Glass fiber filled thermoplastic flame retardant composition

Abstract

The present invention relates to a thermoplastic composition comprising, based on the weight of the thermoplastic composition, from 79 - 94 wt.% of aromatic polycarbonate, from 5 - 25 wt.% of glass fibers, preferably non-bonding glass fibers, from 0.10 - 0.50 wt.% of halogen free flame retardant salt, from 0.2 - 5 wt.% of a polysiloxane, from 0 – 2 wt.% of anti-drip agent, and from 0 - 3 wt.% of further components, wherein the sum of the components is 100 wt.% and wherein the thermoplastic composition has or is selected to have a UL94 rating of V0 performed at 1.5 mm. The invention moreover relates to an article comprising the thermoplastic composition.

Description

[0001] TITLE glass fiber filled thermoplastic flame retardant composition

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a thermoplastic composition and articles obtained therefore.

[0004] Background

[0005] Glass fiber filled polycarbonates are used for example in electrical and electronics applications, such as MCE (Micro Circuit Engineering) protection, TV enclosures, domestic wired devices, microelectronics. These applications are currently facing down gauging and miniaturization with design constraints in flame resistance and processing (mould filling). Especially for new applications in 5G equipment & microelectronics, there is a need for new glass-fiber filled flame retardant polycarbonate compositions for replacing metal or glass-fiber filled polyamide or glassfiber filled PBT materials. The main difficulty is obtaining a UL 94 V-0 rating for very low thickness, such as at 1.5 mm or 1.2 mm, with flame retardants that are halogen free (including PFAS free), or at least free of bromine and chlorine.

[0006] EP2471854 discloses q glass fiber reinforced polycarbonate resin composition comprising (A) a glass fiber reinforced polycarbonate; (B) a mixture of two kinds of organic silicone based compounds comprising (b1) a siloxane based compound and (b2) a silicone based resin; (C) a metal salt based flame retardant; and (D) a fluorinated polyolefin based resin. All the examples in this reference rely on the use of Rimar salt (potassium perfluorobutane sulfonate), which is a fluorine containing material.

[0007] CN103709708 discloses a high-flow, glass-reinforced halogen-free flame-retardant polycarbonate material, characterized in that the material is prepared from the following components and parts by weight: polycarbonate 50-90, glass fiber 10-30, flow modifier 0-10, compatibilizer 0-10, halogen-free flame retardant 0.1-1 , flame retardant synergist 0-2, lubricant 0.1- 1 and antioxidant 0.1-1 . This reference does not teach or suggest how to formulate compositions that can achieve a UL94 rating of V0 at 1 ,5mm or even 1 ,2mm. W02007 / 094932 discloses a flame retardant composition comprising (i) 100 parts by weight of polycarbonate; (ii) from about 0.0001 parts to about 0.2 parts by weight of an aromatic sulfone sulfonate; (iii) from about 0.002 parts to about 0.2 parts by weight of an aromatic sulfonate; (iv) optionally from about 0.05 parts to about 2 parts by weight of a siloxane oligomer, wherein a molded sample of the composition is able to achieve a UL 94 V0 rating at a thickness of 3.0 mm.

[0008] Objects

[0009] It is an object of the present invention to provide an improved glass-fibre reinforced thermoplastic composition having excellent mechanical and flammability properties. In particular, it is object of the present invention to provide thermoplastic compositions that are suitable for thin applications and that are free of bromine and chlorine.

[0010] STATEMENT OF THE INVENTION

[0011] In a first aspect, the invention relates to a thermoplastic composition comprising, based on the weight of the thermoplastic composition, a) from 79 - 94 wt.% of aromatic polycarbonate, b) from 5 - 25 wt.% of glass fibers, preferably non-bonding glass fibers, c) from 0.10 - 0.50 wt.% of halogen free flame retardant salt, preferably a alkali metal salt of an aromatic sulfonate, more preferably the potassium salt of diphenyl sulfone sulfonate (KSS) or the sodium salt of toluene sulfonate (NaTS) or a combination thereof, d) from 0.2 - 5 wt.% of a polysiloxane, e) from 0 - 2 wt.%, preferably 0.2 - 1 wt.% of an anti-drip agent, and f) from 0 - 3 wt.% of further components, wherein the sum of components a) - f) is 100 wt.% and wherein the thermoplastic composition has or is selected to have a UL94 rating of V0 performed at 1.5 mm, preferably performed at 1.2 mm. In a second aspect, the invention relates to an article comprising said thermoplastic composition.

[0012] Corresponding embodiments of the thermoplastic composition are also applicable for the article according to the present invention.

[0013] DETAILED DESCRIPTION

[0014] The present invention is elucidated below with a detailed description.

[0015] List of definitions

[0016] The following definitions are used in the present description and claims to define the stated subject matter. Other terms not cited below are meant to have the generally accepted meaning in the field.

[0017] “non-bonding glass fibers” as used in the present description means: glass fibers that have been coated with a sizing composition that is results in poor adhesion of the coated glass fibers to the polycarbonate matrix, in other words that are non-bonding with respect to the aromatic polycarbonate. The individual fibers of the glass fiber filler may not demonstrate an affinity towards the polymer matrix. The term “glass” here refers generally to a material, natural or synthetic, which contains silicon dioxide (SiO2) or silica as its main material.

[0018] “bonding glass fibers” as used in the present description means: glass fibers that have been coated with a sizing composition that is results in good / improved adhesion of the coated glass fibers to the polycarbonate matrix, in other words that are bonding with respect to the aromatic polycarbonate. The individual fibers of glass fiber filler may exhibit affinity toward the polycarbonate resin matrix. This affinity may be attributed to the glass sizing, among a number of other forces.

[0019] “halogen free flame retardant salt” as used in the present description means: a flame retardant in the form of a salt that contains to halogen atoms, in other words that is free of bromine, free of chlorine, free of fluorine and free of iodine. There are flame retardants that are free of bromine and free of chlorine but that do comprise fluorine, such as Rimar Salt (potassium salt of the fluorinated alkyl sulfonate perfluorobutane sulfonate). These are not according to the present invention. The present invention relates Thermoplastic composition

[0020] The thermoplastic composition of the present invention comprises the following components: a) one or more aromatic polycarbonates, b) one or more glass fibers’c) one or more halogen free flame retardant salts, and d) one or more polysiloxanes. Optionally, the thermoplastic composition further comprises e) one or more anti-drip agents and f) one or more further components. The sum of components a) - f) is 100 wt.% of the thermoplastic composition.

[0021] UL rating

[0022] The thermoplastic composition has or is selected to have a UL94 rating of VO performed at 1.5 mm, preferably performed at 1.2 mm.

[0023] An important requirement of the present thermoplastic composition is that it has excellent properties in view of safety / flammability. The UL 94 is the Standard for Safety of Flammability of Plastic Materials for Parts in Devices and Appliances testing, being a plastics flammability standard of the United States. This test determines the material's tendency to either extinguish or spread the flame once the specimen has been ignited. According to the present invention, the rating must be a V-0 (V-zero) which states that burning stops within 10 second on a vertical specimen. UL ratings can be measured at various thicknesses and this can drastically change the rating. This thicker the specimen, the better the UL rating. For the present invention, it is required that a V-0 rating is obtained for a thin specimen, having a thickness of 1.5 mm, even more preferably for a thickness of 1.2 mm. This allows the present thermoplastic compositions to be used for thin applications.

[0024] HDT

[0025] The Heat Deflection Temperature or Heat Distortion Temperature (HDT) is a measure of a polymer's resistance to alteration under a given load at an elevated temperature. It is the temperature at which a polymer deforms under a specified load. Other names for this are 'deflection temperature under load' (DTUL) or 'heat deflection temperature under load (HDTUL). The heat distortion temperature (HDT) was measured according to ISO 75 / Af, 80*10*4 sp=64mm. In an embodiment, the thermoplastic composition has or selected to have a heat distortion temperature (HDT) of at least 130 °C, preferably at least 132 °C.

[0026] Specific embodiment

[0027] In a specific embodiment, the thermoplastic composition comprising, based on the weight of the composition, a) from 79 - 94 wt.% of aromatic polycarbonate (preferably 79.0 - 94.0 wt.%), b) from 7 - 13 wt.% of non-bonding glass fibers (preferably 7.0 - 13.0 wt.%), c) from 0.15 - 0.30 wt.% of halogen free flame retardant salt, preferably the potassium salt of diphenyl sulfone sulfonate (KSS), d) from 0.8 - 1 .5 wt.% of a polysiloxane e) from 0.2 - 1 wt.% of an anti-drip agent (preferably 0.20 - 1 .0 wt.%), f) from 0 - 3 wt.% of further components (preferably 0.0 - 3.0 wt.%).

[0028] Aromatic polycarbonate

[0029] The thermoplastic composition comprises (as component a) one or more aromatic polycarbonates in an amount of between 79 to 94 wt.% based on the total weight of the thermoplastic composition.

[0030] In an embodiment, the thermoplastic composition comprises as aromatic polycarbonate one or more bisphenol-A polycarbonates, preferably bisphenol A- homopolymers. In an embodiment, the thermoplastic composition comprises no further polymer components.

[0031] In an embodiment, the thermoplastic composition has a melt volume rate (MVR) of between 6 and 20 cc / 10 min, such as between 7 and 20 cc / 10 min, preferably between 10 and 15 cc / 10 min measured according to ISO 1133 at 300° C under a 1 .2 kg load.

[0032] In an embodiment, the aromatic polycarbonate is a blend of two or more aromatic polycarbonates having different weight average molecular weights, preferably a blend of a first polycarbonate having a melt volume rate (MVR) of between 3 and 10 cc / 10 min and a second polycarbonate having a melt volume rate (MVR) of between 20 and 35 cc / 10 min measured according to ISO 1133 at 300° C under a 1 .2 kg load.

[0033] Even more preferably, the aromatic polycarbonate is a blend of a first bisphenol-A- polycarbonate homopolymer having a melt volume rate (MVR) of between 3 and 10 cc / 10 min and a second bisphenol-A-polycarbonate homopolymer having a melt volume rate (MVR) of between 20 and 35 cc / 10 min measured according to ISO 1133 at 300° C under a 1 .2 kg load.

[0034] In an embodiment the aromatic polycarbonate is a blend of two polycarbonate, preferably two bisphenol-A-polycarbonate homopolymers, more preferably having a different MVR as discussed directly above, wherein the ratio of the two polycarbonates (also called split ratio) is between 10:90 and 90:10, such as between 20:80 and 80:20, or between 30:70 and 70:30 or between 40:60 and 60:40, for example 50:50.

[0035] Glass fibers

[0036] The thermoplastic composition comprises (as component b) one or more glass fibers in an amount of between 5 - 25 wt.% based on the total weight of the thermoplastic composition. In an embodiment, the glass fibers are present in an amount of between 5 and 15 wt.%, preferably between 7 and 13 wt.%.

[0037] In an embodiment, the present composition comprises non-bonding glass fibers. In an embodiment, substantially all glass fibers of the thermoplastic composition are nonbonding glass fibres.

[0038] The glass fibers may be selected from E-glass, S-glass, AR-glass, T-glass, D-glass and R-glass, in particular from E-glass, S-glass, and combinations thereof, more in particular an E-glass or EC glass. The glass fibers can be made by standard processes, e.g., by steam or air blowing, flame blowing, and mechanical pulling. Exemplary glass fibers for polycarbonate reinforcement are made by mechanical pulling. In preparing the non-bonding or bonding glass fibers, a number of filaments can be formed simultaneously, sized with the coating agent and then bundled into what is called a strand. Alternatively the strand itself may be first formed of filaments and then sized. The amount of sizing employed is generally that amount which is sufficient to bind the glass filaments into a continuous strand and ranges from about 0.1 to about 5 wt. %, about 0.1 to 2 wt.% based on the weight of the glass fibers. Generally, this may be about 1 .0 wt. % based on the weight of the glass filament.

[0039] The glass fibers may be continuous or chopped. In some examples, the glass fibers are chopped glass fibers in the form of chopped strands, e.g. having a length of about 0.3 mm to about 10 cm, specifically about 0.5 mm to about 5 cm, and more specifically about 1 .0 mm to about 2.5 cm, e.g. between 0.2 mm to 20 mm or from about 0.2 mm to about 10 mm.

[0040] The glass fibers may have a round (or circular), flat, or irregular cross-section. The width or diameter of the non-bonding glass fiber may be from about 1 to about 20 pm, or from about 5 to about 20 pm, or from about 5 to about 15 pm.

[0041] Flame retardant salt

[0042] The thermoplastic composition comprises (as component c) one or more halogen free flame retardant salt in an amount of between 0.10 and 0.50 wt.% based on the total weight of the thermoplastic composition.

[0043] Preferably, the flame retardant salt is an alkali metal salt of an aromatic sulfonate, such as the potassium salt. In an embodiment, the flame retardant salt is the potassium salt of diphenyl sulfone sulfonate (KSS) or the sodium salt of toluene sulfonate (NaTS) or a combination thereof. in an embodiment to bromo-free, chloro-free and per-fluoroalkylsulfonate-free salts.

[0044] Polysiloxane

[0045] The thermoplastic composition comprises (as component d) one or more polysiloxanes in an amount of between 0.2 and 5 wt.% based on the total weight of the thermoplastic composition. In case more than one polysiloxanes are present, the amount cited above is the combined amount of all polysiloxanes.

[0046] In an embodiment, the polysiloxane is a homopolymer of siloxanes, or silicones, that comprise of a silicon-oxygen backbone with organic groups, for example methyl groups, attached to the silicon atoms.

[0047] In an embodiment, the polysiloxane is in liquid form. In an embodiment, the polysiloxane according to the present invention does not include polysiloxane that is coated on or otherwise supported on a solid material, such as polysiloxane-treated talc.

[0048] Anti-drip agent

[0049] The thermoplastic composition optionally comprises (as component e) one or more anti-drip agents in an amount of between 0 and 2 wt.%, preferably between 0.2 and 1 wt.% based on the total weight of the thermoplastic composition.

[0050] In an embodiment, the anti-drip agent is polytetrafluoroethylene (PTFE) or polytetrafluoroethylene (PTFE)-encapsulated styrene-acrylonitrile copolymer (TSAN). These types of anti-drip agents are so-called PFAS compounds. Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that are used in may products but are currently under review for environmental reasons. Decreasing the amount of PFAS is desirable.

[0051] Further components

[0052] The thermoplastic composition optionally comprises (as component f) one or more further components in an amount of between 0 and 3 wt.% based on the total weight of the thermoplastic composition.

[0053] In an embodiment, the further components comprise a plasticizer, an anti-static agent, an impact modifier, a colorant, an antioxidant, a mould release agent, an UV absorber, a lubricant, or a blowing agent, or a combination of two or more thereof. Article / applications

[0054] In an embodiment, the article is selected from the group consisting of aerospace and aircraft components, (electronic) vehicle components, components for electrical & electronics, components for energy production and storage, components for communication infrastructure or infrastructure, articles for sports and recreation, components for architecture, and components for industry.

[0055] Examples or aerospace and aircraft components are rudder, elevator, fuselage, landing gear doors, leading and trailing edge wing components, fuel tanks and floors. Examples of (electronic) vehicle components are automotive component, such as air deflectors and spoilers, air-intake manifolds, battery casings and covers, bumpers and bumper beams, cylinder head (e.g. valve, rocker, cam) covers, frames for windows / sunroofs, front-end grill opening panels, headlamp housings for forwardfacing headlamps, heat shields (e.g. engine, transmission), pillars and coverings, or components of marine vessels, such as superyachts, racing yachts workboats, and leisure crafts, such as boat hulls, frames, keels, masts, poles and boom, carbon winch drums, shafting, bearings, propellers, commercial hatch covers, exhausts, and topside structures.

[0056] Examples of electrical and electronics components are electrical enclosures, electrical outlets, battery enclosure cases - e.g. for smart phones and computers or other electrical equipment-, microprocessors, (micro or miniature) circuit breakers, circuit protection, personal and (5G) industrial computer casing or parts.

[0057] Examples of components for energy production and storage are turbine and rotor blades for land-based and off-shore wind turbines, multifunctional energy storage composites (MESO), hydrogen tanks for aerospace, hydrogen fuel cells, and battery cells.

[0058] Examples of components for communication infrastructure are components for 5G infrastructure and mobiles, such as antenna systems. Examples of components for infrastructure are components for reinforcing concrete, for example of bridges, or to replace steel rebars, e.g. in bridge decks or other outdoor concrete flooring structures.

[0059] Examples of sports and recreation articles are fishing rods, tennis racquets, spars / shafts for kayak paddles, windsurfing masts and boards, hockey sticks, kites, and bicycle handlebars, as well as in niche applications, such as fairings for recumbent bikes.

[0060] Examples of components for architecture are interior or exterior building panels, pipes, ducts and tank installations.

[0061] Examples of industrial components are pipes, ducts and tank installations for i) (chemical) manufacturing plants, ii) oil & gas mining, treatment and transport, or iii) (waste)water treatment.

[0062] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. The scope of the present invention is defined by the appended claims. One or more of the objects of the invention are achieved by the appended claims.

[0063] EXAMPLES

[0064] The present invention is further elucidated based on the Examples below which are illustrative only and not considered limiting to the present invention.

[0065] Table 1: materials were used in the Examples

[0066]

[0067] Methods Melt volume rates (MVR) were measured in accordance with the ISO 1133 standard at 300° C under a load of 1.2 kg with a dwell time of 5 minutes. The granules were dried for 4 hours at 100° C. MVR is reported in cubic centimetres (cc or cm3) of polymer melt / 10 minutes.

[0068] Flame rating (V0 flammability tests) were performed following the procedure of Underwriter's Laboratory Bulletin 94 entitled “Tests for Flammability of Plastic Materials, UL94. ” According to this procedure, materials may be classified as V0, V1 or V2 on the basis of the test results obtained for samples of a specified thickness. The samples are made according to the UL94 test procedure using standard ASTM moulding criteria. It should be noted that when a V0 performance is given for a specified thickness, V0 performance is also obtained at greater thicknesses. Samples were burned in a vertical orientation after aging for 48 hours at 23 ± 2 °C, 50% relative humidity or 168 hours at 70° C. The criteria for each of the flammability classifications tested are described below.

[0069] V0: In a sample placed so that its long axis is 180 degrees to the flame, the maximum period of flaming and / or smouldering after removing the igniting flame does not exceed 10 seconds and none of the vertically placed samples produces drips of burning particles that ignite absorbent cotton, and no specimen burns up to the holding clamp after flame or after glow. The criteria for flammability classifications according to V-0 are <10 seconds individual flame time and <50 seconds total flame time of 5 specimens.

[0070] V1 , V2: In a sample placed so that its long axis is 180 degrees to the flame, the average period of flaming and / or smouldering after removing the igniting flame does not exceed 30 seconds and, for a V1 rating, none of the vertically placed samples produces drips of burning particles that ignite absorbent cotton. The V2 standard is the same as V1 , except that flaming drips that ignite the cotton are permitted. The criteria for flammability classifications according to V-1 are <20 seconds individual flame time and <250 seconds total flame time of 5 specimens. The criteria for flammability classifications according to V-2 are <30 seconds individual flame time and <250 seconds total flame time of 5 specimens.

[0071] Heat deflection temperature (HDT) measurements were performed on 80mm *10mm *4 mm un-annealed bars with a span length of 64 mm in accordance with ISO 75 / Af-1 :2020 (method A and flat wise) at 1.8 MPa and 120 degrees Celsius per hour and are reported in degrees Celcius.

[0072] Un-notched Izod impact (“UNH”) measurements were performed on 80mm *10mm *4 mm bars at 23° ± 2°C in accordance with the ISO 180:2019 standard with a 11 Joule Hammer and are reported in units of kJ / m2.

[0073] Tensile modulus (TM) measurements were performed according to ISO 527-1 :2019 standard with a speed of 1 mm / min (Extensometer) and 5 mm / min (testing speed) in a stress-strain test by a Universal Testing Machine (UTM) and are reported in units of MPa.

[0074] Extrusion profile for blends

[0075] A ZSK-25 compounder was used with a 1040 mm, 3 mm die with two strand options, a die temperature of 280 °C. The following temperature profile was used: Zone 1 (feeding) 40 °C; Zone 2 170 °C; Zone 3 220 °C; Zone 4 240 °C; Zones 5-6 255 °C; Zone 7 270 °C; Zones 8-10 280 °C. The screw speed was 300 rpm, the throughput 9- 10 kg / hr, the torque 60-65%, with a vacuum 1 of -0.08 MpA with the side feeder in zone 6.

[0076] The moulding profile of glass fiber filled Polycarbonate FR resin is shown in the Table below.

[0077] Table 2: moulding profile.

[0078] Effect of use of polysiloxane

[0079] To show the effect of the use of polysiloxane as synergist in combination with the halogen free flame retardant in the glass fiber filled thermoplastic composition five thermoplastic compositions were prepared: comparative example 1 (CE1) without any flame retardant or synergist; comparative example 2 (CE2) with KSS as flame retardant but without synergist; comparative example 3 (CE3) with KSS as flame retardant and kaoline as synergist; comparative example 4 (CE4) with KSS as flame retardant and PPZ as synergist, and Inventive example 1 (IE1) with KSS as flame retardant and polysiloxane as synergist. The three compositions were tested for UN 11 , HDT, UL-94 at 1.5 mm and at 1.2 mm and the MVR was measured. Table 3 below shows the composition as well as the results.

[0080] Table 3. Effect of use of polysiloxane as synergist and other synergists

[0081]

[0082] The above clearly shows that the combination of a halogen free flame retardant (KSS) and polysiloxane as a synergist gives a very robust flame retardancy with a V-0) value for 1.2 mm and with a high HDT and with a reasonably good flow.

[0083] Amount of flame retardant material

[0084] Experiments were carried out to optimize the quantity of the flame retardant material, in other words, to reduce the amount but still obtain good FR performance.

[0085] To show the effect of the quantity of the flame retardant material in the glass fiber filled thermoplastic composition thermoplastic compositions were prepared: Inventive example 3a (IE3a) has 0.2 wt.% of KSS, Inventive example 4 (IE4) has 0.3 wt.% of KSS. The three compositions were tested for UN 11 , HDT, UL-94 at 1 .5 mm and at 1 .2 mm and the MVR was measured.

[0086] In addition, compositions were prepared without the presence of a UV stabilizer (STAB 2). The compositions (IE2 and I E3b) were tested for UN 11 , HDT, UL-94 at 1 .5 mm and at 1 .2 mm and the MVR was measured. Table 4 below shows the composition as well as the results for all of these examples.

[0087] Table 4. Effect of use of UV stabilizer and amount of flame retardant.

[0088] The above clearly shows that flame retardant needs to be present in an amount of more than 0.1 wt.% in order to provide the required UL94 rating.

[0089] Evaluation of different blends of polycarbonate

[0090] Experiments were carried out to optimize the type of polycarbonate(s). To show if there is an effect of the type of polycarbonate, five thermoplastic compositions were prepared: Inventive examples 5a-c (IE5a, IE5b, and IE5c) for interfacial PC and Inventive examples 6a-b (IE6a, and IE6b) for melt PC. Three different blends of interfacial PC were tested, with a different ratio of high MVR and low MVR components, one of the two compositions further comprising a UV stabilizer. Two different blends of melt PC were tested, one with a quenching agent and one without a quenching agent. The five compositions were tested for UNII, HDT, UL-94 at 1.5 mm and at 1.2 mm and the MVR was measured. The compositions and results are shown in Table 5 below.

[0091] Table 5. Effect of use of different PC blends. The above clearly shows that all blends of both interfacial as well as melt PC provide excellent flame retardancy results as well as high HDT for a wide range of MVR values.

[0092] Optimization of level of anti-drip agent Experiments were carried out to optimize the level of the anti-drip agent. To show the effect of the level of the anti-drip agent, four thermoplastic compositions were prepared: Inventive examples IE7a-d (IE7a, IE7b, IE7c, and IE7d). The four compositions were tested for UN 11 , HDT, UL-94 at 1 .5 mm and at 1 .2 mm and the MVR was measured.

[0093] Table 6. Effect of use of different amounts of anti-drip agent. The above clearly shows that even with lower levels of anti-drip agent, sufficient to good flame retardancy results as well as high HDT can be obtained.

[0094] Effect of different types of polysiloxanes Experiments were carried out to optimize the type of polysiloxane. To show the effect of different types of polysiloxanes, six thermoplastic compositions were prepared: Inventive examples 8a-b (IE8a, IE8b), Inventive examples 9a-b (IE9a, IE9b), and Inventive examples 10a-b (IE10a, IE1 Ob). The six compositions were tested for UNII, HDT, UL-94 at 1 .5 mm and at 1 .2 mm and the MVR was measured.

[0095] Table 7. Effect of use of different types of polysiloxanes.

[0096] The above clearly shows that with SG 1 and SG 2, both being polymers of DMS, excellent flame retardancy as well as high HDT can be obtained for both types of PC. Composites with SG 1 , shows ductile behaviour with both interfacial and melt PC. Composites with SG 2 and SG 3, shows ductile behaviour only with interfacial PC.

Claims

CLAIMS1. A thermoplastic composition comprising, based on the weight of the thermoplastic composition, a) from 79 - 94 wt.% of aromatic polycarbonate, b) from 5 - 25 wt.% of glass fibers, preferably non-bonding glass fibers, c) from 0.10 - 0.50 wt.% of halogen free flame retardant salt, preferably a alkali metal salt of an aromatic sulfonate, more preferably the potassium salt of diphenyl sulfone sulfonate (KSS) or the sodium salt of toluene sulfonate (NaTS) or a combination thereof, d) from 0.2 - 5 wt.% of a polysiloxane, e) from 0 - 2 wt.%, preferably 0.2 - 1 wt.% of an anti-drip agent, and f) from 0 - 3 wt.% of further components, wherein the sum of components a) - f) is 100 wt.% and wherein the thermoplastic composition has or is selected to have a UL94 rating of V0 performed at 1.5 mm, preferably performed at 1.2 mm.

2. The thermoplastic composition according to claim 1 , having or selected to have a heat distortion temperature (HDT) of at least 130 °C, preferably at least 132 °C.

3. The thermoplastic composition according to claim 1 or 2, having or selected to have a melt volume rate (MVR) of below 10 cc / 10min.

4. The thermoplastic composition according to any one of the preceding claims, wherein the aromatic polycarbonate is a bisphenol-A polycarbonate, preferably bisphenol A-homopolymer, preferably wherein the thermoplastic composition comprises as further components no polymer components.

5. The thermoplastic composition according to any one of the preceding claims, wherein the glass fibers are present in an amount of between 5 - 15 wt.%, preferably between 7 - 13 wt.%.

6. The thermoplastic composition according to any one of the preceding claims, wherein the polysiloxane is a homopolymer of siloxane, preferably of dimethylsiloxane.

7. The thermoplastic composition according to any one of the preceding claims, wherein the further components comprise a plasticizer, an anti-static agent, an impact modifier, a colorant, an antioxidant, a mould release agent, an UV absorber, a lubricant, or a blowing agent, or a combination of two or more thereof.

8. The thermoplastic composition according to any one of the preceding claims, having a melt volume rate (MVR) of between 6 and 20 cc / 10 min, preferably between 7 and 20 cc / 10 min, more preferably between 10 and 15 cc / 10 min measured according to ISO 1133 at 300° C under a 1 .2 kg load.

9. The thermoplastic composition according to any one of the preceding claims, wherein the aromatic polycarbonate is a blend of two or more aromatic polycarbonates having different weight average molecular weights, preferably a blend of a first polycarbonate having a melt volume rate (MVR) of between 3 and 10 cc / 10 min and a second polycarbonate having a melt volume rate (MVR) of between 20 and 35 cc / 10 min measured according to ISO 1133 at 300° C under a 1 .2 kg load.

10. The thermoplastic composition according to any one of the preceding claims, comprising, based on the weight of the composition, a) from 79 to 94 wt.% of aromatic polycarbonate, b) from 7 - 13 wt% of non-bonding glass fibers, c) from 0.15 - 0.30 wt.% of halogen free flame retardant salt, preferably the potassium salt of diphenyl sulfone sulfonate (KSS), d) from 0.8 - 1 .5 wt.% of a polysiloxane e) from 0.2 - 1 wt.% of an anti-drip agent, f) from 0 - 3 wt.% of further components.

11. An article comprising the thermoplastic composition of claims 1 - 10.

12. The article according to claim 11 , wherein the article is wherein the article is selected from the group consisting of aerospace and aircraft components, (electronic) vehicle components, components for electrical & electronics, components for energy production and storage, components for communication infrastructure or infrastructure, articles for sports and recreation, components for architecture, and components for industry.

Images