Flame retardant thermoplastic composition

Abstract

The invention relates to a thermoplastic composition comprising, based on the weight of the composition, A) from 65 to 85 wt.% of polycarbonate; B) from 4 to 7 wt.% of flame retardant comprising phosphazene; C) from 5 to 25 wt.% of glass fibers; D) from 0.5 to 2 wt.% of polysiloxane; and E) from 0 to 2 wt.% of other components, wherein - the sum of the components (A) to (E) is 100 wt.%, - the composition does not comprise a per-fluoroalkyl or a polyfluoroalkyl substances, and - the composition has or is selected to have a UL94 flame retardancy rating of VO measured on an injection molded sample having a thickness of 1.0 mm.

Description

[0001] 25POLYOOQ4-WO-ORD 1

[0002] FLAME RETARDANT THERMOPLASTIC COMPOSITION

[0003] The present invention relates to a flame retardant polycarbonate composition.

[0004] Flame retardant polycarbonate compositions are known per se and many are based on the use of fluorine containing materials like potassium-perfluorobutane sulphonate (also known as Rimar salt) and polytetrafluoroethylene as an anti-dripping agent.

[0005] US 2015 / 0011688 discloses a blended thermoplastic composition comprising (i) from about 47 wt.% to about 91.5 wt.% of a polycarbonate polymer component; (ii) from about 5 wt.% to about 50 wt. % of a reinforcing filler; (iii) from about 3 wt.% to about 7 wt.% of a flame retardant; wherein the combined wt.% value of all the components do not exceed about 100 wt.%; and wherein all weight percent values are based on the total weight of the composition. The polycarbonate polymer is a polysiloxane-polycarbonate copolymer.

[0006] US 2007 / 0149661 discloses a composition comprising a polycarbonate composition; a fibrous reinforcing composition comprising glass fibers or a combination of glass fibers and carbon fibers; and a flame retardant composition comprising a phosphorus based flame retardant; and a synergist composition; wherein the composition has a flame retardancy of V-1 or better for a sample having a thickness of up to about 1.6 mm as measured in a UL-94 test and a heat distortion temperature of greater than or equal to about 75° C. when subjected to a deforming force of about 1.8 MPa. The flame retardant composition contains encapsulated polytetrafluoroethylene (PTFE).

[0007] There is a trend in the industry, to move away from the use of such per-fluoroalkyl or polyfluoroalkyl materials, typically referred to as PFAS. Accordingly, it is an object of the invention to provide for a composition that does not contain per-fluoroalkyl or polyfluoroalkyl substances, that has a desirable combination of good flow, impact, thermal stability and flame retardancy, in particular at a low thickness.

[0008] This object is met, at least in part, in accordance with the present invention, which is directed at a thermoplastic composition comprising, based on the weight of the composition,25POLYOOQ4-WO-ORD 2

[0009] (A) from 65 to 85 wt.% of polycarbonate,

[0010] (B) from 4 to 7 wt.% of flame retardant comprising phosphazene,

[0011] (C) from 5 to 25 wt.% of glass fibers,

[0012] (D) from 0.5 to 2 wt.% of polysiloxane, and

[0013] (E) from 0 to 2 wt.% of other components,

[0014] wherein

[0015] - the sum of the components (A) to (E) is 100 wt.%,

[0016] - the composition does not comprise per-fluoroalkyl or polyfluoroalkyl substances, and - the composition has or is selected to have a UL94 flame retardancy rating of V0 measured on an injection molded sample having a thickness of 1.0 mm.

[0017] Polycarbonate

[0018] The polycarbonate in the thermoplastic composition of the present invention is typically an aromatic polycarbonate, more in particular a polycarbonate comprising or consisting of repeating units originating from a bisphenol, such as in particular bisphenol A.

[0019] The polycarbonate in the thermoplastic composition of the invention can be one type of polycarbonate or a mixture of at least two polycarbonates that may be a homopolymer or a copolymer. It is preferred that the polycarbonate comprises or consists of at least one polycarbonate homopolymer obtained by reacting a bisphenol, such as bisphenol A, with a carbonate source such as phosgene or a diarylcarbonate such as diphenyl carbonate.

[0020] Accordingly, the polycarbonate of the thermoplastic composition according to the invention may be prepared using the so called interfacial process, wherein bisphenol A reacts with phosgene, or may be prepared by means of the so-called melt or direct transesterification process, wherein bisphenol A reacts with diphenyl carbonate. These two types of polycarbonate are known to the skilled person and may be further referred to herein as interfacial polycarbonate and melt polycarbonate. The skilled person knows that these two types of polycarbonates differ in amount of Fries branching, which only exists in melt polycarbonate and further in the terminal hydroxyl content, which is typically absent or at least significantly lower for interfacial polycarbonate. The Fries branching content for melt polycarbonate may be from 500 - 4000 ppm, such as from 750 - 2000 ppm.25POLYOOQ4-WO-ORD 3

[0021] It is preferred that the polycarbonate comprises or consists of interfacial polycarbonate for the reason that interfacial polycarbonate, compared to melt polycarbonate typically has a low number of hydroxyl chain ends, if any. A low amount of hydroxyl chain ends may be advantageous for heat stability and color retention of the polycarbonate.

[0022] Nonetheless, in some preferred embodiments of the present invention, the polycarbonate comprises or consists of melt polycarbonate, i.e. polycarbonate obtained by a melt transesterification process. In some embodiments the polycarbonate comprises or consists of a mixture of at least one melt polycarbonate and at least one interfacial polycarbonate. In such an embodiment the amount of melt polycarbonate may be from 30 - 70 wt.% and the amount of interfacial polycarbonate from 70 - 30 wt.%, based on the combined weight of the melt polycarbonate and the interfacial polycarbonate.

[0023] The polycarbonate may comprise or consist of interfacial polycarbonate. It is preferred that the interfacial polycarbonate is prepared by reacting bisphenol A and phosgene.

[0024] It is preferred that the polycarbonate comprises or consists of, preferably consists of, bisphenol A polycarbonate or a bisphenol A polycarbonate homopolymer.

[0025] Preferably, the polycarbonate (A) comprises, based on the weight of the polycarbonate, at least 90 wt.%, preferably at least 95 wt.%, more preferably at least 99 wt.%, of bisphenol A polycarbonate homopolymer.

[0026] Preferably, the polycarbonate (A) has a melt volume rate according to ISO 1133 at 300 °C and 1.2 kg load of from 2 to 40 cc / 10min, preferably 2 to 30 cc / 10min, preferably 2.5 to 25 cc / 10min, preferably from 2.5 to 20 cc / 10min, more preferably from 3.0 to 15 cc / 10min.

[0027] For the avoidance of doubt, the melt flow rate is the melt volume rate on the polycarbonate (A) which may be a mixture of at least two polycarbonates. The individual polycarbonates may have a melt volume rate less than 2 or more than 40 cc / 10min as long as the resulting mixture falls within the preferred range.25POLYOOQ4-WO-ORD 4

[0028] The polycarbonate (A) is a linear polycarbonate and / or a branched polycarbonate and is a bisphenol A polycarbonate.

[0029] For the purpose of flexibility in optimising the flow properties of the thermoplastic composition, it is preferred that the polycarbonate comprises, in addition to the optional branched polycarbonate, at least a first polycarbonate and a second polycarbonate, said second polycarbonate having a melt volume rate that is at least 6 cc / 10min higher than the melt volume rate of the first polycarbonate, determined in accordance with ISO 1133 (300°C, 1.2 kg). The first polycarbonate has a melt volume rate of from 2 - 16 cc / 10min and the second polycarbonate has a melt volume rate of from 12 - 40 cc / 10min, determined in accordance with ISO 1133 (300°C, 1.2 kg).

[0030] For the purpose of the present invention, a polycarbonate-polysiloxane copolymer is not regarded as a polycarbonate that may be comprised in polycarbonate (A).

[0031] The amount of polycarbonate (A) in the composition is from 65 to 85 wt.%, preferably 65 to 80 wt.%, preferably 65 to 75 wt.%.

[0032] The polycarbonate (A) preferably comprises branched polycarbonate. Branched polycarbonate is known per se and is typically an interfacial polycarbonate. For the purpose of the present invention melt polycarbonate having a certain amount of Fries branching is not to be considered as branched polycarbonate.

[0033] Preferably the amount of branched polycarbonate is from 5 to 60 wt.%, preferably 20 to 50 wt.% based on the weight of the polycarbonate (A). More preferably the amount of branched polycarbonate is from 25-40 wt.%. The branched polycarbonate is preferably a bisphenol A polycarbonate homopolymer. The branching units may correspond to known branching agents as used in the process to manufacture branched polycarbonate.

[0034] Branched polycarbonates, known per se, can be manufactured by adding a branching agent during the (interfacial) polymerisation process. The branching agent is added in an amount (relative to the bisphenol monomer) that is sufficient to achieve the desired branching content. Branching agents include aromatic triacyl halides, for example triacyl chlorides of formula (1)25POLYOOQ4-WO-ORD 5

[0035] (1)

[0036]

[0037] wherein Z is a halogen, C1.3 alkyl, C1-3 alkoxy, C7-12 arylalkylene, C7-12 alkylarylene, and z is 0 to 3;

[0038] a trisubstituted phenol of formula (2)

[0039] (2)

[0040]

[0041] OH

[0042] wherein T is a C1.20 alkyl, C1-20 alkyleneoxy, C7-12 arylalkyl, or C7-12 alkylaryl, Y is a halogen, C1-3 alkyl, C1-3 alkoxy, C7-12 arylalkyl, C7-12 alkylaryl and y is 0 to 4;

[0043] or a compound of formula (3) (isatin-bis-phenol).

[0044]

[0045] H25POLYOOQ4-WO-ORD 6

[0046] Examples of specific branching agents that are particularly effective include trimellitic trichloride (TMTC), tris-p-hydroxyphenylethane (THPE), and isatin-bis-phenol, with THPE being the preferred one.

[0047] The desired degree of branching can be achieved by appropriately selecting the reaction conditions, the amount of branching agents and the amount of chain stopper (i.e. endcapping agent) as applied in the interfacial process. This is known to the skilled person per se.

[0048] In general, the amount of branching agent is effective to provide 0.1 to 10 branching units per 100 of repeating bisphenol units of the polycarbonate, specifically 0.5 to 8 branching units per 100 bisphenol units, and more specifically 0.75 to 5 branching units per 100 bisphenol units.

[0049] A combination of two or more branching agents may be used.

[0050] The branched polycarbonate may have a melt volume rate of from 0.2 to 5, preferably 0.5 to 3, more preferably 0.8 to 2 cc / 10 min as determined in accordance with ISO 1133 (300°C, 1.2 kg). Preferably the branched polycarbonate is a bisphenol A polycarbonate homopolymer with branching units derived from THPE.

[0051] For branching agents having formula (2) or (3), the branching agent triphenyl carbonate groups formed are present in an amount of 0.1 to 10 branching units per 100 R1 units, specifically 0.5 to 8 branching units per 100 R1 units, and more specifically 0.75 to 5 triphenylcarbonate units per 100 R1 units. In some embodiments, a combination of two or more branching agents may be used. Alternatively, the branching agents can be added at a level of 0.05 to 2.0 wt.%.

[0052] In some embodiments, the polycarbonate comprises post-consumer recycled (PCR) polycarbonate or post-industrial recycled (PIR) polycarbonate. Thus, the polycarbonate (A) may comprise recycled polycarbonate, preferably mechanically recycled or solvent-recycled polycarbonate. Preferably the amount of recycled polycarbonate is from 10 to 90 wt.%, preferably 10 to 40 wt.%, more preferably 10 to 30 wt.%, based on the weight of the polycarbonate (A).25POLYOOQ4-WO-ORD 7

[0053] Flame Retardant

[0054] The flame retardant of the invention comprises or consists of phosphazene. The flame retardant preferably comprises at least 50 wt.%, more preferably at least 75 wt.%, more preferably at least 90 wt.%, more preferably at least 95 wt.% and most preferably at least 99 wt.% of phosphazene based on the weight of the flame retardant.

[0055] The amount of flame retardant is from 4 to 7 wt.%, based on the weight of thermoplastic composition. Preferably the amount of flame retardant is from 4 to 6.5 wt.%, more preferably from 4 to 6 wt.%, most preferably from 4 to 5.5 wt.%.

[0056] The present invention is not strictly limited to any particular kind of phosphazene compound. Phosphazene compounds are commercially available and known to the skilled person per se.

[0057] It is however an important aspect of the present invention that the amount of phosphazene flame retardant (also referred to as phosphazene) in the thermoplastic composition is kept as low as possible in order not to affect other properties of the thermoplastic composition such as in particular, the heat resistance in terms of heat deflection temperature and / or Vicat softening temperature, or mechanical properties.

[0058] The phosphazene may be a halogenated phosphazene compound, having the following structure:

[0059]

[0060] 25POLYOOQ4-WO-ORD 8

[0061] where R8, R10 and R12 can be the same or different and can independently be a hydrogen, a halogen, an aryl group, an aralkyl group, a C1-12 alkoxy, a C1-12 alkyl, a C1-12 haloalkyl or a combination thereof.

[0062] An exemplary phenoxyphosphazene is a halogenated phenoxyphosphazene such as trifluorophenoxyphosphazene having the structure:

[0063]

[0064] A useful commercially available trifluorophenoxyphosphazene is F - PhZ commercially available from Cenway Tech under the brand name CWFR - TFTP.

[0065] For the avoidance of doubt and for the purpose of the present invention the structures above, where the fluoro atom is bonded to a phosphorus atom is not considered as PF AS.

[0066] The phosphazene may however be free of halogen atoms.

[0067] The phosphazene is preferably a cyclic phosphazene, more preferably selected from the group consisting of propoxyphosphazene, phenoxyphosphazene, methylphenoxyphosphazene, aminophosphazene and fluoroalkylphosphazenes. The phosphazenes preferably has the structure of formula 6 below:25POLYOOQ4-WO-ORD 9

[0068] (6)

[0069]

[0070] wherein Ri to R6can be the same or different and can be

[0071] an aryl group,

[0072] an optionally substituted aralkyl group,

[0073] - a C1-12 alkyl group, preferably methyl, ethyl, propyl or butyl,

[0074] C5- to C6-cycloalkyl which is in each case optionally substituted by alkyl, preferably C1-4 alkyl,

[0075] a hydrogen

[0076] and k is an integer from 1 to 10, preferably from 1 to 8, more particular preferable from 1 to 5.

[0077] Preferably the cyclic phosphazene has a proportion of oligomers having k=1 (trimer) from 50 to 98 mol % preferably from 70 to 90 mol % and more preferably 70-85 mol %. More preferably, the phosphazene is phenoxyphosphazene having the structure of formula 6 below (all radicals R1 - R6are a phenyl group), having a proportion of oligomers having k=1 of at least 50 mol%, preferably at least 80 mol%, more preferably at least 98 mol%, or within a range of from 50 - 98 mol%.25PCLY0004-WO-ORD 10

[0078]

[0079] In a preferred aspect, the proportion of tetramers (k=2) is from 2 to 50 mol %, based on the amount of cyclic phosphazene, preferably from 5 to 40 mol %.

[0080] In another aspect, the proportion of the higher oligomeric phosphazenes (k=3 -10 or 3-8 or 3-5, depending on the selection for k) is from 0 to 30 mol %, preferably from 2 to 25 mol % based on the amount of cyclic phosphazene.

[0081] The proportion of oligomers having k > 8 is from 0 to 2 mol %, based on the amount of cyclic phosphazene, preferably from 0.1 to 1 mol %.

[0082] Most preferably, the cyclic phosphazene substantially consists or consists of phenoxyphosphazene wherein k is at most 8 and having a proportion of trimer (k=1) of from 70 to 85 mol %, a proportion of tetramer (k=2) of from 10 to 20 mol %, a proportion of higher oligomeric phosphazenes (k=3, 4, 5, 6 and 7) of from 5 to 15 mol %, wherein the total of cyclic phosphazenes wherein k is at most 8 is 100 mol%. In this respect the term “substantially consists” means that an amount of cyclic phosphazenes wherein k is more than 8 is at most 2 mol %.

[0083] R1 to R6 in formula (7) above may comprise one or more halogen atoms.

[0084] Commercially available phenoxy-phosphazenes include Rabitle FP110 and Rabitle FP 110-T manufactured by FUSHIMI Pharmaceutical Co., Ltd. Rabitle FP110 is free of halogen and antimony.25PGLY0004-WO-ORD 11

[0085] It is however preferred that the phosphazene does not contain any halogen substituents. In particular, the phosphazene is preferably free of fluoro substituents.

[0086] The flame retardant may comprise further flame retardants in addition to the phosphazene, where it is noted that polycarbonate-polysiloxane copolymers are not considered as flame retardant with regards to component (B) of the thermoplastic composition. Any further flame retardant does not comprise per-fluoroalkyl or polyfluoroalkyl substances (PFAS) and preferably does not contain any halogens, in particular fluorine or bromine.

[0087] The flame retardant preferably does not contain a flame retardant salt.

[0088] The flame retardant, and accordingly the thermoplastic composition preferably do not comprise a sulphone or a sulphone sulphonate, such as salts of a sulphone or sulphone sulphonate. It is preferred that other than phosphazene the thermoplastic composition does not comprise any other flame retardants. Thus, it is preferred that the flame retardant consists of phosphazene.

[0089] Glass fibers

[0090] The composition according to the invention comprises glass fibers. The amount of the glass fibers in the composition is 5 to 25 wt.%, such as from 5 to 24 wt.%, preferably 5 to 22 wt.%, more preferably 5 to 21 wt.%, more preferably 5 to 20 wt.%, with respect to the total composition.

[0091] It is found by the present inventors that using up to 25 wt.% of glass fibers in composition allows in maintaining impact properties of articles manufactured from the composition according to the invention, making the composition according to the invention particularly suitable for use in the manufacture of electrical & electronic articles, such as for large enclosures.

[0092] The glass fibers may comprise non-bonding glass fibers and / or bonding glass fibers. Preferably, the glass fibers comprise non-bonding glass fibers. This was found to result in a better flame retardance and impact of the composition according to the invention.25PCLY0004-WO-ORD 12

[0093] Preferably, the amount of the non-bonding glass fibers in the composition according to the invention is 30 to 50 wt%, more preferably 35 to 45 wt%, with respect to the total composition.

[0094] Preferably, the amount of the non-bonding glass fibers with respect to the total amount of glass fibers is at least 50 wt%, at least 75 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt% or 100 wt%.

[0095] In other embodiments, the amount of the bonding glass fibers with respect to the total glass fibers is at least 50 wt%, at least 75 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt% or 100 wt%.

[0096] A non-bonding glass fiber, also characterized as a non-binding glass fiber, may refer to a glass fiber filler that does not provide specific adhesion to a polymer resin to which it is added. That is, individual fibers of the glass fiber filler may not demonstrate an affinity towards the polymer matrix. Comparatively, bonding glass fiber provides specific adhesion with the specific polymer resin to which it is added. A bonding 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.

[0097] In one aspect, the disclosed compositions comprise a non-bonding glass fiber selected from E-glass, S-glass, AR-glass, T-glass, D-glass and R-glass. In a still further aspect, the non-bonding glass fiber may be selected from E-glass, S-glass, and combinations thereof. In one example, the non-bonding glass fiber is an E-glass or EC glass type.

[0098] The non-bonding 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.

[0099] In a further aspect, the non-bonding glass fiber may be a long fiber or a chopped fiber. Preferably the glass fiber is a chopped fiber. Glass fibers in the form of chopped strands may have a length of about 0.3 millimeter to about 10 centimeters, specifically about 0.5 millimeter to about 5 centimeters, and more specifically about 1.0 millimeter to about 2.5 centimeters. In various further aspects, the glass fiber has a length from about 0.2 mm25POLYOOQ4-WO-ORD 13

[0100] to about 20 mm. In a yet further aspect, the glass fiber has a length from about 0.2 mm to about 10 mm. In an even further aspect, the glass fiber has a length from about 0.7 mm to about 7 mm. In a still further aspect, the glass fiber can have a length of 1 mm or longer. In yet a further aspect, the glass fiber can have a length of 2 mm or longer.

[0101] Polysiloxane

[0102] The thermoplastic composition comprises from 0.5 to 2 wt.%, preferably 0.5 to 1.5 wt.%, more preferably 0.5 to 1 wt.%, based on the weight of the thermoplastic composition of polysiloxane compound.

[0103] The polysiloxane may be a single polysiloxane or a mixture, in which case the amount cited above is the combined amount of all polysiloxanes.

[0104] Polysiloxanes are known to the skilled person per se and typically contain siloxane (O-Si-O) repeating units in a backbone. The silicon atom is typically bonded with organic group such as C1-C10 branched or linear alkyl groups, aryl groups or arylalkyl groups. The silicon atom may also be bonded to a hydrogen group. Alternatively or in addition, the silicon atom may contain alkoxy or phenoxy groups. If a polysiloxane contains at least one organic group, then the polysiloxane may also be referred to as a polyorganosiloxane.

[0105] A polysiloxane contains a plurality of Si — O — Si bonds which form a polymer chain, wherein the backbone of the polymer chain consists of — (Si — O) — repeating units.

[0106] A polysiloxane or polyorganosiloxane contains repeating (Si — O) units where at least one Si atom carries at least one organic group, i.e. group containing at least one carbon atom.

[0107] A polysiloxane comprises end groups and side groups. An end group is a chemical group attached to a Si atom located at one end of the polymer chain. A side group is a group attached to a Si atom, wherein the Si atom is not located at the end of the chain. A polyorganosiloxane, sometimes referred to as organopolysiloxane, typically contains a mixture of the following structures:25POLYOOQ4-WO-ORD 14

[0108] (8)

[0109] R

[0110] vw-O — Si — O-zvvi (9)

[0111] I

[0112] R

[0113] (10)

[0114] (11)

[0115]

[0116] wherein 8, 9, 10 and 11 represent the functionality of structural groups of organopolysiloxane. In particular, 8 represents a monofunctional group R3SiOi / 2; 9 represents a difunctional group R2SiO2 / 2; 10 represents a trifunctional group RSiO3 / 2; and 11 represents a tetrafunctional group SiO4 / 2. Thus, for example linear organopolysiloxanes have a backbone of 9 units and the end groups are 8 units while branched organopolysiloxanes have, depending on the amount of branching, a number of 10 and / or 11 units.

[0117] The groups R in the structures above may be the same or different and are typically hydrogen, C1- C10 alkyl, C1-C10 alkoxy, aryl, aryl, aryalkyl, alkyaryl, either substituted or linear. Typically, and preferably the groups R are selected from methyl, methoxy, phenyl, phenoxy and hydrogen. For example, the polysiloxane in accordance with the present invention may comprise F units wherein each R is a methyl group, or wherein the R groups are methyl and phenyl groups.25POLYOOQ4-WO-ORD 15

[0118] It is preferred that the polysiloxane comprises at least 85 mol% of F units and wherein R in the F units is the same or different and selected from methyl and phenyl. It is preferred that the backbone of the polysiloxane comprises or consists of dimethyl-siloxane repeating units, methyl-phenyl siloxane repeating units, phenyl-phenyl-siloxane repeating units or combinations of these repeating units, which may be present in the polysiloxane in a random configuration. Preferably the polysiloxane comprises or consists of poly-dimethyl siloxane.

[0119] It is preferred that the polysiloxane has a kinematic viscosity of at least 90 cSt, preferably 100 - 140 cSt, most preferably 110 - 140 cSt (at 25 °C).

[0120] For the avoidance of doubt and within the context of the present invention, any solid material like e.g. glass fibers or fillers such as talc and which contain a polysiloxane sizing or coating are not considered as polysiloxanes.

[0121] Other components

[0122] The thermoplastic composition may comprise further components including, but not strictly limited to anti-oxidants, thermal stabilizers, mold release agents, UV stabilizers, anti-static agents, pigments and / or dyes. Preferably, the amount of further components (E) is at most 2, preferably 0.5 to 2 wt.%, more preferably at most 1.5 or 1 wt.%. In an embodiment the thermoplastic composition comprises at least one type of further component (E).

[0123] The thermoplastic composition of the present invention preferably comprises carbon black, titanium dioxide, a dye and combinations of the foregoing.

[0124] Thermoplastic Composition

[0125] The composition of the present invention preferably has as a melt volume rate of at least 3 cc / 10min, preferably from 3.5-20 cc / 10 min, preferably from 3.5- 10 cc / 10 min, more preferably 4 - 9 cc / 10 min, more preferably 4.5 - 7.5 cc / 10 min, determined in accordance with ISO 1133 (300°C, 1.2kg).

[0126] The composition of the invention does not comprise per-fluoroalkyl or polyfluoroalkyl substances. The composition does not contain poly-tetrafluoroethylene.25POLYOOQ4-WO-ORD 16

[0127] Preferably the composition of the invention does not comprise polycarbonatepolysiloxane copolymers.

[0128] The composition of the present invention has good flame retardance property. Preferably, the composition preferably has or is selected to have a UL94 flame retardancy rating of VO measured on an injection molded sample having a thickness of 1.0 mm. Preferably, the composition preferably has or is selected to have a UL94 flame retardancy rating of VO measured on an injection molded sample having a thickness of 0.8 mm. Preferably, the composition passes or is selected to pass the UL945VB flame retardancy test measured on an injection molded sample having a thickness of 3.0 mm.

[0129] Preferably, the composition has or is selected to have a heat distortion temperature (HDT) determined in accordance with ISO 75 / Af (1.8 MPa), measured on an injection molded sample with a thickness of 4 mm of at least 118°C, preferably at least 120 °C, even more preferably at least 122 °C.

[0130] Preferably, the composition has or is selected to have, an unnotched Izod impact strength determined in accordance with ISO 179, measured on an injection molded sample with a thickness of 4 mm, at a temperature of 23°C of at least 18 kJ / m2, preferably at least 20 kJ / m2.

[0131] Article

[0132] An article comprising or consisting of the thermoplastic composition as disclosed herein can be manufactured using any known technique such as extrusion molding, injection molding, blow molding, thermoforming etc.

[0133] The thermoplastic composition in accordance with the invention is particularly suited for the manufacture of articles that are comprised in or consists of the housing of electrical or electronic parts, preferably consumer electronic devices, charging equipment for electrical vehicles or smart meters. For example, the thermoplastic composition of the invention may be used for the manufacture of parts of mobile phones, tablets, chargers for mobile phones or tablets, televisions, computer monitors, laptop computers, desktop computers, printers, scanners, pro audio equipment like mixing desks, guitar modelers,25PCLY0004-WO-ORD 17

[0134] subwoofer, and the like. Alternatively, the thermoplastic composition may be used for the manufacture of articles comprised in or constituting interior automotive applications.

[0135] The present invention will now be further elucidated on the basis of the following non-limiting examples.

[0136] Table 1: Raw materials

[0137] PC1 Bisphenol A polycarbonate homopolymer manufactured with an interfacial process and having a melt volume rate of 6 cc / 10 min in accordance with ISO 1133 (300°C, 1.2 kg). It has a weight average molecular weight of 60,000 g / mol available from SABIC (PC 105).

[0138] PC2 Bisphenol A polycarbonate homopolymer manufactured with an interfacial process and having a melt volume rate of 13 cc / 10 min in accordance with ISO 1133 (300°C, 1.2 kg). It has a weight average molecular weight of 39,000 g / mol available from SABIC (PC 175).

[0139] PC3 Branched bisphenol A polycarbonate homopolymer manufactured with an interfacial process and having a melt volume rate of 2 cc / 10 min. It has a weight average molecular weight of 36,000 g / mol available from SABIC (ML 6739). Glass Fiber 10micron diameter Non-bonded glass fiber from NEG (Nippon Electric Glass).

[0140] Phosphazene (PPZ) Phenoxyphosphazene (hexaphenoxycyclotriphosphazene) commercially available as Rabitle FP-110T from Fushimi. Siloxane (DMS C16) Hydroxy terminated Polydimethyl siloxane with viscosity 50 to 65cSt with CAS No. 104780-66-7 available from Gelest.

[0141] Siloxane (DMS C21) Hydroxy terminated Polydimethyl siloxane with viscosity 110 to 140 cSt with CAS No. 156327-07-0 available from Gelest. PETS (Mold Release Pentaerythritol tetrastearate with CAS 115-83-3 available from Agent) BASF.

[0142]

[0143] 25POLYOOQ4-WO-ORD 18

[0144] A0168 Tris(2,4-di-t-butylphenyl)phosphite, commercially available from BASF as Irgafos 168.

[0145] Tinuvin 360 UV light absorber, CAS No 103597-45-1 from BASF.

[0146]

[0147] Table 2

[0148] Melt volume rate was determined in accordance with ISO 1133 at MVR 300°C under a load of 1 ,2kg.

[0149] Heat deflection temperature (HDT) in °C was determined in accordance with ISO 75 / Af at a load of 1.8 Mpa on injection molded HDT

[0150] test samples with a thickness of 4 mm. Flat-wise 80x10x4 mm, span length =64 mm, un-annealed.

[0151] Un-Notched Izod Impact, in kJ / m2, was tested on injection molded samples in accordance with ISO 179.

[0152] UNII

[0153] The standard specimen is 80 x 10 x 4 mm. A 11 J hammer is used. Measurements were carried out at room temperature (23 ± 2 °C).

[0154] Flame retardancy was measured according to the UL94 test standard at a sample thickness of 1.2 mm, 1.0 mm, and 0.8 mm.

[0155] The test bars were burnt at the gated end for Vx evaluation.

[0156] Prior to testing part of the samples were conditioned at 23 °C and 50% relative humidity for 48 hours and another part at 70 °C and 50 % Flame

[0157] relative humidity for 168 hours.

[0158] retard a ncy

[0159] Both conditioned samples were tested. The lowest flame retardancy is reported.

[0160] Flame retardancy was measured according to the UL94 5VB test standard at a sample thickness of 3.0mm.

[0161]

[0162] 25POLYOOQ4-WO-ORD 19

[0163] Table 3

[0164] Parameters Unit

[0165] Compounder Type NONE ZSK-25

[0166] Barrel Size Mm 1025

[0167] Die Mm 2 X 2

[0168] Zone 1 (Feeding) Temp °C 40

[0169] Zone 2 Temp °C 170

[0170] Zone 3 Temp °C 220

[0171] Zone 4 Temp °C 240

[0172] Zone 5 Temp °C 255

[0173] Zone 6 Temp °C 255

[0174] Zone 7 Temp °C 270

[0175] Zone 8 Temp °C 280

[0176] Zone 9 Temp °C 280

[0177] Zone 10 Temp °C 280

[0178] Die Temp °C 280

[0179] Screw speed Rpm 300

[0180] Throughput kg / hr 9 ~ 10

[0181] Torque % 60~ 65

[0182] Vacuum 1 MPa -0.08

[0183] Side Feeder position 6th Zone

[0184]

[0185] Compositions of Tables 4 and 5 made by dry blending the ingredients of Table 1 except for the glass fibers and adding the blends at the throat feeder in a 25 mm diameter Twin Screw Extruder (TSE) ZSK-25 having side screw feeding capability. Glass fibers were fed through side feeder at 6thzone as shown in Table 3. Various properties as shown in Table 2 were measured on injection molded specimens according to the mentioned methods.25POLYOOQ4-WO-ORD 20

[0186] Table 4

[0187] Components /

[0188] Properties Units C1 C2 E1 E2 E3 E4 E5 PC1 wt.% 52.95 56.16 52.25 52.25 49.65 43.75 42.95 PC2 wt.% 22.7 18.49 22.4 22.4 10.9 10.7 PC3 wt.% 25 20 20 PPZ wt.% 4 5 4 4 5 4 5 DMS C16 wt.% 1

[0189] DMS C21 wt.% 1 1 1 PETS wt.% 0.3 0.3 0.3 0.3 0.3 0.3 0.3 A0168 wt.% 0.05 0.05 0.05 0.05 0.05 0.05 0.05 Glass Fiber wt.% 20 20 20 20 20 20 20

[0190] Total wt.% 100 100 100 100 100 100 100

[0191] MVR co / 10min 6.2 7.1 6.7 6.7 4.6 5.1 4.9 HDT °C 126.4 123.6 125.7 126.4 125.3 127.8 122.9 UNII kJ / m222.6 21.4 45.4 59.8 25 33.3 62.7 UL94 @ 1.2 V-0 / V-1 V-1 V-0 / V-0

[0192] mm V-0 / V-1

[0193] UL94 @ 1.0 V-0 V-0 V-0 V-0 mm

[0194] UL94 @ 0.8

[0195] mm V-2 V-0 V-2 V-0 UL945VB @

[0196] 3.0 mm Pass Pass Pass Pass Pass

[0197]

[0198] The compositions according to the invention, E2-E5 achieve UL94 VO rating at 1.0mm thickness as compared to C1-C2 (Table 4).

[0199] The composition in accordance with the invention, E1-E5 have higher Un-Notched Izod Impact compared to Comparative Examples C1-C2. Further, the composition in accordance with the invention, E3 and E5 achieves a UL94 VO rating at 0.8mm thickness with a higher Un-Notched Izod Impact compared to Comparative Examples C1-C2 while maintaining HDT.25PCLY0004-WO-ORD 21

[0200] It was observed that with 10 % Glass Fiber filled PC composition, PPZ alone did not show FR performance at 1.0mm thickness as evident by Comparative Example C3 in Table 5. However by using the composition in accordance with the invention, E6 and E7 achieves a UL94 VO rating at 1.0mm thickness and higher Un-Notched Izod Impact as compared to Comparative Example C3 while maintaining HDT.

[0201] The material composition of present invention passes the UL 94 5VB test with 3 mm thickness.

[0202] Table 5

[0203] Components /

[0204] Properties Units C3 E6 E7

[0205] PC1 wt.% 59.5 53.55 52.65

[0206] PC2 wt.% 5.95 5.85

[0207] PC3 wt.% 25 25 25

[0208] PPZ wt.% 5 4 5

[0209] DMS C21 wt.% 1 1

[0210] PETS wt.% 0.3 0.3 0.3

[0211] A0168 wt.% 0.05 0.05 0.05

[0212] Tinuvin 360 wt.% 0.15 0.15 0.15

[0213] Glass Fiber wt.% 10 10 10

[0214] Total wt.% 100 100 100

[0215] MVR co / 10min 5.5 5.7 5.4

[0216] HDT °C 121.2 123.1 121.7

[0217] UNII kJ / m2113.7 174.7 187.8

[0218] UL94 @ 1.0 V-1 V-0 V-0

[0219] UL94 @ 0.8 V-1 V-0

[0220] UL945VB @ 3.0 Pass Pass Pass

[0221]

Claims

25POLYOOQ4-WO-ORD 22C LA I M S1. A thermoplastic composition comprising, based on the weight of the composition, (A) from 65 to 85 wt.% of polycarbonate;(B) from 4 to 7 wt.% of flame retardant comprising phosphazene;(C) from 5 to 25 wt.% of glass fibers;(D) from 0.5 to 2 wt.% of polysiloxane; and(E) from 0 to 2 wt.% of other components,wherein- the sum of the components (A) to (E) is 100 wt.%,- the composition does not comprise a per-fluoroalkyl or a polyfluoroalkyl substances, and- the composition has or is selected to have a UL94 flame retardancy rating of VO measured on an injection molded sample having a thickness of 1.0 mm.

2. The thermoplastic composition of claim 1 , wherein the composition has or is selected to have a melt volume rate determined in accordance with ISO 1133 (300 °C, 1.2 kg) of at least 3 cc / 10min, preferably from 3.5 - 10 cc / 10min, more preferably from 4- 9 cc / 10 min, more preferably from 4.5 - 7.5 cc / 10 min.

3. The thermoplastic composition of any one or more of claims 1 - 2, wherein the flame retardant comprises at least 90 wt.%, preferably at least 95 wt.% more preferably at least 99 wt.% of phosphazene, based on the weight of the flame retardant.

4. The thermoplastic composition of any one or more of claims 1 - 3, wherein the phosphazene has a structure represented by the formula (I), wherein Ri to R6can be the same or different and can be an aryl group, an aralkyl group, a C1-12 alkyl, or a combination thereof and k is an integer from 1 to 10, preferably from 1 to 8.25POLYOOQ4-WO-ORD 23R6R5 (I)5. The thermoplastic composition of any one or more of claims 1 - 4, wherein the glass fibers (C) comprise at least 90 wt.%, based on the weight of the glass fibers, of a non-bonding glass fibers.

6. The thermoplastic composition of any one or more of claims 1 - 5, wherein the polycarbonate comprises a linear and / or a branched bisphenol A polycarbonate homopolymer.

7. The thermoplastic composition of any one or more of claims 1 - 6, wherein the polycarbonate comprises, optionally in addition to branched polycarbonate, at least a first polycarbonate and a second polycarbonate, said second polycarbonate having a melt volume rate that is at least 6 cc / 10min higher than the melt volume rate of the first polycarbonate, determined in accordance with ISO 1133 (300 °C, 1.2 kg).

8. The thermoplastic composition of any one or more of claims 1 - 7, wherein the composition has or is selected to have a UL94 flame retardancy rating of VO measured on an injection molded sample having a thickness of 0.8 mm.

9. The thermoplastic composition of any one or more of claims 1 - 8, wherein the composition passes or is selected to pass the UL94 5VB flame retardancy test measured on an injection molded sample having a thickness of 3.0 mm.

10. The thermoplastic composition of any one or more of claims 1 - 9, wherein the polysiloxane has a kinematic viscosity of at least 90 cSt (at 25 °C).25POLYOOQ4-WO-ORD 2411. The thermoplastic composition of any one or more of claims 1 - 10, wherein the composition has or is selected to have a heat distortion temperature (HDT) determined in accordance with ISO 75 / Af (1.8 MPa), measured on an injection molded sample with a thickness of 4 mm of at least 118°C, preferably at least 120 °C, even more preferably at least 122 °C.

12. The thermoplastic composition of any one or more of claims 1-11, wherein the composition has or is selected to have, an unnotched Izod impact strength determined in accordance with ISO 179, measured on an injection molded sample with a thickness of 4 mm, at a temperature of 23°C of at least 18 kJ / m2, preferably at least 20 kJ / m2.

13. The thermoplastic composition of any one or more of claims 1 - 12, wherein the polycarbonate comprises or consists of polycarbonate obtained by an interfacial process.

14. An article comprising or consisting of the thermoplastic composition of any one or more of claims 1 - 13.

15. The article of claim 14, wherein said article consists of or is comprised in an electrical or electronic device.

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