AU3035500A - Flameproof extrudates and flameproof moulded bodies produced by means of pressing methods - Google Patents

Description

WO 00/36013 PCT/EP99/09494 Flame-protected extrudates, and flame-protected moulded articles produced by means of compression moulding processes The invention relates to flame-protected extrudates, especially films, sheets and 5 wire-coatings, based on polyalkylene terephthalate and pentabromobenzyl polyacrylate (PBBPA) having improved resistance to tearing and elongation at tear (stress at break and breaking elongation), electrical properties and surface quality. As is known, for example, from the literature Kunststoffe 80 (1990), pages 3 and 4, 10 plastics, such as thermosetting plastics, elastomers, polyamide, polycarbonate, etc., can be rendered flame-resistant by the use of halogenated hydrocarbons. It will be seen from the literature references mentioned above that although plastics parts containing halogenated hydrocarbons have a good flame-resisting action, they 15 have a poor surface quality on account of the halogen-containing flame-protecting additives used hitherto, so that it is not possible to produce flame-protected films or mouldings having very thin walls from PBT. Pentabromobenzyl mono- and poly-acrylate and their use as a flame-protecting agent 20 in thermoplastic resins are described in EP-A 344 700. Extrudates, such as, for example, films and sheets, having the desired properties are not described therein. The object of the present invention is to provide flame-protected extrudates, such as films, sheets and wire-coatings, based on polyalkylene terephthalate and a 25 commercially available, inexpensive and hence economical flame-protecting agent, which extrudates have a high surface quality, improved electrical properties and improved resistance to tearing and elongation at tear (stress at break and breaking elongation) and can be produced from the thermoplastic moulding compositions in a simple manner by conventional techniques, for example extrusion, blow moulding, 30 compression moulding processes.

WO 00/36013 PCT/EP99/09494 -2 It has been found that extrudates (films, sheets and wire-coatings) and moulded articles produced by the compression moulding process which are based on polyalkylene terephthalate and which are provided with a pentabromobenzyl polyacrylate (PBBPA) unexpectedly have an excellent surface and good flow 5 properties while at the same time having very good flame-resistant behaviour with a high resistance to tearing and elongation at tear (stress at break and breaking elongation), their electrical properties being high and the remaining properties being good, without the thermoplastic matrix being damaged. A further advantage of the invention is that the thermoplastic moulding compositions based on polyalkylene 10 terephthalate and PBBPA can be processed in an excellent manner to extrudates (films, sheets and wire-coatings), for example by extrusion, blow moulding, the drawing out of looms, and to moulded articles by compression moulding processes. The extrudates (films, sheets and wire-coatings) and moulded articles, produced by the compression moulding process, according to the invention can then be processed 15 further by conventional techniques, for example deep drawing, printed on and/or inscribed by laser. The present invention provides moulded articles produced by the compression moulding process and extrudates, especially films, sheets and wire-coatings, based 20 on thermoplastic moulding compositions containing A) from 55 to 97.7 parts by weight, preferably from 60 to 95.5 parts by weight, especially from 70 to 95 parts by weight, of polyalkylene terephthalate, 25 B) from 2 to 30 parts by weight, preferably from 3 to 25 parts by weight, especially from 4 to 20 parts by weight, of pentabromobenzyl polyacrylate, C) from 0.3 to 12 parts by weight, preferably from 0.5 to 10 parts by weight, especially from 1 to 8 parts by weight, of antimony compound(s), and 30 D) from 0 to 90 parts by weight of polycarbonate and/or polyester carbonate, WO 00/36013 PCT/EP99/09494 -3 wherein the sum of A) + B) + C) + D) is 100 and up to 10 parts by weight of polyalkylene terephthalate can be replaced by polyolefins. 5 The extrudates (films, sheets and wire-coatings) and moulded articles produced by the compression moulding process are obtainable from thermoplastic moulding compositions containing the above-mentioned components A) to D). The thermoplastic moulding compositions are distinguished by good flame-resistant behaviour, without the thermoplastic matrix being damaged, in conjunction with a 10 high surface quality and improved electrical properties and are especially suitable for the production of films and sheets owing to their good flow properties. The invention relates also to the use of thermoplastic moulding compositions containing the above-mentioned components in the production of flame-protected 15 extrudates (films, sheets and wire-coatings) and flame-protected moulded articles produced by the compression moulding process having improved properties in respect of breaking elongation, stress at break and surface quality. The term "films" usually refers to materials which can be rolled up, whereas sheets 20 are generally stiff and hence cannot be rolled up. Films within the scope of the invention generally have a thickness < 1200 pm, preferably from 25 to 1000 tm, especially from 50 to 850 pm. 25 Sheets within the scope of the invention generally have a thickness of from 1.2 mm to several centimetres, preferably from 1.2 mm to 4 cm, especially from 1.2 mm to 2.5 cm.

WO 00/36013 PCT/IEP99/09494 -4 Component A Polyalkylene terephthalates (component A) within the scope of the invention are reaction products of aromatic dicarboxylic acids or their reactive derivatives (e.g. 5 dimethyl esters or anhydrides) and aliphatic, cycloaliphatic or araliphatic diols, and mixtures of those reaction products. Preferred polyalkylene terephthalates can be prepared from terephthalic acid (or its reactive derivatives) and aliphatic or cycloaliphatic diols having from 2 to 10 carbon 10 atoms by known methods (Kunststoff-Handbuch, Vol. VIII, p. 695 ff, Karl-Hanser Verlag, Munich, 1973). Preferred polyalkylene terephthalates contain at least 80 mol%, preferably 90 mol%, based on the dicarboxylic acid, of terephthalic acid radicals and at least 80 mol%, 15 preferably at least 90 mol%, based on the diol component, of ethylene glycol and/or 1,4-butanediol radicals or a mixture thereof with 1,4-cyclohexanediol. The preferred polyalkylene terephthalates can contain, in addition to terephthalic acid radicals, up to 20 mol% of radicals of other aromatic dicarboxylic acids having 20 from 8 to 14 carbon atoms or of aliphatic dicarboxylic acids having from 4 to 12 carbon atoms, such as radicals of phthalic acid, isophthalic acid, naphthalene-2,6 dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, cyclohexanediacetic acid. 25 The preferred polyalkylene terephthalates can contain, in addition to ethylene glycol and/or 1,4-butanediol radicals, up to 20 mol% of other aliphatic diols having from 3 to 12 carbon atoms or of cycloaliphatic diols having from 6 to 21 carbon atoms, for example radicals of 1,3-propanediol, 2-ethyl-1,3-propanediol, neopentyl glycol, 1,5 pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 3 30 methyl-2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,2,4-trimethyl-1,3-pentanediol and -1,6,2-ethyl-1,3-hexanediol, 2,2-diethyl-1,3-propanediol, 2,5-hexanediol, 1,4-di- WO 00/36013 PCT/EP99/09494 -5 (p-hydroxyethoxy)-benzene, 2,2-bis(4-hydroxycyclohexyl)-propane, 2,4-dihydroxy 1,1,3,3-tetramethyl-cyclobutane, 2,2-bis(3-p-hydroxyethoxyphenyl)-propane and 2,2-bis(4-hydroxypropoxyphenyl)-propane (DE-OS 24 07 674, 24 07 776, 27 15 932). 5 The polyalkylene terephthalates can be branched by the incorporation of relatively small amounts of tri- or tetra-hydric alcohols or of tri- or tetra-basic carboxylic acids, as are described, for example, in DE-OS 19 00 270 and US-A 3 692 744. Examples of preferred branching agents are trimesic acid, trimellitic acid, 10 trimethylol-ethane and -propane and pentaerythritol. It is advisable to use not more than 1 mol% of the branching agent, based on the acid component. 15 Special preference is given to polyalkylene terephthalates that have been prepared solely from terephthalic acid and its reactive derivatives (e.g. its dialkyl esters), diols selected from ethylene glycol, 1,4-butanediol and 1,4-cyclohexanediol or mixtures thereof (polyethylene and polybutylene terephthalate), and mixtures of those polyalkylene terephthalates. 20 Preferred polyalkylene terephthalates are also copolyesters which are prepared from at least two of the above-mentioned acid components and/or from at least two of the above-mentioned alcohol components, and especially preferred copolyesters are poly-(ethylene glycol/ 1,4-butanediol) terephthalates. 25 The polyalkylene terephthalates preferably used as component A generally have an intrinsic viscosity of approximately from 0.4 to 1.5 dl/g, preferably from 0.5 to 1.3 dl/g, in each case measured in phenol/o-dichlorobenzene (1:1 parts by weight) at 25 0 C. 30 WO 00/36013 PCT/EP99/09494 -6 Component B Pentabromobenzyl polyacrylate is generally known and is described, for example, in EP-A 344 700. It is available commercially (Dead Sea Bromine Group, Beer Sheva, 5 Israel). PBBPA can also be prepared in situ by the addition of pentabromobenzyl monoacrylate to thermoplastic moulding compositions (EP-A 344 700). 10 Component C Preferred antimony compounds are antimony trioxide and/or antimony pentoxide, which are compounds which are generally known. 15 Component D Polycarbonates are preferably used in an amount of from 0 to 75 parts by weight, based on the total amount of the moulding composition. 20 Polycarbonates can very especially preferably be added in an amount of from 20 to 70 parts by weight, based on the total amount of the moulding composition. Aromatic polycarbonates and/or aromatic polyester carbonates according to component D that are suitable according to the invention are known from the 25 literature or can be prepared by processes which are 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 30 see, for example, DE-OS 3 077 934).

WU UU/30U13 r 1/.ry7t -7 The preparation of aromatic polycarbonates is carried out, for example, by reacting diphenols with carbonic acid halides, preferably phosgene, and/or with aromatic dicarboxylic acid dihalides, preferably benzenedicarboxylic acid dihalides, according to the boundary surface process, optionally with the use of chain 5 terminators, for example monophenols, and optionally with the use of branching agents having a functionality of three or more, for example triphenols or tetraphenols. Diphenols for the preparation of the aromatic polycarbonates and/or aromatic 10 polyester carbonates are preferably those of formula (I) ( )x(B)x OH 15 HO j -p in which A' represents a single bond, C,-C,-alkylene, C 2

-C

5 -alkylidene, C 5 -C,-cyclo 20 alkylidene, -0-, -SO-, -CO-, -S-, -SO 2 -, C-C, 2 -arylene, which may be condensed with further aromatic rings optionally containing hetero atoms, or a radical of the formula 25 (II) R a Ri o or a radical of formula (III) -8 CH \ - C (ll CCHa H3 5 the substituents B are each independently of the other C,-C.-alkyl, preferably C,-C 4 alkyl, especially methyl, halogen, preferably chlorine and/or bromine, C,-C 0 aryl, preferably phenyl, C 7 -C,,-aralkyl, phenyl-C,-C 4 -alkyl, preferably benzyl, 10 x are each independently of the other 0, 1 or 2, p is I or 0, and 15 R' and R' can be chosen individually for each Z and are each independently of the other hydrogen or C 1

-C

6 -alkyl, preferably hydrogen, methyl and/or ethyl, Z represents carbon, and 20 m represents an integer from 4 to 7, preferably 4 or 5, with the proviso that at at least one Z atom,

R

6 and R 7 are simultaneously alkyl. 25 Preferred diphenols are hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, bis(hydroxyphenyl)-C -C 5 -alkanes, bis(hydroxyphenyl)-C 5

-C

6 -cycloalkanes, bis (hydroxyphenyl) ethers, bis(hydroxyphenyl) sulfoxides, bis(hydroxyphenyl) ketones, bis(hydroxyphenyl)-sulfones and a,a-bis(hydroxyphenyl)-diisopropyl-benzenes, as 30 well as their derivatives brominated and/or chlorinated at the nucleus.

WO 00/36013 PCT/EP99/09494 -9 Especially preferred diphenols are 4,4'-diphenylphenol, 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' dihydroxydiphenylsulfone and their di- and tetra-brominated or -chlorinated 5 derivatives, such as, for example, 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-hydroxy phenyl)-propane. Special preference is given to 2,2-bis(4-hydroxyphenyl)-propane (bisphenol A). 10 The diphenols can be used individually or in the form of any desired mixtures. The diphenols are known from the literature or are obtainable by processes which are known from the literature. 15 Suitable chain terminators for the preparation of the thermoplastic, aromatic polycarbonates are, for example, phenol, p-chlorophenol, p-tert-butylphenol or 2,4,6-tribromophenol, as well as long-chained alkylphenols, such as 4-(1,3-tetra methylbutyl)-phenol according to DE-OS 2 842 005, or monoalkylphenols or 20 dialkylphenols having a total of from 8 to 20 carbon atoms in the alkyl substituents, such as 3,5-di-tert-butylphenol, p-isooctylphenol, p-tert-octylphenol, p-dodecyl phenol and 2-(3,5-dimethylheptyl)-phenol and 4-(3,5-dimethylheptyl)-phenol. The amount of chain terminators to be used is generally from 0.5 mol% to 10 mol%, based on the molar sum of the diphenols used in a particular case. 25 The thermoplastic, aromatic polycarbonates have mean weight-average molecular weights (Mw, measured, for example, by ultracentrifuge or scattered light measurement) of from 10,000 to 200,000, preferably from 20,000 to 80,000. 30 The thermoplastic, aromatic polycarbonates can be branched in a known manner, preferably by the incorporation of from 0.05 to 2.0 mol%, based on the sum of the WO 00/36013 PCT/EP99/09494 -10 diphenols used, of compounds having a functionality of three or more, for example compounds having three or more phenolic groups. Both homopolycarbonates and copolycarbonates are suitable. For the preparation of 5 copolycarbonates according to the invention as component A there may also be used from 1 to 25 wt.%, preferably from 2.5 to 25 wt.% (based on the total amount of diphenols to be used), of polydiorganosiloxanes having hydroxy-aryloxy terminal groups. Those compounds are known (see, for example, US patent 3 419 634) or can be prepared by processes which are known from the literature. The preparation of 10 polydiorganosiloxane-containing copolycarbonates is described, for example, in DE-OS 3 334 782. Preferred polycarbonates, in addition to the homopolycarbonates of bisphenol A, are the copolycarbonates of bisphenol A with up to 15 mol%, based on the molar sum of 15 diphenols, of diphenols other than those mentioned as being preferred or especially preferred, especially 2,2-bis(3,5-dibromo-4-hydroxyphenyl)-propane. Aromatic dicarboxylic acid dihalides for the preparation of aromatic polyester carbonates are preferably the diacid dichlorides of isophthalic acid, terephthalic acid, 20 diphenyl ether 4,4'-dicarboxylic acid and naphthalene-2,6-dicarboxylic acid. Special preference is given to mixtures of the diacid dichlorides of isophthalic acid and terephthalic acid in a ratio of from 1:20 to 20:1. 25 In the preparation of polyester carbonates, a carbonic acid halide, preferably phosgene, is additionally used concomitantly as difunctional acid derivative. There come into consideration as chain terminators for the preparation of the aromatic polyester carbonates, in addition to the monophenols already mentioned, 30 also their chlorocarbonic acid esters and the acid chlorides of aromatic WO 00/36013 PCT/EP99/09494 - 11 monocarboxylic acids, which may optionally be substituted by C 1

-C

22 -alkyl groups or by halogen atoms, as well as aliphatic C 2

-C

22 -monocarboxylic acid chlorides. The amount of chain terminators is in each case from 0.1 to 10 mol%, based in the 5 case of the phenolic chain terminators on moles of diphenols and in the case of monocarboxylic acid chloride chain terminators on moles of dicarboxylic acid dichlorides. The aromatic polyester carbonates may also contain aromatic hydroxycarboxylic 10 acids incorporated therein. The aromatic polyester carbonates may be either linear or branched in a known manner (see in this connection likewise DE-OS 2 940 024 and DE-OS 3 007 934). 15 There may be used as branching agents, for example, carboxylic acid chlorides having a functionality of three or more, such as trimesic acid trichloride, cyanuric acid trichloride, 3,3'-4,4'-benzophenone-tetracarboxylic acid tetrachloride, 1,4,5,8 naphthalenetetracarboxylic acid tetrachloride or pyromellitic acid tetrachloride, in amounts of from 0.01 to 1.0 mol% (based on dicarboxylic acid dichlorides used), or 20 phenols having a functionality of three or more, such as phloroglucinol, 4,6 dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptene, 2,4,4-dimethyl-2,4,6-tri-(4-hydroxy phenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-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-hydroxy 25 phenyl)-methane, 2,6-bis(2-hydroxy-5-methyl-benzyl)-4-methyl-phenol, 2-(4 hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane, tetra-(4-[4-hydroxyphenyl isopropyl]-phenoxy)-methane, 1,4-bis[4,4'-dihydroxytriphenyl)-methyl]-benzene, in amounts of from 0.01 to 1.0 mol%, based on diphenols used. Phenolic branching agents can be used initially with the diphenols, acid chloride branching agents can be 30 introduced together with the acid dichlorides.

WO 00/36013 PCT/EP99/09494 -12 The content of carbonate structural units in the thermoplastic, aromatic polyester carbonates can vary as desired. The content of carbonate groups is preferably up to 100 mol%, especially up to 5 80 mol%, especially preferably up to 50 mol%, based on the sum of ester groups and carbonate groups. Both the esters and the carbonates contained in the aromatic polyester carbonates can be present in the polycondensation product in the form of blocks or in a 10 randomly distributed manner. The relative intrinsic viscosity (lrei) of the aromatic polyester carbonates is in the range of from 1.18 to 1.4, preferably from 1.22 to 1.3 (measured on solutions of 0.5 g of polyester carbonate in 100 ml of methylene chloride solution at 25 0 C). 15 The thermoplastic, aromatic polycarbonates and polyester carbonates can be used alone or in any desired mixture with one another. The aromatic polycarbonates can be prepared by known processes, for example by 20 melt transesterification of a corresponding bisphenol with diphenyl carbonate and in solution from bisphenols and phosgene. The solution may be homogeneous (pyridine process) or heterogeneous (two-phase boundary surface process) (see H. Schnell, "Chemistry and Physics of Polycarbonates", Polymer Reviews, Vol. IX, p. 33 et seq., Interscience Publ. 1964). 25 The aromatic polycarbonates generally have mean molecular weights M of approximately from 10,000 to 200,000, preferably from 20,000 to 80,000 (calculated by gel chromatography after prior calibration). 30 Copolycarbonates within the scope of the invention are especially poly diorganosiloxane-polycarbonate block copolymers having a mean molecular weight WO 00/36013 PCT/EP99/09494 - 13 M of approximately from 10,000 to 200,000, preferably from 20,000 to 80,000 (calculated by gel chromatography after prior calibration) and having a content of aromatic carbonate structural units of approximately from 75 to 97.5 wt.%, preferably from 85 to 97 wt.%, and a content of polydiorganosiloxane structural 5 units of approximately from 25 to 2.5 wt.%, preferably from 15 to 3 wt.%, the block copolymers being prepared starting from polydiorganosiloxanes containing x,o-bis hydroxyaryloxy terminal groups and having a degree of polymerisation P, of from 5 to 100, preferably from 20 to 80. 10 The polydiorganosiloxane-polycarbonate block copolymers may also be a mixture of polydiorganosiloxane-polycarbonate block copolymers with conventional polysiloxane-free, thermoplastic polycarbonates, the total content of polydiorganosiloxane structural units in that mixture being approximately from 2.5 to 25 wt.%. 15 Such polydiorganosiloxane-polycarbonate block copolymers are characterised in that they contain in the polymer chain on the one hand aromatic carbonate structural units (1) and on the other hand polydiorganosiloxanes containing aryloxy terminal groups (2) 20 0 -O-Ar-O-C-O-Ar-O- (1), 25 R R - O-Ar-O - (- Si-0-)a-(~ SiO)b(- Si-O-);-Ar-O- (2), I I I R R R in which 30 Ar are identical or different aryl radicals from diphenols, and WO 00/36013 PCT/IEP99/09494 -14 R and R' are identical or different and represent linear alkyl, branched alkyl, alkenyl, halogenated linear alkyl, halogenated branched alkyl, aryl or halogenated aryl, but preferably methyl, 5 and the number of diorganosiloxy units n=a+b+c is from 5 to 100, preferably from 20 to 80. 10 Alkyl in formula (2) above is, for example, C 1

-C

2 0 -alkyl; alkenyl in formula (2) above is, for example, C 2

-C

6 -alkenyl; aryl in formula (2) above is C 6

-C

14 -aryl. In the above formula, halogenated means partially or completely chlorinated, brominated or fluorinated. 15 Examples of alkyls, alkenyls, aryls, halogenated alkyls and halogenated aryls are methyl, ethyl, propyl, n-butyl, tert-butyl, vinyl, phenyl, naphthyl, chloromethyl, perfluorobutyl, perfluorooctyl and chlorophenyl. Such polydiorganosiloxane-polycarbonate block copolymers are known, for 20 example, from US-A 3 189 662, US-A 3 821 325 and US-A 3 832 419. Preferred polydiorganosiloxane-polycarbonate block copolymers are prepared by reacting polydiorganosiloxanes containing a,o-bishydroxyaryloxy terminal groups together with other diphenols, optionally with the concomitant use of branching 25 agents in the usual amounts, for example by the two-phase boundary surface process (see in this respect H. Schnell, Chemistry and Physics of Polycarbonates, Polymer Rev. Vol. IX, page 27 et seq., Interscience Publishers New York 1964), the ratio of the difunctional phenolic reactants in each case being so selected that it results in the content of aromatic carbonate structural units and diorganosiloxy units according to 30 the invention.

WO 00/36013 PCT/EP99/09494 - 15 Such polydiorganosiloxanes containing a,o-bishydroxyaryloxy terminal groups are known, for example, from US 3 419 634. The thermoplastic moulding composition can contain up to 10 parts by weight, 5 especially from 1 to 8 parts by weight (based on a total weight of 100 parts by weight), of polyolefins. Suitable polyolefins are polymers of aliphatic unsaturated hydrocarbons, such as, for example, ethylene, propylene, butylene or isobutylene, which are obtained by conventional processes, for example radical polymerisation, and have mean weight-average molecular weights M, (measured by gel 10 chromatographic methods) of from 3,000 to 3,000,000. Both high-pressure and low pressure polyolefins can be used. Polyethylenes and polypropylenes are preferred. The moulding compositions may contain nucleating agents such as microtalc. The moulding compositions may also contain conventional additives, such as lubricants, 15 mould-release agents, processing stabilisers and anti-dripping agents (e.g. polytetrafluoroethylene) as well as colourings and pigments. The sheets produced by the extrusion or compression moulding process can be components from the electronics sector, which are desired to have good electrical 20 properties with, at the same time, good flame-resistant behaviour and good flowability and a high surface quality, without the thermoplastic matrix being damaged. There are accordingly used, for example, casing parts, plug boards and lamp holders, 25 as well as parts from the motor vehicle sector. Films produced from the moulding compositions may likewise be for the electronics sector, which films are desired to have good flame-resistant behaviour and good electrical properties, without the thermoplastic matrix being damaged. 30 WO 00/36013 PCT/EP99/09494 -16 Wire-coatings can be used, for example, for the electronics sector as well as in automotive manufacture; they are desired to have good flame-resistant behaviour, a high level of electrical properties, high resistance to chemicals and a high degree of thermal stability, without the thermoplastic matrix being damaged. 5 For the production of the films, sheets and wire-coatings, the components are mixed and compounded by means of an extruder in the usual manner at temperatures of approximately from 260*C to 320*C.

WO 00/36013 PCT/EP99/09494 -17 Examples Description of the test methods for testing moulded articles 5 Flame test according to UL 94 (IEC 707) Bending test according to ISO 178 Melt volume rate (volume flow index) according to ISO 1133 Table 1 10 The electrical properties are measured as follows: Electrical properties Test Units Standards Test conditions specimens Relative permittivity (dielectric constant) 100 Hz IEC 250 disk 80X2 Relative permittivity (dielectric constant) 1 MHz IEC 250 disk 80X2 Dielectric volume resistivity Ohm.cm IEC 93 disk 80X2 Specific surface resistivity Ohm IEC 93 disk 80X2 Dielectric strength kV/mm IEC 243-1 disk 118X2 Tracking index test solution A step IEC 112 disk 118X4 The components indicated in the Examples are mixed and compounded by means of 15 an extruder under conventional conditions, and are then processed to test specimens in an injection-moulding machine under conventional PBT processing conditions (composition temperature approximately 260*C). The test specimens are tested in respect of their properties.

WO 00/36013 PCT/EP99/09494 -18 The pentabromobenzyl polyacrylate (PBB-PA) used was Eurobrom FR 1025, Eurobrom B.V. (NL) Rijswijk-Netherlands. 5 Example 1 according to the invention 79.0 wt.% polybutylene terephthalate (PBT) (relative intrinsic viscosity 1.707-1.153, measured at T = 25*C in a 0.5% solution of phenol and o-dichlorobenzene, mixing ratio 1:1 parts by weight) 10 15.0 wt.% PBB-PA 5.2 wt.% antimony trioxide 0.8 wt.% additives Example 2 according to the invention 15 79.0 wt.% polybutylene terephthalate (PBT) (relative intrinsic viscosity 1.834-1.875, measured at T = 25*C in a 0.5% solution of phenol and o-dichlorobenzene, mixing ratio 1:1 parts by weight) 15.0 wt.% PBB-PA 20 5.2 wt.% antimony trioxide 0.8 wt.% additives WO 00/36013 PCT/EP99/09494 -19 Comparison Example 3 79.2 wt.% polybutylene terephthalate (PBT) (relative intrinsic viscosity 1.707-1.153, measured at T = 25*C in a 0.5% solution of phenol and o-dichlorobenzene, mixing ratio 1:1 parts 5 by weight) 15.0 wt.% epoxidised tetrabromobisphenol A 5.0 wt.% antimony trioxide 0.8 wt.% additives 10 Comparison Example 4 80.7 wt.% polybutylene terephthalate (PBT) (relative intrinsic viscosity 1.643-1.705, measured at T = 25*C in a 0.5% solution of phenol and o-dichlorobenzene, mixing ratio 1:1 parts by weight) 15 13.5 wt.% ethylene-bis-tetrabromophthalimide 5.0 wt.% antimony trioxide 0.8 wt.% additives Example 5 according to the invention 20 91.4 wt.% polybutylene terephthalate (PBT) (relative intrinsic viscosity 1.707-1.153, measured at T = 25*C in a 0.5% solution of phenol and o-dichlorobenzene, mixing ratio 1:1 parts by weight) 6.0 wt.% PBB-PA 25 1.8 wt.% antimony trioxide 0.8 wt.% additives WO 00/36013 PCT/EP99/09494 -20 Table 2 (results) Flame-protected thermoplastic moulding compositions Example Example Example Example Example 1 2 3 4 5 Properties Standards Units Accor- Accor- Compa- Compa- Accor ding to ding to rison rison ding to the the the invention invention invention Relative IEC 250 3.5 not tested not tested 3.4 not tested permittivity 100 Hz Relative IEC 250 3.5 not tested 3.2 3.2 not tested permittivity 1 MHz Dielectric IEC 93 Ohm.cm 4.5E+16 not tested > 10" > io1 not tested volume resistivity Specific IEC 93 Ohm 1.1E+17 not tested > 10"5 > io1 not tested surface resistivity Dielectric IEC 243 kV/mm 49 not tested 28 28 not tested strength Flame test UL 94 3.2 mm class VO V0 VO V0 VO 1.6 mm class VO V0 VO V0 V2 0.8 mm class VO V0 V0 VO not tested 0.4 mm class VO V0 cannot be cannot be not tested produced produced Bending test ISO 178 1 Flexural MPa 100 100 95 90 95 strength Flexural % 5.5 5.6 5.5 5.0 7.5 elongation Bending MPa 2800 2800 2700 2700 2600 modulus MVR ISO 1133 cm 3 /10 22 17 15* 20 19 260*C/2.16 min. kg load Tracking IEC 112 step 500 500 250 375 600 index I II * Comparison Example 3 is in comparison with Examples 1 and 5 5 The Table shows that the test specimens produced from the moulding compositions according to the invention have a markedly better creep resistance, a comparable or better flowability (MVR) and a higher level of mechanical properties than the WO 00/36013 PCT/EP99/09494 -21 comparison test specimens. The moulding compositions according to the invention can also be processed to test specimens having thin wall thicknesses, so that an especially good behaviour in fire is achieved here. Comparison Examples 3 and 4 cannot be processed to test specimens having a thickness of 0.4 mm according to the 5 flame test description. The indicated components can also be mixed and processed to films in a film extrusion machine under conventional PBT processing conditions (composition temperature approximately 250*C). 10 Description of the test methods for testing films Flame test according to UL 94 (IEC 707) The tests according to UL 94V and UL 94 VTM can be used for films. Sections 8.1 15 and 11.1 of UL 94 indicate the criteria for the selection of the test method. Tensile test according to ISO 1184. Films according to the invention having thicknesses in the range of from 0.1 mm to 0.8 mm are produced and tested in the flame test according to UL 94. 20 Example 1 according to the invention processed to a film: With a film thickness of 0.6 mm, a V-0 was obtained in the test according to UL 94V. With a film thickness of 0.1 mm, the test according to UL 94 VTM is carried out and results in VTM-0. 25 Example 2 according to the invention: Films according to the invention having thicknesses in the range of from 0.125 mm to 0.75 mm are produced and tested in the flame test according to UL 94.

WO 00/36013 PCT/EP99/09494 -22 Table 3 Results of the flame test (Example 2) Film thickness/mm Test according to UL 94 V UL 94 VTM 0.125 not tested VTM-0 0.250 V-0 VTM-0 0.375 V-0 VTM-0 0.750 V-0 not tested The stress at break and breaking elongation and the modulus of elasticity of those 5 films are determined in the tensile test according to ISO 1884. Table 4 Results of the mechanical properties (Example 2) Thickness Stress at break Breaking elongation Modulus of elasticity mm MPa % MPa longitudinal transverse longitudinal transverse longitudinal transverse 0.125 37 41 3.4 12.2 2550 2500 0.175 46 36 3.4 17.6 2590 2515 0.250 44 43 6.4 5.4 2730 2620 0.375 43 46 12.3 10.0 2920 2910 0.450 45 50 5.2 4.2 3070 2910 0.500 50 48 4.5 8.6 3100 3140 0.625 52 52 10.0 3.8 3190 3300 0.750 52 51 3.9 7.3 3420 3290 WO 00/36013 PCT/EP99/09494 - 23 Comparison Example 3 The product could not be processed to films (tearing, surfaces greatly damaged). Comparison Example 4 5 The product could not be processed to films (tearing, surfaces greatly damaged). In contrast to the comparison tests, the moulding compositions according to the invention can be processed to films which have a high surface quality, especially in respect of shine and uniformity. At the same time, excellent behaviour in fire is 10 achieved, while the level of mechanical properties is high.

Claims (8)

1. Extrudates and moulded articles produced by the compression moulding process, based on thermoplastic moulding compositions containing 5 A) from 55 to 97.7 parts by weight of polyalkylene terephthalate, B) from 2 to 30 parts by weight of pentabromobenzyl polyacrylate, 10 C) from 0.3 to 12 parts by weight of antimony compound(s), and D) from 0 to 90 parts by weight of polycarbonate and/or polyester carbonate, 15 wherein the sum of A) + B) + C) + D) is 100 and up to 10 parts by weight of polyalkylene terephthalate can be replaced by polyolefins.

2. Extrudates and moulded articles produced by the compression moulding process according to claim 1, based on thermoplastic moulding compositions 20 containing A) from 60 to 95.5 parts by weight of polyalkylene terephthalate, B) from 3 to 25 parts by weight of pentabromobenzyl polyacrylate, 25 C) from 0.5 to 10 parts by weight of antimony compound(s), and D) from 0 to 75 parts by weight of polycarbonate and/or polyester carbonate. 30 WO 00/36013 PCT/EP99/09494 -25

3. Extrudates and moulded articles produced by the compression moulding process according to claim 1, based on thermoplastic moulding compositions containing 5 A) from 70 to 95 parts by weight of polyalkylene terephthalate, B) from 4 to 20 parts by weight of pentabromobenzyl polyacrylate, C) from 1 to 8 parts by weight of antimony compound(s), and 10 D) from 0 to 75 parts by weight of polycarbonate and/or polyester carbonate.

4. Extrudates and moulded articles produced by the compression moulding 15 process, based on thermoplastic moulding compositions according to any of the preceding claims, wherein the thermoplastic moulding compositions contain conventional additives.

5. Extrudates and moulded articles produced by the compression moulding 20 process, based on thermoplastic moulding compositions according to claim 5, wherein the additives are selected from at least one additive from the group consisting of nucleating agents, lubricants, mould-release agents, processing stabilisers, colourings, pigments and anti-dripping agents. 25

6. Films, sheets and wire-coatings according to any of the preceding claims.

7. Use of thermoplastic moulding compositions according to any of claims 1 to 5 in the production of extrudates and moulded articles produced by the compression moulding process having improved properties in respect of 30 breaking elongation and stress at break and surface quality. WO 00/36013 PCT/EP99/09494 -26

8. Use according to claim 7 in the production of films, sheets and wire-coatings.