Water stable thermoplastic composition

Abstract

The invention relates to a thermoplastic composition comprising, based on the weight of the composition, (A) 40 to 70% by weight of an aromatic polycarbonate, (B) 20 to 40% by weight of a polyester, (C) 0.1 to 10% by weight of a hydrolysis stabilizer composition comprising at least one compound containing epoxy functions, (D) 0 to 15% by weight of an impact modifier, (E) 0 to 5% by weight of further components, wherein the total amount of (A) to (E) is 100% by weight, and wherein the composition is selected to have a combination of at least 50 kJ / m2 of an initial Notched Izod Impact, determined according to ISO 180-1A at a temperature of 23 DEG C, at least 70% of a Notched Izod Impact Retention, determined according to the method described in the specification, a heat distortion temperature of at least 90 DEG C as determined according to ISO 75A lay-flat mode under a load of 1.8 MPa.

Description

[0001] The present invention relates to a water-stable thermoplastic composition comprising a polycarbonate and a polyester. The present invention further relates to an article comprising or consisting of such a composition.

[0002] Compositions comprising polycarbonate and polyester have excellent appearance, mechanical properties, dimensional stability and chemical resistance, and are widely used in various fields. In particular, compositions consisting of polycarbonate and poly(butylene terephthalate) (PBT) impart excellent mechanical properties (e.g., impact, ductility and dimensional stability) and chemical resistance to polycarbonate. These compositions are particularly useful in the field of interior and exterior parts such as in automobiles.

[0003] However, polyesters such as PBT having a relatively large number of -COOH end groups can affect the stability of polycarbonates in polyester-polycarbonate blends. It is believed that the -COOH end groups of the polyester can cause the polycarbonate to lose molecular weight, resulting in changes in the properties of the polycarbonate. This effect can be enhanced by the presence of catalysts or catalyst residues that may be applied during the manufacture of the polycarbonate.

[0004] US 9,920,198 discloses blends of polycarbonate (PC) and polylactic acid (PLA) comprising (a) branched bisphenol APC, (b) PLA, (c) a chain extender, and (d) a glycidyl methacrylate (GMA) functionalized polyolefin copolymer / terpolymer.

[0005] US 7,923,506 discloses a molding composition comprising: (a) 20 to 49.9 weight percent of a first polyester component having an intrinsic viscosity of 0.5 to 1.0 and comprising a first polybutylene terephthalate random copolymer which (1) is derived from a polyethylene terephthalate copolymer and (2) has at least one residue derived from a polyethylene terephthalate component; and (b) 20 to 49.9 weight percent of a second polyester component having an intrinsic viscosity of 1.1 to 1.4 The invention relates to a polyester having an intrinsic viscosity of 1000 μm and comprising a second polybutylene terephthalate random copolymer which (1) is derived from a polyethylene terephthalate component selected from polyethylene terephthalate and polyethylene terephthalate copolymers and (2) has at least one residue derived from the polyethylene terephthalate component; and (c) 0.01 to 20 weight percent of a carboxyl reactive component; wherein the first polyester component, the second polyester component and the optional at least one additive are present in a total amount of 100 weight percent.

[0006] The impact properties of compositions comprising polycarbonate and polyester can be enhanced by adding suitable impact modifiers. Such impact modifiers can be prepared by means of an emulsion polymerization process including the use of processing aids such as emulsifiers and coagulants. Such processing aids, if part of the impact modifier, may also cause the decomposition of the polycarbonate, i.e. promote hydrolysis.

[0007] In addition to the above, a quencher is usually added to the composition comprising polycarbonate and polyester in order to prevent transesterification of the polyester and the polycarbonate. Such quenchers are usually moderately acidic. In order to maintain a certain level of hydrolytic stability of the composition, it is necessary to select the quencher so that its acidity is sufficient to quench the residual catalyst in the polyester, but at the same time it does not significantly cause hydrolysis of the polycarbonate.

[0008]

[0006] It would therefore be desirable to provide compositions comprising polycarbonates and polyesters which have improved hydrolytic stability in demanding applications, particularly where the compositions may be exposed to moisture at elevated temperatures.

[0009] It is an object of the present invention to provide thermoplastic compositions which have good initial mechanical properties and are suitable for use in applications in which the composition may be exposed to moisture at elevated temperatures.

[0010] Another object of the present invention is to provide a thermoplastic composition comprising polycarbonate and polyester, wherein the composition has a good combination of water stability, impact properties and thermal stability.

[0011] According to the present invention, these objects are at least partially met. The present invention relates to a thermoplastic composition comprising, based on the weight of the composition:

[0012] (A) 40 to 70% by weight of an aromatic polycarbonate,

[0013] (B) 20 to 40% by weight of polyester,

[0014] (C) 0.1 to 10% by weight of a hydrolysis stabilizer composition comprising at least one compound containing epoxy functional groups,

[0015] (D) 0 to 15 wt. % of an impact modifier,

[0016] (E) 0 to 5% by weight of other components,

[0017] wherein the total amount of (A) to (E) is 100 wt %, and wherein the composition has or is selected to have the following combination:

[0018] At least 50 kJ / m 2 Initial notched Izod impact measured at 23°C according to ISO180-1A,

[0019] A notched Izod impact retention of at least 70% as determined by the method set out in the specification,

[0020] Heat distortion temperature of at least 90°C measured in accordance with ISO 75A lay-flat method under a load of 1.8 MPa.

[0021] The present invention will now be described in more detail.

[0022] Aromatic polycarbonate

[0023] In the context of the present invention, the term polycarbonate is understood to mean aromatic polycarbonate. The terms "polycarbonate" and "aromatic polycarbonate" both therefore have the same meaning and can be used interchangeably. As known to the skilled person, aromatic polycarbonates are polycarbonates containing aromatic groups.

[0024] Aromatic polycarbonates are generally manufactured using two different technologies. In the first technology, which is called the interfacial technology or interfacial process, phosgene reacts with bisphenol, usually bisphenol A (BPA), in the liquid phase. Another well-known technology is the so-called melt technology, sometimes also called melt transesterification or melt polycondensation technology. In the melt technology or melt process, a bisphenol, usually BPA, reacts with a carbonate, usually diphenyl carbonate (DPC), in the melt phase. Aromatic polycarbonates obtained by the melt transesterification process are known to be structurally different from aromatic polycarbonates obtained by the interfacial process. In this regard, it should be particularly noted that the so-called "melt polycarbonate" usually has the least amount of Fries branches, and Fries branches are generally absent in "interfacial polycarbonates". In addition, melt polycarbonates usually have a greater number of phenolic hydroxyl end groups, while polycarbonates obtained by the interfacial process are usually end-capped and have phenolic hydroxyl end groups of up to 150 ppm, preferably up to 50 ppm, and more preferably up to 10 ppm. Usually, the amount of phenolic hydroxyl end groups is below the detection limit.

[0025] According to the present invention, it is preferred that the aromatic polycarbonate comprises bisphenol A polycarbonate or a mixture of bisphenol A polycarbonate or consists of bisphenol A polycarbonate or a mixture of bisphenol A polycarbonate, preferably wherein at least a portion of the bisphenol A polycarbonate is prepared by melt transesterification of bisphenol A and diphenyl carbonate. Preferably, the aromatic polycarbonate of the present invention disclosed herein comprises at least 75% by weight, preferably at least 95% by weight of bisphenol A polycarbonate based on the total amount of aromatic polycarbonate. More preferably, the aromatic polycarbonate in the composition consists essentially of bisphenol A polycarbonate or consists of bisphenol A polycarbonate. Preferably, the aromatic polycarbonate has a weight average molecular weight (Mw) of 15,000 to 60,000 g / mol measured using gel permeation chromatography using polystyrene standards. Preferably, the Mw of the aromatic polycarbonate is 20,000 to 45,000 g / mol. If the polycarbonate is a mixture of two or more aromatic polycarbonates, the Mw should be determined based on the mixture, wherein preferably each of the aromatic polycarbonates constituting the mixture has an Mw of 20,000 to 45,000 g / mol.

[0026] In one aspect, the aromatic polycarbonate is an interfacial polycarbonate.

[0027] In another aspect, the aromatic polycarbonate is a melt polycarbonate.

[0028] In yet another aspect, the aromatic polycarbonate is a mixture of 20 to 80 weight percent or 40 to 60 weight percent interfacial polycarbonate and 80 to 20 weight percent or 60 to 40 weight percent molten polycarbonate, based on the weight of the aromatic polycarbonate.

[0029] Preferably, the aromatic polycarbonate in the composition according to the present invention is composed of interfacial polycarbonate, and has an end-capping level of at least 90 mol %. On the other hand, the aromatic polycarbonate in the composition according to the present invention is composed of molten polycarbonate, and has an end-capping level of at least 75 mol %, preferably at least 80 mol %, more preferably at least 85 mol %. The end-capping level can be at most 95 mol %, for example at most 90 mol %. In this respect, the end-capping level is considered to be the value measured for the aromatic polycarbonate of the composition. On the other hand, the aromatic polycarbonate can be a mixture of molten polycarbonate and a polycarbonate not made using a melting method (such as an interfacial method), as long as the end-capping level is at least 75 mol %.

[0030] The aromatic polycarbonate may have a melt volume rate (MVR) measured according to ISO 1133 (300° C., 1.2 kg) of 1 to 50 cc / 10 min, in particular 2 to 30 cc / 10 min, for example 10-15 cc / 10 min. The aromatic polycarbonate may comprise two or more aromatic polycarbonates having different melt volume rates (i.e., molecular weights). The aromatic polycarbonates of the mixture may all be bisphenol A polycarbonate homopolymers. On the other hand, the aromatic polycarbonate may comprise a polycarbonate copolymer containing structural units of bisphenol A and structural units of another bisphenol.

[0031] Polyester

[0032] The polyester of the composition disclosed herein comprises at least 80% by weight, preferably at least 90% by weight, of polybutylene terephthalate (PBT), based on the weight of the polyester. More preferably, the polyester of the composition disclosed herein consists essentially of polybutylene terephthalate or consists of polybutylene terephthalate. The PBT may be a mixture of two or more different polybutylene terephthalates, for example a mixture of PBTs having mutually different intrinsic viscosities. The polyester may also comprise mechanically recycled PBT or PBT obtained from (chemically) recycled polyethylene terephthalate (PET). Polyesters such as PBT and PET themselves are well known to the skilled person.

[0033] The PBT may be a single polymer or may be a combination of two or more, preferably two, PBTs having mutually different properties. For example, the PBT may comprise a first PBT and a second PBT, each having a different intrinsic viscosity. Thus, the PBT in the composition of the present invention may be a blend of such a first and a second (or additional) PBT. In this regard, the intrinsic viscosity of the first PBT may be 1.1 to 1.4 dl / g and the intrinsic viscosity of the second PBT may be 0.6 to 0.8 dl / g.

[0034] According to the present invention, the polyester may have an intrinsic viscosity of 0.4 to about 2.0 dl / g measured in a 60:40 phenol / tetrachloroethane mixture at 23° C. In aspects where the polyester is a mixture, then this preferred feature applies to the mixture.

[0035] Preferably the polyester comprises at least 50 wt%, preferably at least 80 wt%, more preferably at least 90 or 95 wt% PBT based on the weight of the polyester. Preferably the polyester consists of PBT. Preferably PBT is the only polyester in the composition.

[0036] In one aspect, the polyester may further comprise an additional polyester miscible with PBT. Such polyesters include polyethylene terephthalate, polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polypropylene terephthalate (PPT), polycyclohexanedimethanol terephthalate (PCT), poly(cyclohexane-1,4-dimethylenecyclohexane-1,4-dicarboxylate) (also known as poly(1,4-cyclohexane-diethanol-1,4-dicarboxylate)) (PCCD) and copolyesters PCTG and PETG, preferably PET. According to this aspect of the invention, the composition preferably comprises 99 to 80 wt % PBT and 1 to 20 wt % of one or more of the additional polyesters, based on the weight of the polyester. Preferably the additional polyester is PET.

[0037] The polyester may also comprise mechanically recycled PBT or PBT obtained from renewable resources. Polyesters such as PBT are well known to the skilled person per se. The PBT used in the composition of the invention may, for example, be a polymer comprising polymerized units derived from terephthalic acid or its diester, such as dimethyl terephthalate, and polymerized units derived from butanediol, such as 1,4-butanediol.

[0038] In any aspect where the polyester comprises PBT, a mixture of PBT, and a polyester that is not PBT, then the intrinsic viscosity of the polyester is preferably from 0.6 to 1.4 dl / g. The PBT may have a carboxyl end group content of from 10 to 80 mmol / kg, preferably from 20 to 60 mmol / kg, more preferably from 20 to 40 mmol / kg, as determined according to ASTM D7409-15.

[0039] According to the invention, the polyester preferably does not contain or consist of polylactic acid, such as the material identified in particular as “PLA” in US Pat. No. 9,920,198.

[0040] According to the present invention, the thermoplastic composition preferably does not contain polylactic acid, such as the material identified in particular as "PLA" in US Pat. No. 9,920,198.

[0041] Hydrolysis Stabilizer

[0042] According to the present invention, the thermoplastic composition of the present invention with improved hydrolytic stability comprises 0.1 to 10 wt. %, preferably 0.5 to 3 wt. %, based on the weight of the composition, of a hydrolysis stabilizer composition comprising at least one compound containing epoxy functional groups. Preferably, the composition comprises at least 80 wt. %, preferably 90 wt. % to 100 wt. %, based on the weight of the hydrolysis stabilizer composition, of at least one compound containing epoxy functional groups.

[0043] The epoxy compound may have one or more epoxy functional groups. The term "multifunctional epoxy compound" is defined to include compounds having at least two epoxy functional groups. A preferred difunctional epoxy compound is 3,4-epoxycyclohexyl-3,4-epoxycyclohexyl carboxylate, which is commercially available as ERL-4221 epoxy resin from Union Carbide. Examples of other preferred difunctional epoxy compounds are bis(3,4-epoxycyclohexylmethyl)adipate, vinylcyclohexene diepoxide, bisphenol diglycidyl ether, diglycidyl adducts of amides, diglycidyl adducts of carboxylic acids, and the like.

[0044] Other hydrolysis stabilizers containing epoxy functional groups can be ethylene and / or styrene copolymers, which contain repeating units derived from ethylene and epoxy comonomers, and the epoxy comonomers include, for example, glycidyl acrylate, glycidyl methacrylate, glycidyl butyl acrylate, glycidyl vinyl ether, or a combination of two or more thereof. Frequently used ethylene and / or styrene copolymers may further contain repeating units derived from esters of unsaturated carboxylic acids (including (meth) acrylates or (meth) acrylic acid C1-C8 alkyl esters, or a combination of two or more thereof). "(Meth) acrylate" refers to acrylate, alkyl acrylate, methacrylate, or a combination of two or more thereof. Examples of alkyl acrylates include methyl acrylate, ethyl acrylate and butyl acrylate.

[0045] The ethylene and / or styrene copolymers may also comprise, consist essentially of, or consist of repeating units derived from ethylene and / or styrene and an epoxy comonomer (including, for example, glycidyl esters of acrylic acid or methacrylic acid, glycidyl vinyl ether, or combinations thereof) and an additional comonomer (e.g., carbon monoxide). Such epoxy compounds are commercially available or may be prepared by techniques well known to those skilled in the art.

[0046] On the other hand, the hydrolysis stabilizer composition also contains at least one compound containing an imide functional group. These compounds are known and can be obtained commercially, for example, Stabaxol P (a product of Rhein Chemie Corporation), and can be prepared by known methods (e.g. European Patent No. 582983; Japanese Patent Publication No. 33279 / 1972; Journal of Organic Chemistry, 28, 2069-2075 91963; Chemical Review 1981, Vol. 81, No. 4, 619-621; Journal of Applied Polymer Science, 1977, Vol. 21, 1999-2008, all incorporated herein by reference). Preferably, the composition contains at least 80% by weight, preferably 90% to 100% by weight of the total amount of one or more compounds containing epoxy functional groups and one or more compounds containing imide functional groups, based on the weight of the hydrolysis stabilizer composition.

[0047] Impact modifiers

[0048] The thermoplastic composition of the present invention optionally comprises an impact modifier. The amount of the impact modifier may be 0 to 15 wt % based on the weight of the composition. Preferably, the impact modifier is included in the composition in an amount of 2 to 12 wt %, more preferably 4 to 8 wt %.

[0049] Suitable impact modifiers are typically high molecular weight elastomeric materials derived from olefins, monovinyl aromatic monomers, acrylic and methacrylic acids and their ester derivatives, and conjugated dienes. The polymers formed from the conjugated dienes can be fully or partially hydrogenated. The elastomeric material can be in the form of a homopolymer or copolymer, including random, block, radial block, grafted, and core-shell copolymers. Combinations of impact modifiers are also used.

[0050] The impact modifier comprises or consists of at least one of an acrylonitrile-butadiene-styrene (ABS) polymer and / or a methyl methacrylate-butadiene-styrene (MBS) polymer.

[0051] Other components

[0052] The thermoplastic composition disclosed herein comprises 0 to 5% by weight of other components, which are preferably selected from reinforcing fillers or non-reinforcing fillers, such as talc, calcium carbonate, glass flakes, glass fibers, etc., antifogging agents, plasticizers, flow enhancing additives, lubricants, pigments, dyes, flame retardants, nucleating agents, heat stabilizers, UV absorbers, UV stabilizers, dispersants, surfactants, antistatic agents, slip agents, or a combination of two or more thereof. Such additional components are known per se to the skilled person.

[0053] Preferably, the other components according to the present invention comprise 0.01 to 1 wt. % of a compound selected from Group IB metal phosphates and Group IIB metal phosphates, based on the weight of the composition. Preferably, the compound is selected from Group IB and / or Group IIB metal acid phosphates, metal acid pyrophosphates and metal polyphosphates, more preferably the catalyst quencher is zinc phosphate. The compound is used as a quencher of the catalyst or catalyst residues in the polyester.

[0054] Preferably, the other components comprise 0.01 to 1 wt %, preferably 0.03 to 0.5 wt %, based on the weight of the composition, of a compound containing at least one of an alkali metal cation or an alkaline earth metal cation and a halogen anion, the compound preferably being selected from one or more of lithium fluoride, lithium iodide, potassium bromide, potassium iodide, sodium dihydrogen phosphate, sodium acetate, sodium benzoate, sodium hexanoate, sodium stearate, sodium ascorbate and magnesium hexanoate.

[0055] Composition

[0056] The combination of specific types and amounts of materials constituting the thermoplastic composition results in property characteristics in terms of, inter alia, water stability, mechanical and thermal properties. The examples and comparative examples disclosed herein provide the skilled person with materials that fall within and do not fall within the scope of the present invention, respectively, thereby forming a basis for developing further embodiments according to the present invention without undue burden.

[0057] According to the present invention, the thermoplastic composition comprises, based on the weight of the composition,

[0058] (A) 40 to 70% by weight of an aromatic polycarbonate,

[0059] (B) 20 to 40% by weight of polyester,

[0060] (C) 0.1 to 10% by weight of a hydrolysis stabilizer composition comprising at least one compound containing epoxy functional groups,

[0061] (D) 0 to 15 wt. % of an impact modifier,

[0062] (E) 0 to 5% by weight of other components,

[0063] However, the total amount of (A) to (E) is 100% by weight.

[0064] The amount of component (A) may be 50 to 70% by weight.

[0065] The amount of component (B) may be 25 to 35% by weight.

[0066] The amount of component (C) may be 0.5 to 3% by weight.

[0067] The amount of component (D) may be from 2 to 12% by weight.

[0068] The amount of component (E) may be from 0.01 to 3% by weight.

[0069] Preferably, component (B) comprises or consists of polybutylene terephthalate. In another aspect, component (B) comprises or consists of polyethylene terephthalate.

[0070] For the avoidance of doubt, the skilled person will appreciate that the total weight of the composition will be 100 wt % and that any combination of materials that does not add up to 100 wt % is impractical and not in accordance with the present invention.

[0071] According to the present invention, the thermoplastic composition is selected to have the following combination:

[0072] At least 50 kJ / m 2 Initial notched Izod impact measured at 23°C according to ISO180-1A,

[0073] A notched Izod impact retention of at least 70% as determined by the method set out in the specification,

[0074] A heat distortion temperature of at least 90°C, preferably 90°C to 120°C, measured in accordance with ISO 75A flat method under a load of 0.45 MPa.

[0075] In preferred aspects, the thermoplastic composition exhibits a notched Izod impact retention that is at least about 5%, preferably at least about 10%, and more preferably at least about 20% greater than the same composition but without component (D).

[0076] Preferred ranges for the amounts of the components can be combined with preferred ranges for the properties of the composition without limitation, provided that they certainly fall within the scope of the invention as defined herein in its broadest form. That is, preferred ranges for one or more of the amounts and / or types of the components making up the thermoplastic composition can be combined with preferred ranges for one or more properties of the thermoplastic composition, and all such combinations are considered to be disclosed herein.

[0077] The composition can be made by various methods known in the art. For example, the polycarbonate, polyester and other components and any optional fillers are first blended in a high-speed mixer or mixed by hand. The blend is then fed into the throat of a twin-screw extruder via a hopper.

[0078] Preferably, the thermoplastic composition is prepared by a process comprising the steps of:

[0079] a) combining the polyester with a hydrolysis stabilizer composition, an optional impact modifier, and optional other components in a first melt mixing device to form a stabilized polyester,

[0080] b) combining the stabilized polyester with a polycarbonate in a second melt mixing device.

[0081] The product from the second melt mixing device can be fed to an extruder. The extruder is set with a barrel temperature of 150° C. to 260° C. The extrudate can be immediately cooled in a water bath and pelletized. The pellets so prepared can be 0.6 cm long or shorter as required. Such pellets can be used for subsequent molding, shaping or forming.

[0082] Also provided are shaped, formed or molded articles comprising the composition. The composition can be molded into articles by various methods such as injection molding, extrusion and thermoforming. Some examples of articles include automotive and vehicle body panels such as bumper covers and bumpers or housings for electrical equipment.

[0083] Therefore, the present invention relates to an article comprising or consisting of a thermoplastic composition or a thermoplastic composition obtainable by the process disclosed herein, wherein preferably the article is an automotive interior article or a housing for an electrical device.

[0084] More specifically, the present invention relates to a vehicle body part or a housing of an electrical device comprising a thermoplastic composition disclosed herein or consisting of a thermoplastic composition disclosed herein. Likewise, the present invention relates to an article comprising or constituting any one or more selected from the following: an instrument panel, a cup holder, a glove box, an instrument panel, an instrument panel carrier, a door covering, a door fixing, an armrest, a column covering, a seat covering, a trunk covering, and a component used in a heating, ventilation and / or air conditioning device. In addition, the present invention relates to a vehicle or an electrical device comprising the vehicle body part or the housing. The present invention relates to the use of a thermoplastic composition or a thermoplastic composition obtainable by the method disclosed herein in the manufacture of an article (preferably an automotive part, more preferably an automotive interior part).

[0085] The invention will now be further illustrated based on the following non-limiting examples.

[0086] Test methods

[0087] Example

[0088] The samples were molded by injection molding on a L&T ASWA 100T injection molding machine at 260° C., the mold temperature setting for all compositions was kept at 100° C. The components of the compositions and their sources are listed in Table 1.

[0089] Table 1: Components of the composition and their sources

[0090]

[0091]

[0092]

[0093]

[0094]

[0095] The amounts in Table 2 are weight percent based on the total weight of the composition. In all examples, the total amount of the components is equal to 100 weight percent. Table 2 shows that thermoplastic compositions comprising PC / PBT and impact modifiers, i.e., ABS or MBS, do not show the desired hydro-aging properties in terms of notched Izod impact retention measured according to the method described above in the absence of the hydrolysis stabilizer of the present invention (CE1 to CE4). However, in the presence of a hydrolysis stabilizer composition comprising a compound containing an epoxy functional group, it is shown that the composition shows the desired hydro-aging properties in terms of notched Izod impact retention measured according to the method described above (E1 to E14). Different compounds containing epoxy functional groups have been explored to demonstrate the present invention. In the presence of sodium stearate and / or other additives (such as carbon black), the composition shows the desired hydro-aging properties and a balance of thermal properties in terms of HDT. Table 2 also shows that zinc phosphate-based quenchers are superior to sodium phosphate-based quenchers to achieve the desired properties described in the present invention (CE5 vs. E1).

[0096] Furthermore, a combination of two different hydrolysis stabilizers, one with epoxy functionality and the other with imide functionality, also showed similar effects according to the present invention (E15 and E16). E17 to E20 show that PC / PBT compositions containing hydrolysis stabilizer compounds containing epoxy functionality can achieve the properties described by the present invention even in the absence of an impact modifier. E21 and E22 illustrate the present invention when PET and PC are added to the composition instead of PBT. E23 to E25 are experiments conducted according to the present invention using molten PC with different end-capping levels in thermoplastic compositions instead of using interfacial PC and show the desired hydro-aging properties in terms of notched Izod impact retention as determined by the method described in the specification.

Claims

1. A thermoplastic composition comprising: (A) 40 to 70% by weight of an aromatic polycarbonate, (B) 20 to 40% by weight of polyester, (C) 0.1 to 10% by weight of a hydrolysis stabilizer composition comprising at least one compound containing epoxy functional groups, (D) 0 to 15 wt. % of an impact modifier, (E) 0 to 5% by weight of other components, in, The total amount of (A) to (E) is 100 wt%, and wherein the composition is selected to have the following combination: At least 50 kJ / m 2 Initial notched Izod impact measured at 23°C according to ISO180-1A, A notched Izod impact retention of at least 70% as determined by the method set out in the specification, Heat distortion temperature of at least 90°C measured in accordance with ISO 75A lay-flat method under a load of 1.8 MPa.

2. The thermoplastic composition according to claim 1, wherein the polyester does not comprise or consists of polylactic acid.

3. Thermoplastic composition according to claim 1 or 2, wherein the polyester comprises at least 80% by weight, preferably at least 90% by weight, based on the weight of the polyester, of poly(butylene terephthalate), wherein preferably the polyester consists of poly(butylene terephthalate).

4. The thermoplastic composition according to any one or more of claims 1 to 3, wherein the impact modifier comprises at least one of an acrylonitrile-butadiene-styrene (ABS) polymer and a methacrylate-butadiene-styrene (MBS) polymer.

5. Thermoplastic composition according to any one or more of claims 1 to 4, wherein the hydrolysis stabilizer composition additionally comprises at least one compound containing imide functional groups.

6. The thermoplastic composition of any one or more of claims 1 to 5, wherein the aromatic polycarbonate comprises two or more aromatic polycarbonates having different melt volume rates and / or wherein the polyester comprises two or more poly(butylene terephthalate)s having different intrinsic viscosities.

7. Thermoplastic composition according to any one or more of claims 1 to 6, wherein the aromatic polycarbonate comprises or consists of bisphenol A polycarbonate or a mixture of bisphenol A polycarbonates, preferably wherein at least a portion of the bisphenol A polycarbonate is prepared by melt transesterification of bisphenol A and diphenyl carbonate.

8. The thermoplastic composition according to any one or more of claims 1 to 7, wherein the aromatic polycarbonate has a weight average molecular weight of 15,000 to 60,000 g / mol as determined using gel permeation chromatography with polystyrene standards and / or wherein the polyester has an intrinsic viscosity of 0.4 to about 2.0 dl / g measured in a 60:40 phenol / tetrachloroethane mixture at 23°C.

9. The thermoplastic composition according to any one or more of claims 1 to 8, wherein component (E) comprises 0.01 to 1 wt. %, based on the weight of the composition, of a compound selected from Group IB metal phosphates and Group IIB metal phosphates.

10. Thermoplastic composition according to any one or more of claims 1 to 9, wherein component (E) comprises 0.01 to 1% by weight, based on the weight of the composition, of a compound containing at least one of an alkali metal cation or an alkaline earth metal cation and a halogen anion, the compound preferably being selected from one or more of lithium fluoride, lithium iodide, potassium bromide, potassium iodide, sodium dihydrogen phosphate, sodium acetate, sodium benzoate, sodium hexanoate, sodium stearate, sodium ascorbate and magnesium hexanoate.

11. Process for producing a thermoplastic composition according to any one or more of claims 1 to 10, comprising the steps of: a) combining the polyester with the hydrolysis stabilizer composition and optionally other components in a first melt mixing device to form a stabilized polyester, b) combining the stabilized polyester with a polycarbonate and optionally an impact modifier in a second melt mixing device.

12. Article comprising or consisting of the thermoplastic composition according to any one or more of claims 1 to 10 or obtainable by the process according to claim 11, wherein preferably the article is an automotive interior article or a housing for an electrical device.

13. The article according to claim 12, wherein the article is contained in or constitutes any one or more selected from the following: instrument panels, cup holders, glove boxes, instrument panels, instrument panel brackets, door coverings, door fixings, armrests, pillar coverings, seat coverings, trunk coverings, and components for heating, ventilation and / or air conditioning equipment.

14. A vehicle or electrical equipment comprising an article according to claim 12 or 13.

15. Use of a thermoplastic composition according to any one or more of claims 1 to 10 or obtainable by a process according to claim 11 for the manufacture of an article, preferably an automotive part, more preferably an automotive interior part.

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