EP1309655A1

EP1309655A1 - Flame-resistant polycarbonate compositions

Info

Publication number: EP1309655A1
Application number: EP01960495A
Authority: EP
Inventors: Thomas Eckel; Nikolaus Janke; Uwe Peucker; Andreas Seidel; Dieter Wittmann
Original assignee: Bayer AG
Current assignee: Covestro Deutschland AG
Priority date: 2000-07-25
Filing date: 2001-07-12
Publication date: 2003-05-14
Also published as: TW548306B; CN1444625A; US20020147256A1; DE10036057A1; KR20030020408A; WO2002008329A1; CA2416875A1; AU2001281978A1; JP2004504466A; BR0112700A; MXPA03000687A

Abstract

The invention relates to flame-resistant polycarbonate compositions containing a phosphorus compound of formula (I) wherein Y represents isopropylidene, wherein the composition content of isopropyl phenyl phosphate is less than 1 % wt in relation to mass of the phosphorus compound thus used. The inventive compositions have excellent flame-resistant and very good mechanical properties in addition to possessing a high heat defelection point.

Description

Flame retardant polycarbonate compositions

The invention relates to flame-retardant polycarbonate compositions containing phosphate compounds and moldings produced therefrom.

The use of diphosphates as flame retardants for polycarbonate compositions is known and is described, for example, in EP-A 0 363 608, EP-A 0771 851 and EP-A 0 755 977. The associated deterioration is problematic when using diphosphates as flame retardants the mechanical

Properties of the polycarbonate. In order to achieve a balanced property profile, other additives must therefore usually be added.

For certain applications that require a particularly high hydrolysis stability or are allowed to form very little tool coating due to the tool design, oligophosphates based on bisphenol-A are used as flame retardants.

WO 99/07792 discloses flame-retardant polycarbonate ABS compositions which contain an additive combination of an oligophosphate based on bisphenol-A and a synergistically effective amount of one or more finely divided inorganic materials in order to improve the resistance to stress cracking, impact resistance and heat resistance.

DE-A 198 53 105 also discloses flame-retardant, graft polymer-modified polycarbonate compositions which contain oligophosphates on bisphenol-A and special graft polymers obtainable by bulk polymerization in order to improve the mechanical properties.

A disadvantage of these polycarbonate compositions is, in particular, that the molded articles produced therefrom have a permanent thermal stress experienced increasing deterioration in mechanical properties. In addition, there is a tendency to yellowing when stored under heat, which is undesirable for technical and aesthetic reasons.

The object of the invention is to provide flame-retardant polycarbonate compositions which, in addition to good mechanical properties and high heat resistance, have significantly improved long-term behavior (preservation of properties under thermal stress).

It has now been found that polycarbonate compositions which contain special phosphorus compounds with a low content of isopropenylphenylphosphate, <1% by weight, based on the phosphorus compound used, have the desired profile of properties.

Commercial bisphenol A based oligophosphates contain isopropenylphenyl phosphate (IPP) as an impurity in an amount of up to about 10% by weight. This contamination arises as a fission product in the synthesis of the oligophosphates mentioned, in particular at high temperature and a long reactor residence time. In addition, the fission product can also form as a result of improper transport and / or storage.

Surprisingly, it was found that isopropenylphenyl phosphate contained as an impurity in commercially available bisphenol A-based oligophosphates has an unfavorable effect on the properties of the polycarbonates or polyester carbonates treated with the oligophosphates as flame retardants. An excessively high IPP content has a particularly unfavorable effect on the afterburn time, measured in accordance with UL 94, and on the heat resistance. Furthermore, too high an IPP content leads to prolonged thermal loads or heat storage, which can occur in certain applications, e.g. B. 1500 hours at 60 ° C or 500 hours at 80 ° C, to a yellowing of the polycarbonate

Compositions or poorer mechanical properties. According to the invention, these disadvantages are avoided by limiting the IPP content of the oligophosphate used as flame retardant to less than 1% by weight. Polycarbonates or polyester carbonates finished with such a flame retardant have improved heat resistance, improved afterburning behavior and less tendency to yellowing when stored under heat.

The invention therefore relates to polycarbonate compositions, in particular thermoplastic polycarbonate compositions, containing phosphorus compounds of the formula (I)

wherein

R ⁱ , R ^, R3 and R ^, independently of one another optionally halogen-substituted C to Cg-alkyl, each optionally halogen-substituted and / or alkyl-substituted C5 to Cß-cycloalkyl, C to CiQ-Nryl or C7 to C12 aralkyl,

n independently of one another 0 or 1,

q independently of one another 0, 1, 2, 3 or 4,

N is 0.1 to 5, preferably 0.9 to 2.5, in particular 1 to 1.5, 5 and R6 independently of one another are C to C4-alkyl, preferably methyl or halogen, preferably chlorine and / or bromine,

Y is isopropylidene and

wherein the composition has an isopropenylphenyl phosphate content of less than 1% by weight, preferably less than 0.5% by weight, particularly preferably less than 0.2% by weight, based on the weight of the phosphorus compound used.

The compositions preferably contain 0.5 to 20, particularly preferably 1 to 18 and in particular 2 to 16% by weight of phosphorus compound (I) or a mixture of phosphorus compounds (I).

Compositions containing are preferred

A) 40 to 99 wt .-%, preferably 50 to 95 wt .-%, in particular 60 to 90 wt .-% aromatic polycarbonate and / or polyester carbonate

B) 0.5 to 60% by weight, preferably 0.8 to 40% by weight, in particular 1 to

30% by weight of graft polymer

C) 0 to 45% by weight of at least one thermoplastic polymer selected from the group consisting of vinyl (co) polymers and polyalkylene terephthalates,

D) 0.5 to 20% by weight of phosphorus compound of the general formula (I)

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , Y, N and n have the meaning given above and

E) 0 to 5% by weight of fluorinated polyolefin,

where the amounts of the components add up to 100.

Components A (polycarbonate or polyester carbonate), B (graft polymer), C (copolymer), D (phosphorus compound), E (fluorinated polyolefins) suitable for producing the compositions according to the invention are described in more detail below.

Component A

Aromatic polycarbonates and / or aromatic polyester carbonates according to component A which are suitable according to the invention are known from the literature or can be prepared by processes known from the literature (for the preparation of aromatic polycarbonates, see, for example, Schnell, "Chemistry and Physics of Polycarbonates", Interscience Publishers, 1964 and DE-A 14 95 626, DE-A 22 32 877, DE-A 27 03 376, DE-A 27 14 544, DE-A 30 00 610, DE-A 38 32 396; for the production of aromatic polyester carbonates e.g. DE-A 30 77 934.

Aromatic polycarbonates are prepared, for example, by reacting diphenols with carbonic acid halides, preferably phosgene, and / or with aromatic dicarboxylic acid dihalides, preferably benzenedicarboxylic acid di halides, by the phase interface method, if appropriate using chain terminators, for example monophenols, and if appropriate using trifunctional or more than functional branching agents, for example triphenols or tetraphenols.

Diphenols for the preparation of the aromatic polycarbonates and / or aromatic polyester carbonates are preferably those of the formula (II)

in which

a single bond, Ci to C5-alkylene, C2 to C5-alkylidene, C5 to Cg-cycloalkylidene, -O-, -SO-, -CO-, -S-, -SO ₂ -, Cg to Ci2-arylene, to the further aromatic rings optionally containing heteroatoms can be condensed,

or a radical of the formula (m) or (TV)

B each C to C 2 alkyl, preferably methyl, halogen, preferably chlorine and / or bromine

x each independently of one another 0, 1 or 2,

p are 1 or 0, and

R and R8 can be selected individually for each oil, independently of one another hydrogen or C to C6-alkyl, preferably hydrogen, methyl or ethyl,

X ¹ carbon and

m is an integer from 4 to 7, preferably 4 or 5, with the proviso that at least one atom χl, R ^ and ltß are simultaneously alkyl.

Preferred diphenols are hydroquinone, resorcinol, dihydroxydiphenols, bis (hydroxyphenyι) -C -C5 alkanes, bis (hydroxyphenyl) -C5-C6 cycloalkanes, bis (hydroxyphenyl) ether, bis (hydroxyphenyl) sulfoxides, bis - (Hydroxyphenyl) ketones, bis (hydroxyphenyl) sulfones and α, α-bis (hydroxyphenyl) diisopropyl benzenes and their core-brominated and / or core-chlorinated derivatives.

Particularly preferred diphenols are 4,4'-dihydroxydiphenyl, bisphenol-A, 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis- (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 4,4'-dihydroxydiphenyl sulfide,

4,4'-dihydroxydiphenyl sulfone and their di- and tetrabrominated or chlorinated derivatives such as 2,2-bis (3-chloro-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4 -hydroxyphenyl) propane or 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane.

2,2-bis (4-hydroxyphenyl) propane (bisphenol-A) is particularly preferred. The diphenols can be used individually or as any mixtures and are known from the literature or can be obtained by processes known from the literature.

Suitable chain terminators for the production of the thermoplastic, aromatic polycarbonates are, for example, phenol, p-chlorophenol, p-tert-butylphenol or 2,4,6-tribromophenol, but also long-chain alkylphenols, such as 4- (1,3-tetramethylbutyl) -phenol according to DE-A 28 42 005 or monoalkylphenol or dialkylphenols with a total of 8 to 20 carbon atoms in the alkyl substituents, such as 3,5-di-tert-butylphenol, p-iso-octylphenol, p-tert. -Octylphenol, p-dodecylphenol and 2- (3,5-dimethylheptyl) phenol and 4- (3,5-dimethylheptyl) phenol. The amount of chain terminators to be used is generally between 0.5 mol% and 10 mol%, based on the molar sum of the diphenols used in each case.

The thermoplastic, aromatic polycarbonates have average weight-average molecular weights M _w , for example measured by ultracentrifuge or scattered light measurement, of 10,000 to 200,000, preferably 20,000 to 80,000.

The thermoplastic, aromatic polycarbonates can be branched in a known manner, preferably by incorporating 0.05 to 2.0 mol%, based on the sum of the diphenols used, of trifunctional or more than non-functional compounds, for example those with three and more phenolic groups.

Both homopolycarbonates and copolycarbonates are suitable. For the preparation of copolycarbonates according to component A to be used according to the invention, 1 to 25% by weight, preferably 2.5 to 25% by weight, based on the total amount of diphenols to be used, polydiorganosiloxanes with hydroxyaryloxy end groups can also be used. These are known, for example, from US 3,419,634 or can be produced by methods known from the literature. The Production of copolycarbonates containing polydiorganosiloxane is described, for example, in DE 33 34 782.

In addition to the bisphenol A homopolycarbonates, preferred polycarbonates are the copolycarbonates of bisphenol A with up to 15 mol%, based on the molar sum of diphenol, of other diphenols, in particular 2,2-bis (3, 5-dibromo-4-hydroxyphenyl) propane.

Aromatic dicarboxylic acid dihalides for the production of aromatic polyester carbonates are preferably the diacid dichlorides of isophthalic acid,

Terephthalic acid, diphenyl ether-4,4'-dicarboxylic acid and naphthalene-2,6-dicarboxylic acid.

Mixtures of the diacid dichlorides of isophthalic acid and terephthalic acid in a ratio between 1:20 and 20: 1 are particularly preferred.

In the production of polyester carbonates, a carbonic acid halide, preferably phosgene, is additionally used as the bifunctional acid derivative.

In addition to the monophenols already mentioned, the chain terminators for the preparation of the aromatic polyester carbonates are their chlorocarbonic acid esters and the acid chlorides of aromatic monocarboxylic acids, which may be substituted by C ₁ -C ₂₂ -alkyl groups or by halogen atoms, and aliphatic C ₂ -C ₂₂ -monocarboxylic acid chlorides into consideration.

The amount of chain terminators is preferably 0.1 to 10 mol%, based on the mol of diphenol in the case of the phenolic chain terminators and on the mol of dicarboxylic acid dichloride in the case of monocarboxylic acid chloride chain terminators.

The aromatic polyester carbonates can also contain built-in aromatic hydroxycarboxylic acids. The aromatic polyester carbonates can be either linear or branched in a known manner, in this respect reference is made to the disclosure of DE-A 29 40 024 and DE-A 30 07 934.

Examples of branching agents which can be used are 3- or polyfunctional carboxylic acid chlorides, such as trimesmic acid trichloride, cyanuric acid trichloride, 3,3 '-, 4,4'-benzophenonetetracarboxylic acid tetrachloride, 1, 4,5,8-naphthalenetetracarboxylic acid tetrachloride or pyromelththalic acid tetrachloride, in quantities of 0.01 up to 1.0 mol% (based on the dicarboxylic acid dichlorides used) or 3- or polyfunctional phenols such as chloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -hepten-2, 4,4-dimethyl-2,4-6-tri- (4-hydroxyphenyl) heptane, 1,3,5-tri- (4-hydroxyphenyl) benzene, 1,1,1-tri- (4-hy - hydroxyphenyl) ethane, tri- (4-hydroxyphenyl) phenylmethane, 2,2-bis [4,4-bis (4-hydroxyphenyl) cyclohexyl] propane, 2,4-bis (4- hydroxyphenyl-isopropyl) phenol, tetra- (4-hydroxyphenyl) methane, 2,6-bis (2-hydroxy-5-methyl-benzyl) -4-methylphenol, 2- (4-hydroxyphenyl) -2- (2,4-dihydroxyphenyl) propane, tetra- (4- [4-hydroxyphenylisopropyl] phenoxy) methane, 1,4-bis [4,4'-dihydroxytriphenyl) methyl] benzene, in Quantities of 0.0 1 to 1.0 mol%, based on the diphenol used. Phenolic branching agents can be introduced with the diphenols, acid chloride branching agents can be introduced together with the acid dichlorides.

The proportion of carbonate structural units in the thermoplastic, aromatic polyester carbonates can vary as desired. The proportion of carbonate groups is preferably up to 100 mol%, in particular up to 80 mol%, particularly preferably up to 50 mol%, based on the sum of ester groups and carbonate groups. Both the ester and the carbonate content of the aromatic polyester carbonates can be present in the form of blocks or randomly distributed in the polycondensate. The relative solution viscosity (η _re ι) of the aromatic polycarbonates and polyester carbonates is 1.18 to 1.4, preferably 1.2 to 1.3, measured on solutions of 0.5 g polycarbonate or polyester carbonate in 100 ml methylene chloride at 25 ° C.

The thermoplastic, aromatic polycarbonates and polyester carbonates can be used alone or in any mixture with one another.

Component B

Graft polymers B which can be used according to the invention include, for example Graft copolymers with rubber-elastic properties, which are essentially obtainable from at least two of the following monomers: chloroprene, 1,3-butadiene, isopropene, styrene, acrylonitrile, ethylene, propylene, vinyl acetate and (meth) -acrylic acid esters with 1 to 18 Carbon atoms in the alcohol component; i.e. polymers such as in "Methods of Organic Chemistry" (Houben-Weyl), Vol. 14/1, Georg

Thieme-Veriag, Stuttgart 1961, pp. 393-406 and in C.B. Bucknall, "Thoughened Plastics", Appl. Science Publishers, London 1977. Preferred polymers C are partially crosslinked and have gel contents of over 20% by weight, preferably over 40% by weight, in particular over 60% by weight ,

In particular, component B comprises one or more graft polymers of

B.l 5 to 95, preferably 30 to 90 wt .-%, of at least one vinyl monomer

B.2 95 to 5, preferably 70 to 10% by weight of one or more graft bases with glass transition temperatures <10 ° C, preferably <0 ° C, particularly preferably <-20 ° C. The graft base B.2 has, in general, an average particle size (d ₅ o-value) of 0.05 to 5 μ, preferably from 0.10 microns to 0.6, particularly preferably 0.1 to 0.5, most preferably 0 , 20 to 0.40 µm.

Monomers B.l are preferably mixtures of

B.l.l 50 to 99 parts by weight of vinyl aromatics and / or nucleus-substituted

Vinyl aromatics (such as styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene) and / or (with acrylic acid to C ₈ ) alkyl esters (such as methyl methacrylate, ethyl methacrylate) and

B12 1 to 50 parts by weight of vinyl cyanides (unsaturated nitriles such as acrylonitrile and methacrylonitrile) and / or (Met ^ acrylic acid ^ _! To C ₈ ) - alkyl esters (such as methyl methacrylate, n-butyl acrylate, t-butyl acrylate) and / or Derivatives (such as anhydrides and imides) of unsaturated carboxylic acids (for example maleic anhydride and N-phenyl-maleimide).

Preferred monomers B.l.l are selected from at least one of the monomers styrene, α-methylstyrene and methyl methacrylate, preferred monomers B.l.2 are selected from at least one of the monomers acrylonitrile, maleic anhydride and methyl methacrylate.

Particularly preferred monomers are styrene (B.l.l) and acrylonitrile (B.l.2).

Graft bases B.2 suitable for the graft polymers B are, for example, diene rubbers, EP (D) M rubbers, that is to say those based on ethylene / propylene and, if appropriate, diene, acrylate, polyurethane, silicone, chloroprene and ethylene / vinyl acetate rubbers. Preferred graft bases B.2 are diene rubbers (e.g. based on butadiene, isoprene etc.) or mixtures of diene rubbers or copolymers of diene rubbers or their mixtures with other copolymerizable monomers (for example according to B1 and B1), with the proviso that the glass transition temperature component B.2 below <10 ° C, preferably <0 ° C, particularly preferred

<-10 ° C.

Pure polybutadiene rubber is particularly preferred.

Particularly preferred polymers B are e.g. ABS polymers (emulsion,

Mass and suspension ABS), e.g. are described in DE-A 20 35 390 or DE-A 22 48 242 or in Ullmann, Enzyklopadie der Technischen Chemie, Vol. 19 (1980), p. 280 ff. The gel fraction of the graft base B.2 is preferably at least 30% by weight, preferably at least 40% by weight (measured in toluene).

The graft copolymers B are obtained by radical polymerization, e.g. prepared by emulsion, suspension, solution or bulk polymerization, preferably by emulsion polymerization or bulk polymerization.

ABS polymers which are produced by redox initiation with an initiator system of organic hydroperoxide, cumene hydroperoxide or t-butyl hydroperoxide and ascorbic acid, according to US Pat. No. 4,937,285, are also particularly suitable graft rubbers.

Since, as is well known, the graft monomers are not necessarily grafted completely onto the graft base in the graft reaction, graft polymers B are also understood according to the invention to mean those products which are obtained by (co) polymerizing the graft monomers in the presence of the graft base and are also obtained in the working up. Suitable acrylate rubbers according to B.2 of the polymers B are preferably polymers of alkyl acrylates, optionally with up to 40% by weight, based on B.2, of other polymerizable, ethylenically unsaturated monomers. The preferred polymerizable acrylic acid esters include C 1 -C ₈ -alkyl esters, for example methyl, ethyl, butyl, n-octyl and 2-ethylhexyl esters; Halogen alkyl esters, preferably halogen CrCs alkyl esters, such as chloroethyl acrylate and mixtures of these monomers.

For crosslinking, monomers can be copolymerized with more than one polymerizable double bond. Preferred examples of crosslinking monomers are

Esters of unsaturated monocarboxylic acids with 3 to 8 C atoms and unsaturated monohydric alcohols with 3 to 12 C atoms, or saturated polyols with 2 to 4 OH groups and 2 to 20 C atoms, such as ethylene glycol dimethacrylate, allyl methacrylate; polyunsaturated heterocyclic compounds such as trivinyl and triallyl cyanate; polyfunctional vinyl compounds such as di- and trivinylbenzenes; but also

Triallyl phosphate and diallyl phthalate.

Preferred crosslinking monomers are allyl methacrylate, ethylene glycol dimethacrylate, diallyl phthalate and heterocyclic compounds which have at least three ethylenically unsaturated groups.

Particularly preferred crosslinking monomers are the cyclic monomers trialyll cyanurate, triallyl isocyanurate, triacryloylhexahydro-s-triazine and triallylbenzenes. The amount of the crosslinked monomers is preferably 0.02 to 5, in particular 0.05 to 2% by weight, based on the graft base B.2.

In the case of cyclic crosslinking monomers with at least three ethylenically unsaturated groups, it is advantageous to limit the amount to below 1% by weight of the graft base B.2. Preferred "other" polymerizable, ethylenically unsaturated monomers which, in addition to the acrylic acid esters, can optionally be used to prepare the graft base B.2 are, for. B. acrylonitrile, styrene, α-methylstyrene, acrylamides, vinyl-Cr C ₆ -alkyl ether, methyl methacrylate, butadiene. Preferred acrylate rubbers as graft base B.2 are emulsion polymers which have a gel content of at least 60% by weight.

Further suitable graft bases according to B.2 are silicone rubbers with graft-active sites, as described in DE-A 37 04 657, DE-A 37 04 655, DE-A 36 31 540 and DE-A 36 31 539.

The gel content of the graft base B.2 is determined at 25 ° C. in a suitable solvent (M. Hoffmann, H. Krömer, R. Kuhn, Polymeranalytik I and π, Georg Thieme-Veriag, Stuttgart 1977).

The average particle size d ₅₀ is the diameter above and below which 50% by weight of the particles lie. It can be determined by means of ultracentrifuge measurement (W. Scholtan, H. Lange, Kolloid, Z. and Z. Polymer 250 (1972), 782-1796).

Component C

Component C comprises one or more thermoplastic vinyl (co) polymers C.l and / or polyalkylene terephthalates C.2.

Suitable as vinyl (co) polymers Cl are polymers of at least one monomer from the group of the vinyl aromatics, vinyl cyanides (unsaturated nitriles), (meth) acrylic acid (C ₁ to C ₈ ) alkyl esters, unsaturated carboxylic acids and derivatives (such as anhydrides and imides ) unsaturated carboxylic acids. (Co) polymers of are particularly suitable Cll 50 to 99, preferably 60 to 80 wt .-% vinyl aromatics and / or core-substituted vinyl aromatics such as styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene) and / or (meth) acrylic acid (Ci to C ₈ ) - Alkyl esters such as methyl methacrylate, ethyl methacrylate), and

C.l.2 1 to 50, preferably 20 to 40 wt .-% vinyl cyanide (unsaturated

Nitriles) such as acrylonitrile and methacrylonitrile and / or (meth) acrylic acid (Ci to C ₈ ) alkyl esters (such as methyl methacrylate, n-butyl acrylate, t-butyl acrylate) and / or unsaturated carboxylic acids (such as maleic acid) and / or derivatives ( such as anhydrides and imides) of unsaturated carboxylic acids (for example maleic anhydride and N-phenyl-maleimide).

The (co) polymers C.l are resin-like, thermoplastic and rubber-free.

The copolymer of C.I. 1 styrene and C.I. 2 acrylonitrile is particularly preferred.

The (co) polymers according to Cl are known and can be prepared by radical polymerization, in particular by emulsion, suspension, solution or bulk polymerization. The (co) polymers preferably have molecular weights M _w (weight average, determined by light scattering or sedimentation) between 15,000 and 200,000.

The polyalkylene terephthalates of component C.2 are reaction products of aromatic dicarboxylic acids or their reactive derivatives, such as dimethyl esters or anhydrides, and aliphatic, cycloaliphatic or araliphatic diols and mixtures of these reaction products.

Preferred polyalkylene terephthalates contain at least 80% by weight, preferably at least 90% by weight, based on the dicarboxylic acid component terephthalic acid. residues and at least 80 wt .-%, preferably at least 90 mol%, based on the diol component ethylene glycol and / or 1,4-butanediol residues.

In addition to terephthalic acid residues, the preferred polyalkylene terephthalates can contain up to 20 mol%, preferably up to 10 mol%, of residues of other aromatic or cycloaliphatic dicarboxylic acids with 8 to 14 C atoms or aliphatic dicarboxylic acids with 4 to 12 C atoms, such as residues of phthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, cyclohexanediacetic acid.

In addition to ethylene glycol or butanediol 1,4-residues, the preferred polyalkylene terephthalates can contain up to 20 mol%, preferably up to 10 mol%, other aliphatic diols with 3 to 12 carbon atoms or cycloaliphatic diols with 6 to 21 Contain carbon atoms, e.g. Residues of propanediol-1,3,2-ethylpropanediol-1,3, neopentylglycol, pentanediol-1,5, hexanediol-1,6, cyclohexane-dimethanol-1,4,3-ethylpentanediol-2,4,

2-methylpentanediol-2,4,2,2,4-trimethylpentanediol-1,3,2-ethylhexanediol-1,3,2,2-diethylpropanediol-1,3, hexanediol-2,5,1,4-di- (ß-hydroxyethoxy) benzene, 2,2-bis (4-hydroxycyclohexyl) propane, 2,4-dihydroxy-l, 1, 3,3-tetramethylcyclobutane, 2,2-bis (4-ß-hydroxyethoxyphenyι ) propane and 2,2-bis (4-hydroxypropoxyρhenyl) propane (DE-A 24 07 674, DE-A 24 07 776, DE-A

27 15 932.

The polyalkylene terephthalates can be prepared by incorporating relatively small amounts of trihydric or tetravalent alcohols or trihydric or tetravalent carboxylic acids, e.g. according to DE-A 19 00 270 and US 36 92 744. Examples of preferred branching agents are trimesic acid, trimellitic acid, trimethylolethane and -propane and pentaerythritol.

Polyalkylene terephthalates which consist solely of terephthalic acid and its reactive derivatives (for example its dialkyl esters) and ethylene glycol are particularly preferred and / or 1,4-butanediol, and mixtures of these polyalkylene terephthalates.

Mixtures of polyalkylene terephthalates contain 1 to 50% by weight, preferably 1 to 30% by weight, polyethylene terephthalate and 50 to 99% by weight, preferably 70 to 99% by weight, polybutylene terephthalate.

The polyalkylene terephthalates preferably used generally have an intrinsic viscosity of 0.4 to 1.5 dl / g, preferably 0.5 to 1.2 dl / g, measured in phenol / o-dichlorobenzene (1: 1 parts by weight) at 25 ° C. in the Ubbelohde viscometer.

The polyalkylene terephthalates can be prepared by known methods (see e.g. Kunststoff-Handbuch, Volume VUl, p. 695 ff., Carl-Hanser-Verlag, Munich 1973).

Component D

The compositions according to the invention contain phosphorus compounds of the general formula Q) as flame retardants,

in which the radicals have the meanings given above.

The phosphorus compounds according to component D which are suitable according to the invention are generally known (see, for example, Ullmanns Encyklopadie der Technischen

Chemie, vol. 18, pp. 301 ff. 1979; Houben-Weyl, Methods of Organic Chemistry, Vol. 12/1, p. 43; Beistein, Vol. 6, p. 177). Preferred substituents R ¹ to R ⁴ include methyl, butyl, octyl, chloroethyl, 2-chloropropyl, 2,3-dibromopropyl, phenyl, cresyl, cumyl, naphthyl, chlorophenyl, bromophenyl, pentachlorophenyl and pentabromophenyl. Methyl, ethyl, butyl, phenyl and naphthyl are particularly preferred.

The aromatic groups Rl, R ^, R3 and R ⁴ can be substituted with halogen and / or C to C4-alkyl. Particularly preferred aryl radicals are cresyl, phenyl, xylenyl, propylphenyl or butylphenyl and also the brominated and chlorinated derivatives thereof.

R ^ and R ^Ö independently of one another are preferably methyl or bromine.

Y stands for isopropylidene.

n in formula (I) can be independently 0 or 1, preferably n is 1.

q can be 0, 1, 2, 3 or 4, preferably q is 0, 1 or 2.

N can assume values from 0.1 to 5, preferably 0.9 to 2.5, in particular 1 to 1.5.

Mixtures of different phosphates can also be used as component D according to the invention. In this case, N is an average. In this

Mixtures can also contain monophosphorus compounds other than IPP, such as and preferably triphenyl phosphate, tricreyl phosphate.

The mean N values can be determined using a suitable method (gas chromatography (GC), High Pressure Liquid Chromatography

(HPLC), gel permeation chromatography (GPC)) the composition of the Phosphate mixture (molecular weight distribution) is determined and from this the mean values for N are calculated.

An essential feature of the phosphorus compounds which can be used according to the invention is that they have an isopropenylphenyl phosphate (IPP) content of less than 1% by weight.

%, preferably less than 0.5% by weight, more preferably less than 0.2% by weight. Under certain conditions (high temperature, long reactor residence time), isopropenylphenyl phosphate (IPP) forms as a cleavage product in the synthesis of oligophosphates of the general formula (I). When producing the phosphorus compounds which can be used according to the invention by the processes mentioned in the literature, it is therefore necessary to ensure that the IPP content does not exceed the stated values by suitable reaction procedures (e.g. lower temperature, short catalyst residence time). Otherwise, the isopropenylphenyl phosphate content of the phosphorus compound to be used must be reduced to a value <1% by weight by suitable cleaning or separation processes (e.g. chromatography or extraction with suitable solvents) before it can be used as a flame retardant.

Component E

Fluorinated polyolefins can be added as a further component.

The fluorinated polyolefins E are of high molecular weight and have glass transition temperatures of above -30 ° C., generally above 100 ° C., fluorine contents, preferably from 65 to 76, in particular from 70 to 76% by weight, average particle diameter d ₅₀ of 0, 05 to 1,000, preferably 0.08 to 20 μm. In general, the fluorinated polyolefins E have a density of 1.2 to 2.3 g / cm ³ . Preferred fluorinated polyolefins E are polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene and ethylene / tetrafluoroethylene copolymers. The fluorinated polyolefins are known (cf. "Vinyl and Related Polymers" by Schildknecht, John Wiley &

Sons, Inc., New York, 1962, pages 484-494; "Fluoropolymers" by Wall, Wiley-Inter- science, John Wiley & Sons, Inc., New York, Vol. 13, 1970, pages 623-654; "Modern Plastics Encyclopedia", 1970-1971, volume 47, No. 10A, October 1970, Mc Graw-Hill, Inc., New York, pages 134 and 774; "Modern Plastica Encyclopedia", 1975-1976, October 1975, Vol. 52, No. 10 A, Mc Graw-Hill, Inc., New York, pages 27, 28 and 472 and US 3,671,487, US 3,723,373 and US 3 838 092).

They can be prepared by known processes, for example by polymerizing tetrafluoroethylene in an aqueous medium with a free radical-forming catalyst, for example sodium, potassium or ammonium peroxydisulfate at pressures from 7 to 71 kg / cm ² and at temperatures from 0 to 200 ° C, preferably at temperatures of 20 to 100 ° C, for example described in US 2,393,967. Depending on the form of use, the density of these materials can be between 1.2 and 2.3 g / cm ³ , the average particle size between 0.5 and 1000 μm.

Fluorinated polyolefins E preferred according to the invention are tetrafluoroethylene polymers with average particle diameters of 0.05 to 20 μm, preferably 0.08 to 10 μm, and a density of 1.2 to 1.9 g / cm ³ and are preferably coagulated Mixture of emulsions of tetrafluoroethylene polymers E with emulsions of graft polymers B used. Suitable tetrafluoroethylene polymer emulsions are commercially available products and are offered, for example, by DuPont as Teflon® ^30N .

Suitable fluorinated polyolefins E which can be used in powder form are tefrafluoroethylene polymers with average particle diameters from 100 to 1,000 μm and densities from 2.0 g / cm ³ to 2.3 g / cm ³ and are sold by DuPont as Teflon and Dyneon GmbH , (Burgkirchen, Germany) under the trade name Hostaflon ^® PTFE.

The compositions of the invention can be at least one of the usual

Additives, such as lubricants and mold release agents, for example pentaerythritol tetrastearate, Contain nucleating agents, antistatic agents, stabilizers, fillers and reinforcing materials as well as dyes and pigments.

The polycarbonate composition according to the invention may further contain 0 to 50% by weight of very finely divided inorganic compound with an average particle diameter of less than 200 nm. Such very finely divided inorganic compounds are described, for example, in US Pat. No. 5,849,827.

The filled or reinforced compositions can contain up to 60, preferably 10 to 40% by weight, based on the filled or reinforced composition, fillers and / or reinforcing materials. Preferred reinforcing materials are glass fibers. Preferred fillers, which can also have a reinforcing effect, are glass balls, mica, silicates, quartz, talc, titanium dioxide, wollastonite.

The compositions according to the invention can contain up to 35% by weight, based on the total composition, of a further, optionally synergistic, flame retardant. Examples of other flame retardants are organic halogen compounds such as decabromobisphenyl ether, tetrabromobisphenol, inorganic halogen compounds such as ammonium bromide, nitrogen compounds such as melamine, melamine formaldehyde resins, inorganic hydroxide compounds such as Mg, Al hydroxide, inorganic compounds such as antimony oxides, barium metaborate, hydroxoantimonate and zirconium oxide , Zirconium hydroxide, molybdenum oxide, ammonium molybdate, zinc borate, ammonium borate, barium metaborate, talc, silicate, silicon oxide and tin oxide as well as siloxane compounds. Monophosphate compounds other than IPP, oligomeric phosphate compounds or mixtures thereof can also be used as flame retardants. Such phosphorus compounds are described in EP-A 0 363 608, EP-A 0 345 522 and DE-A 19721 628.

The compositions according to the invention containing components A to E and optionally other known additives such as stabilizers, dyes, Pigments, lubricants and mold release agents, nucleating agents as well as antistatic agents, fillers and reinforcing materials are produced by mixing the respective components in a known manner and melt-compounding them at temperatures of 200 ° C to 300 ° C in conventional units such as internal kneaders, extruders and twin-screw screws and melt extruded, component E preferably being used in the form of the coagulated mixture already mentioned.

The individual constituents can be mixed in a known manner both successively and simultaneously, both at about 20 ° C. (room temperature) and at a higher temperature.

Because of their excellent flame resistance, in particular the short afterburning time, and their good mechanical properties and high heat resistance, the thermoplastic compositions according to the invention are suitable for the production of moldings of all kinds, in particular those with increased demands on mechanical properties, especially when the compositions are longer are exposed to thermal loads.

The compositions of the present invention can be used for the production of moldings of any kind. In particular, moldings can be made through

Injection molding. Examples of moldings that can be produced are: Housing parts of all types, e.g. for household appliances such as juicers, coffee machines, mixers, for office machines such as monitors, printers, copiers or cover plates for the construction sector and parts for the motor vehicle sector. They can also be used in the field of electrical engineering because they have very good electrical properties.

Furthermore, the compositions according to the invention can be used, for example, for the production of the following moldings or moldings:

Interior components for rail vehicles, hubcaps, housings for electrical devices containing small transformers, housings for devices for disseminating information and transmission, housings and cladding for medical purposes, massagers and housings therefor, play vehicles for children, flat wall elements, housings for safety devices, rear spoilers, heat-insulated transport containers, devices for keeping or supplying small animals, molded parts for sanitary and bathing equipment, cover grilles for ventilation openings , Molded parts for garden and tool sheds, housings for garden tools.

Another form of processing is the production of molded articles by deep drawing from previously produced sheets or foils.

The invention is described in more detail below using an exemplary embodiment.

example

Component A

Polycarbonate based on bisphenol A with a relative solution viscosity of 1.255, measured in methylene chloride at 25 ° C and in a concentration of 0.5 g / 100 ml.

Component B

Graft polymer of 40% by weight of a copolymer of styrene and acrylonitrile in a ratio of 73:27 to 60% by weight of particulate crosslinked polybutadiene rubber (average particle diameter d ₅₀ = 0.34 μm), produced by emulsion polymerization.

Component C

Styrene / acrylonitrile copolymer with a styrene / acrylonitrile ratio of 72:28 and an intrinsic viscosity of 0.55 dl / g (measurement in dimethylformamide at 20 ° C).

Component D

Dl N = l, l; IPP content: 0.1% by weight of D.2 N = 1.1; IPP content: 9.0% by weight To determine the average N value, the proportions of the monomeric and oligomeric phosphates are first determined by HPLC measurements:

Column type: LiChrosorp RP-8 eluent in the gradient:

Acetonitrile / water 50:50 to 100: 0 concentration 5 mg / ml

The number-weighted mean values are then calculated from the proportions of the individual components mono- and oligophosphates using known methods.

The IPP content of the oligophosphate was also determined by the HPLC measurement described above.

Component E

Tetrafluoroethylene polymer as a coagulated mixture of a SAN graft polymer emulsion according to component B in water and a tetrafluoroethylene polymer emulsion in water. The weight ratio of graft polymer B to tetrafluoroethylene polymer E in the mixture is 90% by weight to 10% by weight. The

Tetrafluoroethylene polymer emulsion has a solids content of 60% by weight, the average particle diameter is between 0.05 and 0.5 μm. The SAN graft polymer emulsion has a solids content of 34% by weight and an average latex particle diameter of 0.34 μm.

For the preparation of the component E is the emulsion of the Tetrafluorethylenpolyme- risats (Teflon ^® 30N from DuPont) with the emulsion of the SAN Pfropfpolymeri- sats B mixed with 1.8 wt .-%, based on polymer solids, of phenolic antioxidants. At 85 to 95 ° C the mixture is coagulated with an aqueous solution of MgSO ₄ (Epsom salt) and acetic acid at pH 4 to 5, filtered and washed until practically free of electrolytes, then by centrifugation. Gation freed from the main amount of water and then dried at 100 ° C to a powder. This powder can then be compounded with the other components in the units described.

Production and testing of the compositions according to the invention

The components are mixed with the usual processing aids on a 3 1 internal kneader. The moldings are produced on an Arburg 270E injection molding machine at 260 ° C.

The heat resistance according to Vicat B is determined in accordance with DIN 53 460 on rods measuring 80 x 10 x 4 mm.

The notched impact strength a _j ^ is determined in accordance with ISO 180/1 A.

The flame resistance is determined according to UL 94 V.

To determine the tendency to yellowing, specimens measuring 60 x 40 x 2 mm (manufactured at 260 ° C) are stored in a forced-air oven at 100 ° C for 24 hours and then visually inspected.

Table: Compositions and their properties

l (see) 2

Components [% by weight]

A 65.7 65.7

B 7.5 7.5

C 7.5 7.5

Dl (TPP 0.1%) - 13.0

D2 (TPP 9.0%) 13.0 -

E 5.0 5.0

Mold release agent (PETS) * 0.4 0.4

l (V l) 2

characteristics

Vicat B 120 [° C] 99 102

UL 94 V 1.6 mm V-l V-0

Total afterburn time [sec] 60 35

Yellowing tendency - + when stored under heat

+ = no changes after heat storage - = significant yellowing after heat storage * PETS = pentaerythritol tetrastearate

From the table it can be seen that the composition 2 according to the invention with an IPP content of 0.1% by weight has a significantly improved notched impact strength (a _k ), improved heat resistance (Vicat B), a shorter afterburning time (UL-94) and a lower tendency to yellowing when stored under heat than that

Composition of Comparative Example 1 with an IPP content of 9 wt .-%.

Claims

claims

1. Polycarbonate composition containing a phosphorus compound of the general formula (I)

worm

Rl, R ^, R3 and R ⁴ , independently of one another, optionally substituted by halogen C 1 -C 6 -alkyl, each optionally substituted by halogen and / or alkyl C 5 to Cg-cycloalkyl, Cg to Cjo-aryl or C7 to Ci2-aralkyl,

n independently of one another 0 or 1,

independently of one another 0, 1, 2, 3 or 4,

N 0.1 to 5,

5 and R6 independently of one another are C 1 -C 4 -alkyl or halogen and

Isopropylidene mean

wherein the composition has an isopropenylphenyl phosphate content of less than 1% by weight, based on the mass of the phosphorus compound used.

2. Composition according spoke 1, wherein the isopropylphenyiphosphate content is less than 0.5 wt .-%, based on the mass of the phosphorus compound used.

3. Composition according spoke 1, wherein the isopropylphenyl phosphate content is less than 0.2 wt .-%, based on the mass of the phosphorus compound used.

4. Composition according to one of the preceding claims, containing 0.5 to 20 wt .-% of a phosphorus compound (I) or a mixture of phosphorus compounds (I).

5. Composition according to one of the preceding claims, which contains 0.5 to 60 wt .-% of a graft polymer.

6. Composition according to one of the preceding claims, containing

A) 40 to 99% by weight of an aromatic polycarbonate and / or polyester carbonate,

B) 0.5 to 60% by weight of a graft polymer,

C) 0 to 45% by weight of at least one thermoplastic polymer selected from the group of vinyl (co) polymers and polyalkylene terephthalates,

D) 0.5 to 20% by weight of a phosphorus compound of the general formula (I)

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , Y, N and n have the meaning given in claim 1,

E) 0 to 5% by weight fluorinated polyolefin.

7. Composition according spoke 1 to 6 containing as component B) one or more graft polymers of

B.l 5 to 95 wt .-% of at least one vinyl monomer

B.2 95 to 5% by weight of one or more graft bases with glass transition temperatures <10 ° C.

8. Composition according spoke 7, wherein the vinyl monomers B1 are selected from at least one monomer B1 of the group styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene and (Met fjacrylic acid-Cj-Cg-alkyl ester and at least one monomer B1.2 the group of vinyl cyanides, (Met ^ acrylic acid-Ci-Cg-alkyl esters and derivatives of unsaturated carboxylic acids and B.2 is selected from the group of diene rubbers, EP (D) M rubbers and acrylate rubbers.

Composition according spoke 7, wherein the vinyl monomers Bl are styrene and acrylonitrile and B.2 polybutadiene, which may contain up to 30 wt .-% (based on the rubber) comonomers selected from styrene, acrylonitrile, methyl methacrylate or mixtures thereof.

10. Compositions according to one of the preceding claims, containing at least one additive from the group consisting of stabilizers, pigments, mold release agents, flow aids and / or antistatic agents, fillers and reinforcing materials.

11. Moldings obtainable from a composition according to one of claims 1 to 10.

12. Use of phosphorus compounds of the general formula (I)

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , Y, N and n have the meaning given in spoke 1, with a content of isopropenylphenyl phosphate of less than 1 wt .-%, based on the mass the phosphorus compound used, as a flame retardant in polycarbonate and / or polyester carbonate compositions.

13. Use according to claim 12, wherein the phosphorus compound

Isopropylphenyl phosphate content of less than 0.5 wt .-%, based on the mass of the phosphorus compound used.

14. Use according to claim 12, wherein the phosphorus compound has an isopropylphenyl phosphate content of less than 0.2% by weight, based on the

Mass of the phosphorus compound used.