|Title of Invention||
"IMPACT-MODIFIED POLYMER COMPOSITION"
|Abstract||Polycarbonate compositions modified with graft polymer and containing phosphorus-containing compounds having the formula (Ia), wherein R1, R2, R3, R4, R5, R6, n, q, m and Y are as herein described as in specification and claims.|
|Full Text||Impact-modified polymer composition
The invention concerns an impact-modified polymer composition containing calcined talc and having improved mechanical properties and colour stability together with mouldings produced from the composition
It is known that talc can be added as a reinforcing material to increase the rigidity and tensile strength, to increase the dimensional stability under temperature fluctuations and to improve the surface properties of polycarbonate compositions. In flame-resistant matenals the talc addition also serves as a flame proofing synergist.
WO 00/148 074 describes flame-resistant and impact-modified polycarbonate compositions filled with talc. Calcined talc is not mentioned
JP-A 0 731 6411 describes PC/ABS moulding compositions that contain 1 to 30 % of an aromatic monophosphate as flame retardant and 1 to 20 % of a calcined talc having an average particle diameter of 2 µm or less as filler. The moulding compositions are characterised by good processabihty, toughness and heat resistance together with excellent flame proofing. Expenence teaches, however, that monophosphates have a tendency towards bleeding and the undesirable formation of plate-out when processed by injection moulding.
PC/SAN blends having polystyrene-grafted polybutadiene rubber as impact modifier and containing mineral fillers, e.g. talc, are known from WO 98/51737 Al. The use of calcined talc is not described The moulding compositions described are not flame resistant
US-A 5 162 419 describes PC/ABS moulding compositions containing talc having an average particle size of 1 5 to 20 µm, preferably 4.0 to 10 µm, to improve the surface appearance of injection moulded parts. The moulding compositions
described are charactensed by a matt surface and improved mechanical properties and are not flame resistant.
Flame-resistant PC/ABS compositions containing talc and phosphoric acid esters are known from JP-A 11/199768. The PC/ABS compositions described display an improved fire behaviour and are suitable in particular for thin-walled applications. Moulding compositions with calcined talc grades are not described.
EP-A 0 758 003 A2 describes PC moulding compositions that can contain inorganic fillers as reinforcing material. Talc inter alia is cited as filler. The PC moulding compositions can also be flame resistant and are charactensed by an improved surface appearance and a high modulus of elasticity Polycarbonate blends are not descnbed m this specification.
EP-A 0 391 413 describes PC/ABS moulding compositions containing inorganic fillers having special geometric properties, whereby the moulding compositions are distinguished by a low coefficient of linear and thermal expansion, high toughness under impact stress and high heat resistance. Non-calcined talc and clay materials are descnbed as fillers according to the invention Flame retardants are mentioned only generally m a list of additives.
The disadvantage of the talc-containing PC/ABS blends known from the pnor art is that important mechanical properties such as weld line strength and toughness are decisively reduced by the addition of talc. Particularly in the case of talc grades that are not highly pure, there is also a detenoration in the inherent colour of the matenal and in the ageing stability, particularly in the colour stability of the compositions under exposure to UV light.
It is therefore desirable to provide polycarbonate compositions to which talc is added by known means for the purpose of improving at least one matenal property, which
are characterised by an advantageous combination of weld line strength and colour stability and which display excellent flame resistance.
Surprisingly it was found that impact-modified polycarbonate moulding compositions containing a calcined talc and an oligomenc phosphoric acid ester as flame retardant display the desired range of properties.
The invention therefore provides polycarbonate moulding compositions modified with graft polymer and containing oligomenc phosphoric acid esters having the formula (I),
R1, R2, R3 and R4 each mutually independently denote optionally halogenated C1 to C8 alkyl, C5 to C6 cycloalkyl, C6 to C20 aryl or C7 to C12 aralkyl, each optionally substituted by alkyl, preferably C1 to C4 alkyl, and/or halogen, preferably chlorine, bromine,
n mutually independently denotes 0 or 1
q denotes 0.8 to 30 and
X denotes a mononuclear or polynuclear aromatic radical having 6 to 30 C atoms, or a linear or branched aliphatic radical having 2 to 30 C atoms, which can be OH-substituted and can contain up to 8 ether bonds,
and calcined talc.
Thermoplastic moulding compositions are preferred that contain
A) 40 to 99, preferably 50 to 90 parts by weight, particularly preferably 60 to 80 parts by weight of aromatic polycarbonate and/or polyester carbonate
B) 0.5 to 60, preferably 1 to 40, particularly 2 to 25 parts by weight of graft polymer of
B 1) 5 to 95, preferably 30 to 90 wt.% of one or more vinyl monomers on
B.2) 95 to 5, preferably 70 to 10 wt.% of one or more graft bases having a glass transition temperature C) 0 to 45, preferably 0 to 30, particularly preferably 2 to 25 parts by weight of at least one thermoplastic polymer, selected from the group of vinyl (co)polymers and polyalkylene terephthalates.
D) 0.5 to 20 parts by weight, preferably 1 to 18 parts by weight, particularly preferably 2 to 16 parts by weight of ohgomenc phosphoric acid esters having the aforementioned formula (I)
E) 0 2 to 20 parts by weight, preferably 0.5 to 15, particularly 0 8 to 12 parts by
weight of calcined talc and
F) 0 to 5, preferably 0.1 to 1, particularly 0.1 to 0.5 parts by weight of an anti-
dnpping agent, preferably a fluonnated polyolefin,
whereby the sum of all parts by weight equals 100. Component A
Aromatic polycarbonates and/or aromatic polyester carbonates according to component A that are suitable according to the invention are known from the literature or can be prepared by methods known from the literature (for the preparation of aromatic polycarbonates see for example Schnell, "Chemistry and Physics of Polycarbonates", Interscience Publishers, 1964, and DE-AS 1 495 626, DE-OS 2 232 877, DE-OS 2 703 376, DE-OS 2 714 544, DE-OS 3 000 610, DE-OS 3 832 396; for the preparation of aromatic polyester carbonates e g. DE-OS 3 077 934).
Aromatic polycarbonates are prepared for example by reacting diphenols with carbonic acid hahdes, preferably phosgene, and/or with aromatic dicarboxyhc acid dihahdes, preferably benzenedicarboxyhc acid dihahdes, by the interfacial polycondensation process, optionally using chain terminators, for example monophenols, and optionally using tnfunctional or polyfunctional branching agents, for example tnphenols or tetraphenols, or alternatively by the melt process
Diphenols for the preparation of the aromatic polycarbonates and/or aromatic polyester carbonates are preferably those having the formula (II),
A is a single bond, C1-C5 alkylene, C2-C5 alkylidene, C5-C6 cycloalkylidene, -O-, -SO-, -CO-, -S-, -SO2-, C6-C12 arylene, to which other aromatic rings optionally containing heteroatoms can be condensed,
or a radical having the formula (III) or (IV)
B is C1-C12 alkyl, preferably methyl, halogen, preferably chlorine and/or
x is mutually independently 0, 1 or 2,
p is 1 or 0, and
R7 and R8 can be individually selected for each X1 and mutually independently denote hydrogen or C1-C6 alkyl, preferably hydrogen, methyl or ethyl,
X1 denotes carbon and
m denotes a whole number from 4 to 7, preferably 4 or 5, with the proviso that in at least one X1 atom R7 and R8 are both alkyl.
Preferred diphenols are hydroqumone, resorcmol, dihydroxydiphenols,
bis(hydroxphenyl) ethers, bis(hydroxyphenyl) sulfoxides, bis(hydroxyphenyl) ketones, bis(hydroxyphenyl) sulfones and a,a-bis(hydroxyphenyl) dnsopropyl benzenes along with their nng-brominated and/or nng-chlonnated derivatives.
Particularly preferred diphenols are 4,4'-dihydroxydiphenyl, bisphenol A, 2,4-bis-(4-hydroxyphenyl)-2-rnethyl butane, l,l-bis-(4-hydroxyphenyl) cyclohexane, 1,1-bis-(4-hydroxyphenyl-3.3.5-trimethyl cyclohexane, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone and dibrominated and tetrabrominated or chlorinated denvatives thereof such as e g. 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 especially preferred.
The diphenols can be used individually or in any mixture whatsoever
The diphenols are known from the literature or can be obtained by methods known from the literature.
Suitable chain terminators for the preparation of the thermoplastic, aromatic polycarbonates are for example phenol, p-chlorophenol, p-tert -butyl phenol or 2,4,6-tnbromophenol, as well as long-chain alkyl phenols such as 4-(l,3-tetramethyl butyl) phenol according to DE-OS 2 842 005 or monoalkyl phenol or dialkyl phenols having a total of 8 to 20 C atoms in the alkyl substituents, such as 3,5-di-tert -butyl phenol, p-iso-octyl phenol, p-tert-octyl phenol, p-dodecyl phenol and 2-(3,5-dimethyl heptyl) phenol and 4-(3,5-dimethyl heptyl) phenol. The amount of chain
termmators to be used is generally between 0.5 mol% and 10 mol%, relative to the molar sum of diphenols used in each case.
The thermoplastic, aromatic polycarbonates have average weight-average molecular weights (Mw, measured e g. by ultracentnfuge or light-scattering measurement) of 10,000 to 200,000, preferably 20,000 to 80,000.
The thermoplastic, aromatic polycarbonates can be branched by known means, and preferably by the incorporation of 0.05 to 2.0 mol%, relative to the sum of diphenols used, of afunctional or polyfunctional compounds, for example those having three and more phenolic groups.
Both homopolycarbonates and copolycarbonates are suitable. 1 to 25 wt.%, preferably 2.5 to 25 wt.% (relative to the total amount of diphenols to be used) of polydiorganosiloxanes having hydroxyaryloxy terminal groups can also be used in the production of copolycarbonates according to the invention as component A. These are known (see for example US patent 3 419 634) or can be produced by methods known from the literature. The production of polydiorganosiloxane-contammg copolycarbonates is described e.g. in DE-OS 3 334 782.
In addition to the bisphenol A homopolycarbonates, preferred polycarbonates are the copolycarbonates of bisphenol A having up to 15 mol%, relative to the molar sums of diphenols, of other diphenols cited as being preferred or particularly preferred, in particular 2,2-bis-(3,5-dibromo-4-hydroxyphenyl) propane
Aromatic dicarboxyhc acid dihahdes for the production of aromatic polyester carbonates are preferably the di-acid dichlondes of isophthahc acid, terephthahc acid, diphenyl ether-4,4'-dicarboxyhc acid and naphthalme-2,6-dicarboxyhc acid
Mixtures of the di-acid dichlondes of isophthalic acid and terephthahc 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 also incorporated as a bifunctional acid derivative
Examples of chain terminators for the production of aromatic polyester carbonates also include, in addition to the monophenols already cited, chloroformic acid esters thereof and the acid chlorides of aromatic monocarboxyhc acids, which can optionally be substituted by C1-C22 alkyl groups or by halogen atoms, along with aliphatic C2-C22 monocarboxyhc acid chlondes.
The quantity of chain terminators in each case is 0.1 to 10 mol%, relative to moles of diphenols in the case of phenolic chain terminators and to moles of dicarboxylic acid dichlondes in the case of monocarboxyhc acid chloride chain terminators.
The aromatic polyester carbonates can also contain incorporated aromatic hydroxycarboxyhc acids.
The aromatic polyester carbonates can be both linear and branched by known means (see also DE-OS 2 940 024 and DE-OS 3 007 934 in this connection).
Examples of branching agents that can be used include tnfunctional or
polyfunctional carboxyhc acid chlondes, such as trimesic acid trichloride, cyanuric
acid trichloride, 3,3'-4,4'-benzophenone tetracarboxyhc acid tetrachloride, 1,4,5,8-
naphthaline tetracarboxyhc acid tetrachloride or pyromelhtic acid tetrachloride, in
quantities of 0 01 to 1.0 mol% (relative to dicarboxylic acid dichlondes used) or
tnfunctional or polyfunctional phenols, such as phloroglucinol, 4,6-dimethyl-2,4,6-
tn-(4-hydroxyphenyl) heptene-2,4,4-dimethyl-2,4,6-tn-(4-hydroxyphenyl) heptane,
l,3,5-tn-(4-hydroxyphenyl) benzene, l,l,l-tn-(4-hydroxyphenyl) ethane, tn-(4-
hydroxyphenyl) phenyl methane, 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-methylbenzyl)-4-methyl phenol, 2-(4-
hydroxyphenyl)-2-(2,4-dihydroxyphenyl) propane, tetra-(4-[4-hydroxyphenyl isopropyl] phenoxy) methane, l,4-bis-[4,4'-dihydroxytriphenyl) methyl] benzene, in quantities of 0 01 to 1.0 mol%, relative to diphenols used. Phenolic branching agents can be included with the diphenols, acid chloride branching agents can be introduced together with the acid dichlondes.
The proportion of carbonate structural units in the thermoplastic, aromatic polyester carbonates can vary widely The proportion of carbonate groups is preferably up to 100 mol%, m particular up to 80 mol%, particularly preferably up to 50 mol%, relative to the sum of ester groups and carbonate groups Both the ester and the carbonate component of the aromatic polyester carbonates can be in the form of blocks or randomly distributed in the polycondensate.
The relative solution viscosity (r)rei) of the aromatic polycarbonates and polyester carbonates is in the range from 1.18 to 1.4, preferably 1.22 to 1.3 (measured in solutions of 0.5 g polycarbonate or polyester carbonate in 100 ml methylene chloride solution at 25°C).
The thermoplastic, aromatic polycarbonates and polyester carbonates can be used alone or m any mixture with one another.
Component B comprises one or more graft polymers of
B. 1 5 to 95, preferably 30 to 90 wt %, of at least one vinyl monomer on
B.2 95 to 5, preferably 70 to 10 wt.%, or one or more graft bases having glass transition temperatures The graft base B.2 generally has an average particle size (d50 value) of 0.05 to 5 µm, preferably 0.10 to 2 µm, particularly preferably 0.20 to 1 µm, in particular 0.2 to 0.5 µm
Monomers B.l are preferably mixtures of
B.l.l 50 to 99 parts by weight of vinyl aromatics and/or ring-substituted vinyl aromatics (such as e.g styrene, a-methyl styrene, p-methyl styrene, p-chlorostyrene) and/or (meth)acrylic acid (C1-C8) alkyl esters (such as e.g. methyl methacrylate, ethyl methacrylate) and
B.1.2 1 to 50 parts by weight of vinyl cyanides (unsaturated nitnles such as acrylonitrile and methacrylonitnle) and/or (meth)acryhc acid (C1-C8) alkyl esters (such as e.g. methyl methacrylate, n-butyl acrylate, t-butyl acrylate) and/or derivatives (such as anhydrides and imides) of unsaturated carboxyhc acids (for example maleic anhydride and N-phenyl maleimmide).
Preferred monomers B.l.l are selected from at least one of the monomers styrene, Dimethyl styrene and methyl methacrylate, preferred monomers B 1.2 are selected from at least one of the monomers acrylonitrile, maleic anhydride and methyl methacrylate.
Particularly preferred monomers are B.l.l styrene and B.1.2 acrylonitrile.
Suitable graft bases B.2 for the graft polymers B are for example diene rubbers, EP(D)M rubbers, I e those based on ethylene/propylene and optionally diene, acrylate, polyurethane, silicone, chloroprene and ethylene/vmyl 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 mixtures thereof with
other copolymensable monomers (e.g. according to B.l 1 and B.l 2), preferably butadiene-styrene copolymers, with the proviso that the glass transition temperature of component B.2 is below Pure polybutadiene rubber is particularly preferred.
Particularly preferred polymers B are e.g. ABS polymers (emulsion, bulk and suspension ABS), such as are described e.g in DE-OS 2 035 390 (=US-PS 3 644 574) or in DE-OS 2 248 242 (=GB-PS 1 409 275) or in Ullmann, Enzyklopadie der Techmschen Chemie, Vol. 19 (1980), p 280 ff. The gel component of graft base B.2 is at least 30 wt.%, preferably at least 40 wt.% (measured in toluene).
The graft copolymers B are produced by radical polymerisation, e.g by emulsion, suspension, solution or bulk polymerisation, preferably by emulsion polymerisation or bulk polymerisation.
Particularly suitable graft rubbers are also ABS polymers produced by redox initiation with an initiator system of organic hydroperoxide and ascorbic acid according to US-P 4 937 285.
Since it is known that the graft monomers are not necessarily completely grafted onto the graft base during the graft reaction, graft polymers B according to the invention also refer to such products that are obtained by (co)polymensation of the graft monomers in the presence of the graft base and that co-accumulate during preparation.
Suitable acrylate rubbers according to B 2 for the polymers B are preferably polymers of acrylic acid alkyl esters, optionally with up to 40 wt.%, relative to B 2, of other polymensable, ethylenically unsaturated monomers The preferred polymensable acrylic acid esters include C1-C8 alkyl esters, for example methyl,
ethyl, butyl, n-octyl and 2-ethylhexyl ester; haloalkyl esters, preferably halogen Cr C8 alkyl esters, such as chloroethyl acrylate, and mixtures of these monomers.
Monomers having more than one polymerisable double bond can be copolymensed for crosshnkmg. Preferred examples of crosslinkmg monomers are esters of unsaturated monocarboxylic acids with 3 to 8 C atoms and unsaturated monohydnc alcohols with 3 to 12 C atoms, or saturated polyols with 2 to 4 OH groups and 2 to 20 C atoms, such as eg. ethylene glycol dimethacrylate, allyl methacrylate; polyunsaturated heterocyclic compounds, such as e g. trivinyl and tnallyl cyanurate; polyfunctional vinyl compounds, such as divmyl and tnvmyl benzenes; but also tnallyl phosphate and diallyl phthalate.
Preferred crosshnkmg monomers are allyl methacrylate, ethylene glycol dimethacrylate, diallyl phthalate and heterocyclic compounds displaying at least 3 ethylenically unsaturated groups
Particularly preferred crosslinkmg monomers are the cyclic monomers tnallyl cyanurate, tnallyl isocyanurate, tnacryloyl hexahydro-s-tnazme, tnallyl benzenes. The quantity of crosshnking monomers is preferably 0 02 to 5, particularly 0 05 to 2 wt %, relative to the graft base B.2
In the case of cyclic crosshnkmg monomers with at least 3 ethylenically unsaturated groups it is advantageous to restrict the quantity to below 1 wt.% of the graft base B2.
Preferred "other" polymerisable, ethylenically unsaturated monomers which can optionally serve to produce the graft base B.2 m addition to the acrylic acid esters are eg acrylonitnle, styrene, α-methyl styrene, acrylamides, vmyl C1-C6 alkyl ethers, methyl methacrylate, butadiene. Preferred acrylate rubbers as graft base B 2 are emulsion polymers displaying a gel content of at least 60 wt.%.
Other suitable graft bases according to B.2 are silicone rubbers with graft-active sites, such as are described in DE-OS 3 704 657, DE-OS 3 704 655, DE-OS 3 631 540 and DE-OS 3 631 539.
The gel content of graft base B 2 is determined at 25°C in a suitable solvent (M. Hoffmann, H. Kromer, R. Kuhn, Polymeranalytik I and II, Georg Thieme-Verlag, Stuttgart 1977).
The average particle size d50 is the diameter above and below which respectively 50 wt.% of the particles lie. It can be determined by ultracentnfuge measurement (W. Scholtan, H. Lange, Kolloid, Z. und Z. Polymere 250 (1972), 782-1796).
Component C includes one or more thermoplastic vinyl (co)polymers C.l and/or polyalkylene terephthalates C.2.
Suitable vmyl (co)polymers C.l are polymers of at least one monomer from the group of vmyl aromatics, vmyl cyanides (unsaturated mtriles), (meth)acryhc acid C1-C8 alkyl esters, unsaturated carboxyhc acids and derivatives (such as anhydrides and lmides) of unsaturated carboxyhc acids Particularly suitable are (co)polymers consisting of
C.l 1 50 to 99, preferably 60 to 80 parts by weight of vmyl aromatics and/or ring-substituted vmyl aromatics, such as e.g. styrene, a-methyl styrene, p-methyl styrene, p-chlorostyrene), and/or (meth)acrylic acid (C1-C8) alkyl esters, such as e.g methyl methacrylate, ethyl methacrylate), and
C.l.2 1 to 50, preferably 20 to 40, parts by weight of vmyl cyanides (unsaturated nitnles), such as acrylonitnle and methacrylonitnle and/or (meth)acryhc acid (C1-C8) alkyl esters (such as e.g methyl methacrylate, n-butyl acrylate, t-
butyl acrylate) and/or unsaturated carboxylic acids (such as maleic acid) and/or derivatives (such as anhydrides and lmides) of unsaturated carboxylic acids (for example maleic anhydride and N-phenyl maleinimide).
The (co)polymers C.l are resinous, thermoplastic and rubber-free.
The copolymer of C.l. 1 styrene and C.l.2 acrylomtnle is particularly preferred
The (co)polymers according to C 1 are known and can be produced by radical polymerisation, in particular by emulsion, suspension, solution or bulk polymerisation. The (co)polymers preferably have molecular weights Mw (weight average, determined by light scattering or sedimentation) of between 15,000 and 200,000.
The polyalkylene terephthalates in component C.2 are reaction products of aromatic dicarboxylic acids or reactive derivatives thereof, such as dimethyl esters or anhydrides, and aliphatic, cycloahphatic or araliphatic diols and mixtures of these reaction products.
Preferred polyalkylene terephthalates contain at least 80 wt %, preferably at least 90 wt.%, relative to the dicarboxylic acid component, of terephthalic acid radicals and at least 80 wt.%, preferably at least 90 mol%, relative to the diol component, of ethylene glycol and/or butanediol-1,4 radicals.
In addition to terephthalic acid radicals, the preferred polyalkylene terephthalates can contain up to 20 mol%, preferably up to 10 mol%, of radicals of other aromatic or cycloahphatic dicarboxylic acids with 8 to 14 C atoms or aliphatic dicarboxylic acids with 4 to 12 C atoms, such as e.g. radicals of phthahc acid, isophthahc acid, naphthahne-2,6-dicarboxyhc acid, 4,4'-diphenyl dicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, cyclohexane diacetic acid
In addition to ethylene glycol or butanediol-1,4 radicals, the preferred polyalkylene terephthalates can contain up to 20 mol%, preferably up to 10 mol%, of other aliphatic diols with 3 to 12 C atoms or cycloaliphatic diols with 6 to 21 C atoms, e.g. radicals of propanediol-1,3, 2-ethyl propanediol-1,3, neopentyl glycol, pentanediol-1,5, hexanediol-1,6, cyclohexane dimethanol-1,4, 3-ethyl pentanediol-2,4, 2-methyl pentanediol-2,4, 2,2,4-tnmethyl pentanediol-1,3, 2-ethyl hexanediol-1,3, 2,2-diethyl propanediol-1,3, hexanediol-2,5, l,4-di-(|3-hydroxyethoxy)benzene, 2,2-bis-(4-hydroxycyclohexyl) propane, 2,4-dihydroxy-l,l,3,3-tetramethyl cyclobutane, 2,2-bis-(4-P-hydroxyethoxyphenyl) propane and 2,2-bis-(4-hydroxypropoxyphenyl) propane (DE-OS 2 407 674, 2 407 776, 2 715 932).
The polyalkylene terephthalates can be branched by incorporating relatively small amounts of trihydnc or tetrahydric alcohols or tnbasic or tetrabasic carboxylic acids, e.g. according to DE-OS 1 900 270 and US-PS 3 692 744 Examples of preferred branching agents are tnmesic acid, trimelhtic acid, tnmethylol ethane and propane and pentaerythntol
Polyalkylene terephthalates produced solely from terephthalic acid and reactive denvatives thereof (e.g. dialkyl esters thereof) and ethylene glycol and/or butanediol-1,4, and mixtures of these polyalkylene terephthalates, are particularly preferred
Mixtures of polyalkylene terephthalates contain 1 to 50 wt.%, preferably 1 to 30 wt %, of polyethylene terephthalate and 50 to 99 wt.%, preferably 70 to 99 wt %, of polybutylene terephthalate.
The polyalkylene terephthalates that are 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 an Ubbelohde viscometer.
The polyalkylene terephthalates can be produced by known methods (see eg. Kunststoff-Handbuch, Volume VIE, page 695 ff., Carl-Hanser-Verlag, Munich 1973).
The compositions according to the invention contain as flame retardants oligomenc phosphonc acid esters having the general formula (I),
in which the radicals have the meanings cited above.
R1, R2, R3 and R4 preferably mutually independently stand for C1 to C4 alkyl, phenyl, naphthyl or phenyl C1-C4 alkyl. The aromatic groups R1, R2, R3 and R4 can be substituted for their part with halogen and/or alkyl groups, preferably chlorine, bromine and/or C1 to C4 alkyl. Particularly preferred aryl radicals are cresyl, phenyl, xylenyl, propyl phenyl or butyl phenyl and the corresponding brommated and chlorinated derivatives thereof
X in formula (I) preferably denotes a mononuclear or polynuclear aromatic radical with 6 to 30 C atoms This preferably derives from diphenols having formula (II)
n in formula (I) can mutually independently be 0 or 1, whereby n preferably
q stands for values from 0.8 to 30. If mixtures of different components of
formula (I) are used, mixtures preferably having number-averaged q values of 0.8 to 20, particularly preferably 0.9 to 10, in particular 1 to 3, can be used.
X particularly preferably stands for
or chlorinated or brominated derivatives thereof, in particular X derives from resorcmol, hydroqumone, bisphenol A or diphenyl phenol. X particularly preferably derives from bisphenol A.
The use of ohgomenc phosphonc acid esters having formula (I) derived from bisphenol A (cf formula (la)) is particularly advantageous, since compositions contaimng this phosphorus compound display a particularly high stress cracking resistance and hydrolysis resistance and a particularly low tendency towards plate-out when processed by injection moulding. Furthermore, a particularly high heat resistance can be achieved with these flame retardants.
Particularly preferred phosphorus-containing compounds are compounds having the formula (la),
R1 R2, R3, R4, n and q have the meaning cited for formula (I),
m mutually independently denotes 0, 1, 2, 3 or 4,
R5 and R6 mutually inpendently denote C1to C4 alkyl, preferably methyl or ethyl and
Y denotes C1 to C7 alkylidene, C1-C7 alkylene, C5 to C12 cycloalkylene, C5 to C12 cycloalkylidene, -O-, -S-, -SO2 or -CO-, preferably isopropylidene or methylene.
The phosphorus compounds according to component E are known (cf e.g. EP-A 0 363 608, EP-A 0 640 655) or can be produced by known methods m an analogous way (e.g. Ullmanns Enzyklopadie der technischen Chemie, Vol. 18, p. 301 ff. 1979, Houben-Weyl, Methoden der orgamschen Chemie, Vol. 12/1, p 43, Beilstein, Vol. 6, p. 177)
The average q values can be determined by determining the composition of the phosphate mixture (molecular weight distribution) by a suitable method (gas chromatography (GC), high-pressure liquid chromatography (HPLC), gel permeation chromatography (GPC)) and using it to calculate the average values for q
The compositions according to the invention contain calcined talc. This can be obtained by the calcination of talc, i.e. thermal treatment at high temperatures, preferably at temperatures > 1000°C, by known means. The calcined talc can be surface treated, e.g. silanised, to improve the contact with the polymer Calcined talc is commercially available, e.g. from Nippon Talc K.K., Japan, or Hayashe Kasei K.K., Japan.
Calcination refers to the fact that in general, at temperatures above 900°C talc gradually loses its hydroxyl groups and at temperatures above 1050°C recrystalhses to the form of enstatite, an anhydrous magnesium silicate having the formula Mg2[Si206]. The calcined talc according to component E) therefore contains at least one chosen from enstatite and dehydroxylated talc.
The flame retardants according to component D are often used in combination with anti-dripping agents, which reduce the tendency of the material to form burning drips m the event of a fire Compounds from the substance classes of fluonnated polyolefins, silicones and aramid fibres can be cited here by way of example. These can also be used in the compositions according to the invention. Fluonnated polyolefins are preferably used as anti-dnppmg agents.
Fluonnated polyolefins are known and descnbed for example m EP-A 0 640 655. They are sold by DuPont, for example, under the brand name Teflon® 3 ON.
The fluonnated polyolefins can be used both in pure form and in the form of a coagulated mixture of emulsions of the fluonnated polyolefins with emulsions of the graft polymers (component B) or with an emulsion of a copolymer, preferably on a
styrene/acrylonitnle basis, whereby the fluorinated polyolefin is mixed as an emulsion with an emulsion of the graft polymer or copolymer and then coagulated.
The fluorinated polyolefins can further be used as a pre-compound with the graft polymer (component B) or a copolymer, preferably on a styrene/acrylonitnle basis. The fluorinated polyolefins are mixed as a powder with a powder or pellets of the graft polymer or copolymer and compounded in the melt, generally at temperatures of 200 to 330°C, in conventional units such as internal mixers, extruders or twin screws.
The fluorinated polyolefins can also be used in the form of a masterbatch, which is produced by emulsion polymerisation of at least one monoethylemcally unsaturated monomer in the presence of an aqueous dispersion of the fluorinated polyolefin. Preferred monomer components are styrene, acrylomtnle and mixtures thereof The polymer is used as a free-flowing powder after acid precipitation and subsequent drying.
The coagulates, pre-compounds or masterbatches conventionally have solids contents of 5 to 95 wt.%, preferably 7 to 60 wt.%, of fluorinated polyolefin.
The stated quantities of fluorinated polyolefins relate to the absolute quantity of fluorinated polyolefin.
Component G (other additives)
The compositions according to the invention can also contain at least one of the conventional additives, such as lubncants and release agents, for example pentaerythntol tetrastearate, nucleating agents, antistatics, stabilisers, and other fillers and reinforcing agents along with dyes and pigments.
The compositions according to the invention can contain up to 35 wt.%, relative to the overall composition, of an additional, optionally synergistically acting flame retardant Examples of additional flame retardants that can be cited are silicones, organic halogen compounds such as decabromobisphenyl ether, tetrabromobisphenol, inorganic halogen compounds such as ammonium bromide, nitrogen compounds, such as melamine, melamme-formaldehyde resins, inorganic hydroxide compounds such as Mg, Al hydroxide, inorganic compounds such as antimony oxides, barium metaborate, hydroxoantimonate, 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.
The sum of the percentages by weight of all components equals 100.
The compositions according to the invention are produced by mixing the various constituents by known means and melt compounding and melt extruding them at temperatures of 200°C to 300°C in conventional umts such as internal mixers, extruders and twin screws.
The individual constituents can be mixed by known means both successively and simultaneously, both at around 20°C (room temperature) and at elevated temperature.
The compositions according to the invention can be used in the production of all types of mouldings. These can be produced for example by injection moulding, extrusion and blow moulding processes. A further form of processing is the production of mouldings by thermoforming from prefabncated sheets or films
Examples of such mouldings are films, profiles, all types of housing sections, e g for domestic appliances such as juice extractors, coffee machines, mixers; for office equipment such as monitors, printers, copiers, also plates, pipes, electric wiring
ducts, profiles for the construction sector, interior fittings and exterior applications, parts for the electrical engineering sector such as switches and plugs and interior and exterior automotive parts.
The compositions according to the invention can in particular be used to produce the following mouldings or moulded parts, for example:
Interior fittings for rail vehicles, ships, aircraft, buses and cars, hub caps, housings for electrical appliances containing miniature transformers, housings for equipment for information dissemination and transfer, housings and cladding for medical purposes, massage equipment and housings, toy vehicles for children, two-dimensional prefabricated wall panels, housings for safety equipment, rear spoilers, automotive body parts, heat-insulated transport containers, equipment for handling or caring for small animals, moulded parts for sanitary and bathroom equipment, covering grid plates for ventilator openings, moulded parts for garden sheds and tool sheds, housings for gardening implements.
The following examples are intended to illustrate the invention in more detail.
The components set out in Table 1 and briefly described below are compounded on a ZSK-25 at 240°C. The mouldings are produced on an Arburg 270 E injection moulding machine at 240°C.
Linear polycarbonate based on bisphenol A with a relative solution viscosity of 1.24, measured in CH2CI2 as solvent at 25°C and in a concentration of 0.5 g/100 ml.
Graft polymer of 40 parts by weight of a copolymer of styrene and acrylonitrile in the ratio 73.27 on 60 parts by weight of particulate crosslmked polybutadiene rubber (average particle diameter d50 = 0.3 µm), produced by emulsion polymerisation.
Styrene/acrylonitnle copolymer with a ratio of styrene to acrylonitrile of 72 28 and an intrinsic viscosity of 0.55 dl/g (measurement in dimethyl formamide at 20°C).
Phosphate based on bisphenol A
In order to determine the average q value, the contents of oligomeric phosphates
were first determined by HPLC measurements:
Column type- LiChrosorp RP-8
Eluent in gradient: acetonitrile/water 50.50 to 100:0
Concentration: 5 mg/ml
The number-weighted average values were then calculated from the contents of the individual components (monophosphates and ohgophosphates) by known methods.
Chlorite talc with a chlorite content of 20 wt.% and an average particle diameter dso = 2.0 urn
Calcined talc (produced from El by calcination at 1000°C).
Tetrafluoroethylene polymer as a coagulated mixture of a graft polymer emulsion according to the aforementioned component B m water and a tetrafluoroethylene
polymer emulsion in water. The ratio by weight of graft polymer B to the tetrafluoroethylene polymer in the mixture is 90 wt.% to 10 wt.% The tetrafluoroethylene polymer emulsion has a solids content of 60 wt %; the average particle diameter is between 0.05 and 0.5 µm. The graft polymer emulsion has a solids content of 34 wt.%.
The emulsion of the tetrafluoroethylene polymer (Teflon® 30 N from DuPont) is mixed with the emulsion of the graft polymer B and stabilised with 1 8 wt.%, relative to polymer solids, of phenolic antioxidants. The mixture is coagulated with an aqueous solution of MgSO4 (Epsom salts) and acetic acid at pH 4 to 5 and at a temperature of 85 to 95°C, filtered and washed until it is practically free from electrolytes, then freed from the bulk of the water by centnfugmg and subsequently dried to a powder at 100°C
Pentaerythntol tetrastearate (PETS) as release agent
Testing the properties of the moulding compositions according to the invention
The impact strength an is determined inccordance with ISO 180/1 U
To determine the weld line strength, the impact strength is measured at the weld line of specimens gated on both sides and measuring 170 x 10x4 mm m accordance with ISO 179/1 eU
The fire behaviour of the flame resistant specimens was measured on test pieces measuring 127 x 12.7 x 0.8 mm in accordance with UL-Subj. 94 V.
The Vicat B heat resistance is determined in accordance with ISO 306 on test pieces measunng 80 x 10x4 mm.
The melt viscosity is determined m accordance with DIN 54 811 at a shear rate of 1000 s"1 and a temperature of 260°C.
The colour stability is determined in accordance with ASTM D 4459, whereby sheets of the material are exposed to a defined UV irradiation for a total of 300 h and the chromaticity changes delta E relative to the initial value are determined after exposure times of 150 h and 300 h by spectral photometry.
Table 1 Moulding compositions and their properties
The table shows that calcined talc can be used in combination with ohgomenc phosphonc acid esters as FR additive to obtain PC/ABS moulding compositions that are characterised by improved mechanical properties (toughness and weld line strength) and improved UV resistance with excellent flame resistance, flowabihty and heat resistance.
1. Polycarbonate compositions modified with graft polymer and containing phosphorus-
containing compounds having the formula (Ia),
R1, R2, R3 and R4 each mutually independently denote optionally halogenated C1 to C8 alkyl, C5 to C6 cycloalkyl, C6 to C20 aryl or C7 to C12 aralkyl each optionally substituted by alkyl,
n mutually independently denotes 1 or 1
q denotes 0.8 to 30 and
m mutually independently denotes 0,1,2, 3 or 4
R5 and R6 mutually independently denote C1 to C4 alkyl, preferably methyl or ethyl, and Y denotes C1 to C7 alkylidene, C1-C7 alkylene, -O-, -S-, -SO2 or -CCO-, and calcined talc.
2. Compositions as claimed in claim 1 containing
A) 50 to 90 parts by weight of aromatic polycarbonate and/or polyester carbonate
B) 1 to 40 parts by weight of graft polymer of
B.1) 5 to 95 wt.% of one or more vinyl monomers on
B.2) 95 to 5wt.% of one or more graft bases having a glass transition temperature
C) 0 to 45 parts by weight of at least one thermoplastic polymer, selected from the group of vinyl (co)polymers and polyalkylene terephthalates.
D) 0.5 to 20 parts by weight of oligomeric phosphoric acid esters of formula (Ia)
E) 0.2 to 20 parts by weight of calcined talc and
F) 0 to 5 parts by weight of an anti-dripping agent,
wherein the sum of all parts by weight equals 100.
3. Composition as claimed in claim 1, wherein in the formula (Ia) q stands for number-averaged values of 0.8 to 20.
4. Composition as claimed in claim 3, wherein in the formula (Ia) q stands for 0.9 to 10.
5. Composition as claimed in claim 4, wherein in the formula (Ia) q stands for 1 to 3.
6. Composition as claimed in one of claims 1 to 5, wherein Y in formula (Ia) denotes isopropylidene.
7. Composition as claimed in claim 1 containing 50 to 90 parts by weight of A), 1 to 40 parts by weight of B), 0 to 30 parts by weight of C), 1 to 18 parts by weight of D), 0.5 to 15 parts by weight of calcined talc and 0.1 to 1 parts by weight of F), wherein the sum of all parts by weight equals 100.
8. Composition as claimed in claim 2, wherein component B.1 is a mixture of
B.1.1 50 to 99 wt.% of at least one monomer selected from the group of vinyl aromatics, ring-substituted vinyl aromatics and (meth)acrylic acid (C1-C8) alkyl esters and
B.1.2 1 to 50 wt.% of at least one monomer selected from the group of vinyl cyanides, (meth)acrylic acid (C1-C8) alkyl esters and derivatives of unsaturated carboxylic acids.
9. Composition as claimed in claim 8, wherein monomers B.1.1 are selected from at least one of the monomers styrene, a-methyl styrene and methyl methacrylate and monomers B.1.2 are selected from at least one of the monomers acrylonitrile, maleic anhydride and methyl methacrylate.
10. Composition as claimed in claim 2, wherein the graft base B.2 is selected from at least one of the group consisting of diene rubbers, EP(D)M rubbers, acrylate, polyurethane, silicone, chloroprene and ethylene/vinyl acetate rubbers.
11. Composition as claimed in claim 10, wherein the graft base B.2 is selected from at least one of the group of diene rubbers, butadiene/styrene copolymers and acrylate rubbers.
12. Composition as claimed in claim 3, wherein vinyl (co)polymers are polymers of at least one monomer from the group of vinyl aromatics, vinyl cyanides, (meth)acrylic acid (C1-C8) alkyl esters and unsaturated carboxylic acids and derivatives of unsaturated carboxylic acids and derivatives of unsaturated carboxylic acids.
13. Composition as claimed in claim 2, wherein component E) is fluorinated polyolefins.
14. Composition as claimed in claim 1, containing at least one additive selected from the group of lubricants and release agents, nucleating agents antistatics, stabilizers, additional fillers and reinforcing agents, dyes and pigments.
15. Use of the compositions as claimed in claim 1 for the production of moulded parts.
16. Moulded parts obtainable from compositions as claimed in claim 1.
|Indian Patent Application Number||2848/DELNP/2004|
|PG Journal Number||07/2013|
|Date of Filing||23-Sep-2004|
|Name of Patentee||BAYER MATERIALSCIENCE AG|
|Applicant Address||D-51368 LEVERKUSEN, GERMANY|
|PCT International Classification Number||C08L 69/00|
|PCT International Application Number||PCT/EP2003/02683|
|PCT International Filing date||2003-03-14|