min and nitrogen purge) and _held at 80 ° C for 5 hours. The suspension was then cooled to room temperature and then filtered with suction through a glass suction filter (POR 4).

Post-treatment: The resulting, still residual wet modified expandable graphite was placed in a rotary ball flask made of Duranglas (mass 150-200g), treated with triethyl borate (eg 140g graphite with 40g triethyl borate) and then heated under N ₂ .

Heating program: The system was heated to 270 ° C in 60 minutes, at 120 minutes at

Held 270 ° C and then cooled to room temperature.

Example 48

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

1950 ml of dimethyl methylphosphonate [ABCR]

Procedure The expanded graphite was placed in a 3000 ml jacketed vessel with anchor stirrer, which was then thoroughly purged with nitrogen (at least 30 min). After addition of the organic P component (nitrogen atmosphere), the suspension obtained was stirred under Ren (160 rev / min and nitrogen purge) to T _inne n = 80 ° C heated and stirred for 5 hours at 80 ° C. The reaction mixture was then cooled again to room temperature and the modified expandable graphite was separated off via a glass suction funnel (POR 4).

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150 - 200g) filled and then baked under N ₂ .

Example 49

Preparation: 600 g of expandable graphite (ES 350 F5) [Kropfmühl AG]

After treatment: The still residual modified expanded graphite was in a

Rotary ball flask made of Duranglas (mass 150-200g) filled with Triethylborat added (eg 140g graphite with 40g triethyl borate) and then heated under N ₂ .

Production of molding compounds and shaped articles:

To determine the fire characteristics mentioned in the tables below, PA66 and PBT (precompounded with the glass fibers) were homogenized with the functionalized expandable graphite intercalation compound on a DSM Midiextruder and injection molded at 270 ° C (PBT) or 300 ° C (PA66 ) Melt temperature and 170 ° C (PBT) or 180 ° C (PA66) mold surface temperature to test specimens according to UL 94, vertical burning standard, extruded with a thickness of 1, 6 mm / 0.8 mm. Investigation of flame retardancy on a PA 66 Composite

The PA66 reference sample with a glass fiber content of 26% by weight has a molecular weight of 74000 g / mol.

Expanded graphite as such can not be compounded in PA66 since PA66 is processed at temperatures of approx. 300 ° C and simple expandable graphite already begins to expand at these temperatures.

thickness

Wt .-%

Wt% P-UL-94 of M _w

Polymer P-mod.

Glass fibers mod. Graphite Brand Test Rods (g / mol)

graphite

(Mm)

PA66 26 Example 4 5 V2 1 .6 59 000

PA66 26 Example 4 10 VO 1 .6 54 000

PA66 26 Example 4 15 VO 1 .6 48 500

PA66 26 Example 4 20 VO 1 .6 37 400

PA66 - Example 4 5 V2 1 .6 72 000

PA66 - Example 4 10 V2 1 .6 66 000

PA66 - Example 4 15 V2 1 .6 58 000

PA66 - Example 4 20 V2 1 .6 52 000

PA66 26 Example 4 5 V2 0.8 -

PA66 26 Example 4 10 V2 0.8 -

PA66 26 Example 4 15 VO 0.8 -

PA66 - Example 4 5 V2 0.8 -

PA66 - Example 4 10 V2 0.8 -

PA66 - Example 4 15 VO 0.8 -

PA66 26 Example 9 5 V2 0.8 62 000

PA66 26 Example 9 10 VO 0.8 45 600

PA66 26 Example 9 15 VO 0.8 38 300

PA66 26 Example 45 5 V2 0.8 64 000

PA66 26 Example 45 10 VO 0.8 51 000

PA66 26 Example 45 15 VO 0.8 42 600

PA66 26 Example 19 5 V2 0.8 59 000

PA66 26 Example 19 10 V2 0.8 52 000

PA66 26 Example 19 15 VO 0.8 44 400

PA66 26 Example 47 5 VO 0.8 68 000 PA66 26 Example 47 10 VO 0.8 56 000

PA66 26 Example 47 15 VO 0.8 45 200

PA66 26 Example 1 1 5 V2 0.8 57 000

PA66 26 Example 1 1 10 V2 0.8 45 900

PA66 26 Example 1 1 15 VO 0.8 45 000

PA66 26 Example 46 c 5 V2 0.8 62 000

PA66 26 Example 46 c 10 VO 0.8 64 000

PA66 26 Example 46 c 15 VO 0.8 57 000

PA66 26 Example 46 d 5 VO 0.8 65 000

PA66 26 Example 46 d 10 VO 0.8 50 000

PA66 26 Example 46 d 15 VO 0.8 40 600

PA66 26 Example 46 e 5 V2 0.8 -

PA66 26 Example 46 e 10 VO 0.8 -

PA66 26 Example 46 e 15 VO 0.8 -

Investigation of flame retardancy on a PBT composite

The PBT reference sample with a glass fiber content of 25 wt .-% has a molecular weight of 63000 g / mol.

As reference experiments, 5, 10 and 15% of expandable graphite were compounded in PBT, and the injection-molded rods were subjected to the UL-94 test. In all cases at least one V2 classification was achieved.

thickness

Wt .-%

Wt% P-UL-94 of M _w

Polymer P-mod.

Glass fibers mod. Graphite Brand Test Rods (g / mol)

graphite

(Mm)

PBT 25 Example 15 5 VO 1 .6 -

PBT 25 Example 15 10 VO 1 .6 -

PBT 25 Example 15 15 VO 1 .6 -

PBT 25 Example 4 5 VO 1 .6 -

PBT 25 Example 4 10 VO 1 .6 -

PBT 25 Example 4 15 VO 1 .6 - PBT 25 Example 4 5 V2 0.8 29 200

PBT 25 Example 4 10 VO 0.8 25 800

PBT 25 Example 4 15 VO 0.8 21 800

PBT 25 Example 45 5 V2 0.8 30 700

PBT 25 Example 45 10 VO 0.8 27 300

PBT 25 Example 45 15 VO 0.8 21 500

PBT 25 Example 45 5 V2 0.8 28 500

PBT 25 Example 45 10 V2 0.8 23 300

PBT 25 Example 45 15 VO 0.8 17 100

PBT 25 Example 4 5 V2 0.8 24 500

PBT 25 Example 4 10 V2 0.8 20 200

PBT 25 Example 4 15 VO 0.8 12 000

PBT 25 Example 20 5 V2 0.8 29 200

PBT 25 Example 20 10 V2 0.8 25 700

PBT 25 Example 20 15 V2 0.8 16 800

PBT 25 Example 46 d 5 V2 0.8 38 900

PBT 25 Example 46 d 10 VO 0.8 22 200

PBT 25 Example 46 d 15 VO 0.8 17 400

PBT 25 Example 46 e 5 V2 0.8 -

PBT 25 Example 46 e 10 V2 0.8 -

PBT 25 Example 46 e 15 VO 0.8 -

PBT 25 Example 46 b 5 V2 0.8 49 000

PBT 25 Example 46 b 10 V2 0.8 46 800

PBT 25 Example 46 b 15 VO 0.8 40 700

PBT 25 Example 46 c 5 V2 0.8 29 900

PBT 25 Example 46 c 10 V2 0.8 21 900

PBT 25 Example 46 c 15 VO 0.8 15 800 Investigation of the flame retardancy of ABS

Preparation of the molding compositions and moldings: To determine the fire properties mentioned in the table below, the components A) to D) (respective wt .-% e see table) were homogenized on a DSM Midiextruder and with an injection molding attachment at 240 ° C melt temperature and 80 ° C Mold surface temperature to test specimens according to UL 94, vertical burning standard, extruded with a thickness of 1.6 mm.

Afterburn time t _N [s]:

In the fire test based on UL 94, vertical burning standard, the first afterburner time t1 was measured on bars with a thickness of 1.6 mm after a first flame duration of 10 seconds. After a second flame duration of 10 seconds following extinguishment of the flames after 2 seconds, the second afterburn time t2 was measured. The sum of the afterburning times t1 and t2 gives the afterburning time t _N (indicated in each case is the average of the afterburning times determined on two bars).

As components (A) used was: al: A commercially available acrylonitrile-butadiene-styrene copolymer (ABS), Terluran ^®, BASF SE, containing a styrene-acrylonitrile copolymer hard phase and a particle-kelförmigen butadiene graft rubber.

Flame retardant component B):

As component B1) was used:

b1-l: expandable graphite Nord- ^Min® 503 from Nordmann, Rassmann, GmbH, with an average particle size D ₅₀ of 465 μm, a free expansion (starting at about 300 ° C.) of at least 150 ml / g and a bulk density of 0.5 g / ml at 20 ° C. As component B2) was used: b2-l: phosphorus-modified expandable graphite (EG-H-89-1)

b2-ll: phosphorus-modified expanded graphite (EG-H-89-2)

b2-lll: phosphorus-modified expanded graphite (EG-H-88B)

As component B3) was used: b3-l: polytetrafluoroethylene PTFE TE-3893, ^Teflon® dispersion from the company CH Erbslöh with a PTFE content of 60 wt .-% (based on the total weight of the dispersion).

Composition and properties of molding compounds (prefixed V: for comparison)

Example V-1 2 3 4

Composition [parts by weight]

al 84.6 84.6 84.6 84.6 b1 -l15 - - - b2-l - 15 - - b2-ll - - 15 - b2-lll - - - 15 b3-l 0.4 0.4 0.4 0.4

Afterburning time t-1 [s]> 50 1, 1 1, 4 3,6

Afterburn time t ₂ [s] - 2.6 3.2 2.7

Afterburn time t _N [s]> 50 3.7 4.7 6.3

Claims

claims

A process for preparing a functionalized expandable graphite intercalation compound

(a) providing graphite,

(B) reacting the graphite with at least one oxidizing agent in the presence of at least one phosphorus-containing flame retardant compound with intimate mixing.

, H ₃ P0 _4, KMn0 _4, hydrogen peroxide, is nitric acid, sulfuric acid and persulfuric acid method according to claim 1, wherein the at least one oxidizing agent selected from the group of concentrated hydrochloric acid, KCL0. ₄

A method according to claim 1 or 2, wherein the mixture of oxidizing agent and phosphorus-containing flame retardant compound is used in an amount of 1 to 200 parts by weight based on 10 parts by weight of graphite.

(e) providing expandable graphite,

(F) reacting the expandable graphite with at least one phosphorus-containing flameproofing compound with intimate mixing of the expandable graphite with the at least one phosphorus-containing flameproofing compound.

Method according to one of claims 1 to 4, wherein the intimate mixing in process step (b) or (f) is carried out in at least one kneader, mixer or stirred tank.

Method according to one of claims 1 to 5, wherein subsequent to process step (b) or (f), the functionalized expandable graphite intercalation compound in a further process step (g) is filtered.

The method of claim 6, wherein the filtration in step (g) is performed in at least one belt filter, a centrifuge, a suction filter, or a filter press.

8. The method according to any one of claims 1 to 7, wherein subsequent to process step (b) or (f) or subsequent to process step (g), the functionalized expandable graphite intercalation compound in a further process step (h) is dried.

9. The method of claim 8, wherein the drying in step (h) in a fluidized bed dryer, Pastenmahltrockner, thin-layer dryer, current dryer, belt dryer, contact dryer, spray dryer, furnace, rotary kiln, mixing dryer, paddle dryer, conical screw dryer, tumble dryer, drying oven or tumble dryer is performed.

A method according to any one of claims 8 or 9, wherein the drying is carried out at a temperature in the range of 150 to 350 ° C for a period of 1 to 300 minutes.

Method according to one of claims 8 to 1 1, wherein the functionalized graphite intercalation compound before or during drying one or more additives selected from the group of ammonia, boric acid, boric acid derivatives, boronic acid, di- and trialkyl, siloxanes, mono-, di-, tri - And tetraalkoxysilanes, linear and cyclic amines, diamines, polyamines, triethylamine, melamine, metal oxides such as zinc, titanium and magnesium oxide, alkali metal, magnesium and aluminum hydroxide may be added.

12. Functionalized expandable graphite intercalation compound obtainable by a process according to one of claims 1 to 11.