POLYMER COMPOSITION COMPRISING A (METH)ACRYLIC POLYMER

Abstract

The present invention relates to a polymer composition comprising: (a) 54.0-79.0 wt % of a (meth)acrylic polymer; (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (II) and (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III), wherein n=0 or 1; with regard to the total weight of the polymer composition. Such polymer composition provides a desired high heat resistance and good scratch resistance.

##STR00001##

Claims

1. A polymer composition comprising: (a) 54.0-79.0 wt % of a (meth)acrylic polymer; (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I): ##STR00029## and polymeric units according to formula (II): ##STR00030## and (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III): ##STR00031## wherein n=0 or 1; with regard to the total weight of the polymer composition.

2. The polymer composition according to claim 1 comprising 2.0-8.0 wt % of the copolymer (c) with regard to the total weight of the polymer composition.

3. The polymer composition according to claim 1 wherein the (meth)acrylic polymer (a) comprises 95.0% by weight, with regard to the total weight of the (meth)acrylic polymer (a), of polymeric units according to formula IV: ##STR00032## in which: R1 is hydrogen or a hydrocarbon moiety comprising 1-4 carbon atoms; R2 is a hydrocarbon moiety comprising 1-4 carbon atoms; and R3 is a hydrocarbon moiety comprising 1-4 carbon atoms.

4. The polymer composition according to claim 1 wherein the (meth)acrylic polymer (a) is a polymer prepared using 95% by weight with regard to the total weight of the monomers used of one or more monomers selected from methyl acrylate, methyl-2-methyl acrylate, methyl-2-ethyl acrylate, methyl-2-propyl-acrylate, methyl-2-butyl acrylate, ethyl acrylate, ethyl-2-methyl acrylate, ethyl-2-ethyl acrylate, ethyl-2-propyl acrylate, ethyl-2-butyl acrylate, propyl acrylate, propyl-2-methyl acrylate, propyl-2-ethyl acrylate, propyl-2-propyl acrylate, propyl-2-butyl acrylate, butyl acrylate, butyl-2-methyl acrylate, butyl-2-ethyl acrylate, butyl-2-propyl acrylate, butyl-2-butyl acrylate, t-butyl-2-methyl acrylate, isobutyl-2-methyl acrylate, isopropyl-2-methyl acrylate, or combinations thereof.

5. The polymer composition according to claim 1 wherein the (meth)acrylic polymer (a) is selected from polymethylmethacrylate (PMMA), polybutylmethacrylate (PBMA), poly(methylmethacrylate-ethylacrylate) (PMMA-co-EA), polyethyl acrylate (PEA), polybenzyl methacrylate, poly(n-butyl acrylate), poly(t-butyl acrylate), poly(cyclohexyl methacrylate), poly(1,3-dimethylbutyl methacrylate), poly(3,3-dimethylbutyl methacrylate), poly(diphenylethyl methacrylate), poly(diphenylmethyl methacrylate), poly(dodecyl methacrylate), poly(2-ethylbutyl methacrylate), polyethyl methacrylate, poly(trimethylpropyl methacrylate), poly(n-propylmethacrylate), polyphenyl methacrylate, poly(1-phenylethyl methacrylate), polyoctyl methacrylate, polyneopentyl methacrylate, poly(1-methylpentyl methacrylate), polymethylbutyl methacrylate, polylauryl methacrylate, polyisopropyl methacrylate, polyisopentyl methacrylate, or combinations thereof.

6. The polymer composition according to claim 1 wherein the (meth)acrylic polymer (a) is selected from polymethylmethacrylate (PMMA), polybutylmethacrylate (PBMA), poly(methylmethacrylate-ethylacrylate) (PMMA-co-EA), or polyethyl acrylate (PEA).

7. The polymer composition according to claim 1 wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA).

8. The polymer composition according to claim 1 wherein the polymer composition is prepared by melt mixing of a mixture comprising (meth)acrylic polymer (a), copolymer (b) and copolymer (c) in a melt extruder, wherein the melt extruder comprises: (i) an inlet for feeding the mixture; (ii) a barrel comprising one or more extruder screw(s) each comprising a tip; (iii) one or more opening(s) for removing the obtained polymer composition from the extruder; and (iv) a volume of space in the area between the tip(s) of the extruder screw(s) and the opening(s) for removing the obtained polymer composition wherein during the melt mixing the temperature of the polymer composition in the volume of space (iv) is 235 C. and 255 C.

9. The polymer composition according to claim 1 wherein the polymer composition comprises 64.0-74.0 wt % of (meth)acrylic polymer (a), 25.0-35.0 wt % of copolymer (b), and 1.0-8.0 wt % of copolymer (c), with regard to the total weight of the polymer composition.

10. The polymer composition according to claim 1 wherein the copolymer (b) comprises 5.0 wt % of polymeric units according to formula (II), with regard to the total weight of the copolymer (b).

11. The polymer composition according to claim 1 wherein the copolymer (c) is prepared by reacting copolymer (b) with p-amino benzoic acid.

12. The polymer composition according to claim 1 wherein: the (meth)acrylic polymer (a) has a melt mass flow rate as determined in accordance with ISO 1133-1 (2011), at 230 C. using a load of 3.80 kg, of 0.1 and 20.0 g/10 min; and/or the copolymer (b) has an intrinsic viscosity of 0.20 and 1.00 dl/g as determined in accordance with ISO 1628-1:2009.

13. The polymer composition according to claim 1 wherein the polymer composition has: a heat deflection temperature determined as the temperature of deflection under load, in accordance with ISO 75-2 (2013), method B, of 110 C.; a Vicat B softening temperature as determined in accordance with ISO 306 (2013), using a force of 50 N and a heating rate of 120 K/h of 120 C.; and/or a Yellowness Index as determined in accordance with ASTM E313 (2010) of 5.0.

14. An article produced using the polymer composition according to claim 1.

15. An article according to claim 14 having a residual scratch depth as determined in accordance with ASTM D7187 (2010) of 1500 nm.

Description

[0039] In certain embodiments, the copolymer (c) also comprises polymeric units according to formula (II). For example, the copolymer (c) may comprise 5 wt % of polymeric units according to formula (II), with regard to the total weight of the copolymer (c). Alternatively, the copolymer (c) may comprise 5.0 wt % and 20.0 wt % of polymeric units according to formula (II), alternatively 7.5 wt % and 15.0 wt %, with regard to the total weight of copolymer (c). For example, the copolymer (c) may comprise 7.5 and 15.0 wt % of polymeric units according to formula (II) with regard to the total weight of the copolymer (c).

[0040] In a particular embodiment, the copolymer (c) comprises 15.0 wt % and 25.0 wt % of polymeric units according to formula (III) and 7.5 wt % and 15.0 wt % of polymeric units according to formula (II).

[0041] The copolymer (c) may in an exemplary embodiment be prepared by melt blending of the copolymer (b) with p-amino benzoic acid, wherein the copolymer (b) and the p-amino benzoic acid react in the melt to obtain the copolymer (c). The copolymer (c) may also be referred to as a styrene-maleimide copolymer or SMI. The reactive melt blending of the copolymer (b) and the p-amino benzoic acid preferably is performed under such conditions that essentially all polymeric units according to formula (II) are converted into polymeric units according to formula (III). For example, the conversion of essentially all polymeric units according to formula (II) may be understood as to result in less than 100 ppm of units according to formula (II) remaining in the copolymer (c), preferably less than 75 ppm.

[0042] In a certain embodiment, the copolymer (c) is prepared by reacting the copolymer (b) with p-amino benzoic acid. Such reaction may for example be performed in a melt extruder.

[0043] The use of such copolymer (c) in the polymer composition according to the present invention contributes to the achievement of a desired high heat resistance. The use of such copolymer (c) in such quantities contributes to the achievement of a desired high heat resistance whilst maintaining good optical properties such as transparency and good surface properties, as well as good mechanical properties.

[0044] It is preferred that the polymer composition according to the present invention comprises 80.0 wt % with regard to the total weight of the polymer composition of the sum of (meth)acrylic polymer (a), copolymer (b) and copolymer (c), more preferably 90.0 wt %, even more preferably 95.0 wt %, or 99.0 wt %.

[0045] The polymer composition according to the present invention preferably comprises 64.0-74.0 wt % of (meth)acrylic polymer (a), 25.0-35.0 wt % of copolymer (b), and 1.0-8.0 wt % of copolymer (c), with regard to the total weight of the polymer composition.

[0046] The polymer composition may optionally comprise further ingredients such as antioxidants. These antioxidants may for example be phenolic antioxidants and/or phosphite antioxidants. A stabiliser composition comprising one or more phenolic antioxidant(s) and one or more phosphite antioxidant(s) may for example be used. Phenolic antioxidants may for example be selected from monophenolic antioxidants, i.e. antioxidants containing one phenolic group per molecule, bisphenolic antioxidants i.e. antioxidants containing two phenolic groups per molecule, and polyphenolic antioxidants, i.e. antioxidants containing more than two phenolic groups per molecule, including 1,1,3-tris(2-methyl-4-hydroxy-5-t-butyl phenyl) butane, pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, and 1,3,5-tris(4-t-butyl-2,6-dimethyl-3-hydroxybenzyl)isocyanurate.

[0047] Preferably, the phenolic antioxidant is pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate.

[0048] Phosphite antioxidants may for example be selected from trisnonylphenyl phosphite, trilauryl phosphite, tris(2,4-di-t-butylphenyl)phosphite, triisodecyl phosphite, diisodecyl phenyl phosphite, diphenyl isodecyl phosphite, and triphenyl phosphite. Preferably, the phosphite antioxidant is tris(2,4-di-t-butylphenyl)phosphite.

[0049] Preferably, the stabiliser composition comprises pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate.

[0050] The polymer composition may for example comprise 0.10 and 1.00 wt % of antioxidant, with regard to the total weight of the polymer composition, preferably 0.20 and 0.50 wt %.

[0051] The polymer composition may optionally comprise further ingredients such as heat stabilisers. The heat stabilisers may for example be a nitrogen-containing compounds. Such nitrogen-containing heat stabilisers may for example be one or more selected from the list consisting of aminotriazine compounds, allantoin, hydrazides, polyamids, melamines, and/or mixtures thereof.

[0052] The nitrogen-containing compound can be a low molecular weight compound or a high molecular weight compound. Examples of low molecular weight nitrogen-containing compounds can include an aliphatic amine (e.g., monoethanolamine, diethanolamine, and tris-(hydroxymethyl)aminomethane), an aromatic amine (e.g., an aromatic secondary or tertiary amine such as o-toluidine, p-toluidine, p-phenylenediamine, o-aminobenzoic acid, p-aminobenzoic acid, ethyl o-aminobenzoate, or ethyl p-aminobenzoate), an imide compound (e.g., phthalimide, trimellitimide, and pyromellitimide), a triazole compound (e.g., benzotriazole), a tetrazole compound (e.g., an amine salt of 5,5-bitetrazole, or a metal salt thereof), an amide compound (e.g., a polycarboxylic acid amide such as malonamide or isophthaldiamide, and p-aminobenzamide), hydrazine or a derivative thereof (e.g., an aliphatic carboxylic acid hydrazide such as hydrazine, hydrazone, a carboxylic acid hydrazide (stearic hydrazide, 12-hydroxystearic hydrazide, adipic dihydrazide, sebacic dihydrazide, or dodecane diacid dihydrazide; and an aromatic carboxylic acid hydrazide such as benzoic hydrazide, naphthoic hydrazide, isophthalic dihydrazide, terephthalic dihydrazide, naphthalenedicarboxylic dihydrazide, or benzenetricarboxylic trihydrazide)), a polyaminotriazine (e.g., guanamine or a derivative thereof, such as guanamine, acetoguanamine, benzoguanamine, succinoguanamine, adipoguanamine, 1,3,6-tris(3,5-diamino-2,4,6-triazinyl)hexane, phthaloguanamine or CTU-guanamine, melamine or a derivative thereof (e.g., melamine, and a condensate of melamine, such as melam, melem or melon)), a salt of a polyaminotriazine compound containing melamine and a melamine derivative with an organic acid, a salt of a polyaminotriazine compound containing melamine and a melamine derivative with an inorganic acid, uracil or a derivative thereof (e.g., uracil, and uridine), cytosine or a derivative thereof (e.g., cytosine, and cytidine), guanidine or a derivative thereof (e.g., a non-cyclic guanidine such as guanidine or cyanoguanidine; and a cyclic guanidine such as creatinine), and urea or a derivative thereof.

[0053] The polymer composition may for example comprise 0.10 and 1.00 wt % of heat stabilisers, with regard to the total weight of the polymer composition, preferably 0.20 and 0.50 wt %.

[0054] It is particularly preferred that the polymer composition according to the invention has: [0055] a heat deflection temperature as determined as determined as the temperature of deflection under load, in accordance with ISO 75-2 (2013), method B, of 110 C.; [0056] a Vicat B softening temperature as determined in accordance with ISO 306 (2013), using a force of 50 N and a heating rate of 120 K/h of 120 C.; and/or [0057] a Yellowness Index as determined in accordance with ASTM E313 (2010) of 5.0.

[0058] The invention also in a particular embodiment relates to an article produced using the polymer composition according to the invention. In particular, it is preferred that such articles has a residual scratch depth as determined in accordance with ASTM D7187 (2010) of 1500 nm.

[0059] The polymer composition according to the present invention may for example be prepared by melt mixing of a mixture comprising (meth)acrylic polymer (a), copolymer (b) and copolymer (c) in a melt extruder, wherein the melt extruder comprises: [0060] (i) an inlet for feeding the mixture; [0061] (ii) a barrel comprising one or more extruder screw(s) each comprising a tip; [0062] (iii) one or more opening(s) for removing the obtained polymer composition from the extruder; and [0063] (iv) a volume of space in the area between the tip(s) of the extruder screw(s) and the opening(s) for removing the obtained polymer composition [0064] wherein during the melt mixing the temperature of the polymer composition in the volume of space (iv) is 235 C. and 255 C.

[0065] Suitable melt extruders for preparation of the polymer compositions are well known. It is preferred that the melt extruder comprises at least two extruder screws wherein the extruder screws are co-rotating or counter-rotating, and wherein the melt extruder is designed such to ensure the feed mixture to be transported from the feed inlet to the opening for removing the obtained polymer composition and to ensure the feed mixture to be subjected to sufficient heat to result in the polymer composition in the volume of space (iv) to have a temperature of 235 C. and 255 C. It is preferred that the melt extruder comprises two extruder screws wherein the extruder screws are co-rotating. Heat may be supplied to the feed mixture in the melt extruder by in the form of shear induced by rotation of the extruder screws and/or by supply of extemal heat such as via a heating jacket positioned around the barrel of the melt extruder.

[0066] Preferably, the temperature of the polymer composition during the melt mixing in the volume of space (iv) is 240 C. and 250 C.

[0067] A polymer composition according to the present invention may for example by prepared via a process comprising the following steps in this order: [0068] continuously feeding the mixture comprising (a), (b) and (c) and optionally further ingredients to the inlet (i) of a melt extruder; [0069] subjecting the mixture to rotation of the screws such as to result in the transportation of the mixture towards the opening(s) (iii); [0070] continuously removing the obtained polymer composition from the opening(s) (iii); and [0071] cooling the obtained polymer composition to obtain a solid composition.

[0072] In addition to inlet (i), the melt extruder may optionally have further inlet(s) for feeding the mixture of ingredients to the melt extruder.

[0073] The obtained polymer composition may be removed from the extruder from the opening(s) (iii), wherein the opening(s) may be present in the form of circular openings or holes. The obtained polymer composition may leave the melt extruder in the form of strands, wherein the polymer composition upon leaving the extruder is in molten state. The molten strands leaving the extruder may be subjected to cooling to a temperature below the melting point of the polymer composition. For example, the molten strands may be cooled to below 100 C. this cooling may be achieved by subjecting the molten strands to water having a temperature of for example 50 C.

[0074] It is preferred that the process for preparation of the polymer composition according to the invention is a continuous process.

[0075] An embodiment of the invention relates to a polymer composition comprising: [0076] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0077] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00008## [0078] and polymeric units according to formula (II):

##STR00009## [0079] and [0080] (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00010##

[0081] with regard to the total weight of the polymer composition;

[0082] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises 15.0 wt % and 25.0 wt % of polymeric units according to formula (III) and Z 7.5 wt % and 15.0 wt % of polymeric units according to formula (II).

[0083] In another embodiment, the invention relates to a polymer composition comprising: [0084] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0085] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00011## [0086] and polymeric units according to formula (II):

##STR00012## [0087] and [0088] (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00013##

[0089] with regard to the total weight of the polymer composition;

[0090] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises 15.0 wt % and 25.0 wt % of polymeric units according to formula (III) and 7.5 wt % and 15.0 wt/o of polymeric units according to formula (II).

[0091] In a particularly preferred embodiment, the present invention relates to a polymer composition comprising: [0092] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0093] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00014## [0094] and polymeric units according to formula (II):

##STR00015## [0095] and [0096] (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00016##

[0097] with regard to the total weight of the polymer composition;

[0098] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises less 100 ppm of units according to formula (II).

[0099] In a further particularly preferred embodiment, the present invention relates to a polymer composition comprising: [0100] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0101] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00017## [0102] and polymeric units according to formula (II):
and

##STR00018## [0103] (c) 1.0-10.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00019## [0104] with regard to the total weight of the polymer composition;

[0105] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises less 100 ppm of units according to formula (II);

[0106] wherein the polymer composition comprises 95.0 wt % with regard to the total weight of the polymer composition of the sum of (meth)acrylic polymer (a), copolymer (b) and copolymer (c).

[0107] In a further particularly preferred embodiment, the present invention relates to a polymer composition comprising: [0108] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0109] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I)

##STR00020## [0110] and polymeric units according to formula (II):

##STR00021##

[0111] and [0112] (c) 1.0-8.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00022##

[0113] with regard to the total weight of the polymer composition;

[0114] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises less 100 ppm of units according to formula (II);

[0115] wherein the polymer composition comprises 95.0 wt % with regard to the total weight of the polymer composition of the sum of (meth)acrylic polymer (a), copolymer (b) and copolymer (c).

[0116] In a further particularly preferred embodiment, the present invention relates to a polymer composition comprising: [0117] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0118] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00023## [0119] and polymeric units according to formula (II):

##STR00024##

[0120] and [0121] (c) 1.0-6.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00025##

[0122] with regard to the total weight of the polymer composition;

[0123] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises less 100 ppm of units according to formula (II);

[0124] wherein the polymer composition comprises 95.0 wt % with regard to the total weight of the polymer composition of the sum of (meth)acrylic polymer (a), copolymer (b) and copolymer (c).

[0125] In a further particularly preferred embodiment, the present invention relates to a polymer composition comprising: [0126] (a) 54.0-79.0 wt % of a (meth)acrylic polymer; [0127] (b) 20.0-45.0 wt % of a copolymer comprising polymeric units according to formula (I):

##STR00026## [0128] and polymeric units according to formula (II):

##STR00027##

[0129] and [0130] (c) 1.0-6.0 wt % of a copolymer comprising polymeric units according to formula (I) and polymeric units according to formula (III):

##STR00028##

[0131] with regard to the total weight of the polymer composition;

[0132] wherein the (meth)acrylic polymer (a) is polymethylmethacrylate (PMMA), the copolymer (b) comprises 10.0 wt % and 50.0 wt % of polymeric units according to formula (II), and wherein the copolymer (c) comprises less 100 ppm of units according to formula (II);

[0133] wherein the polymer composition comprises 95.0 wt % with regard to the total weight of the polymer composition of the sum of (meth)acrylic polymer (a), copolymer (b) and copolymer (c), and wherein copolymer (c) comprises 15.0 and 25.0 wt % of polymeric units according to formula (III) with regard to the total weight of the copolymer (c).

[0134] The invention will now be illustrated by the following non-limiting examples.

TABLE-US-00001 TABLE I Materials used PMMA SABIC 20HR, a polymethylmethacrylate, obtainable from SABIC SMA XIRAN SZ26120, a copolymer prepared using styrene and maleic anhydride, comprising 26 wt % of polymer units derived from maleic anhydride, obtainable from Polyscope, The Netherlands Terpolymer XIRAN IZ1018M, a copolymer comprising 10 wt % of polymer units derived from maleic anhydride, 18 wt % of polymer units derived from n-phenyl maleimide, and 72 wt % of polymer units derived from styrene, obtainable from Polyscope, The Netherlands

[0135] Preparation of SMI

[0136] A quantity of 200 g of SMA was mixed with 80 g p-amino benzoic acid. The obtained mixture was subjected to melt mixing using an intermeshing Coperion ZSK-25 twin-screw melt extruder equipped with a vacuum port at a melt temperature of 230 C. The barrel temperature was maintained at 230 C., and the screws were operated at a speed of 300 rpm, with a feed rate of 8 kg/h. The extrudate was cut into pellets and dried for 4 h at 80 C. The dried pellets were ground to obtain a powder which was washed with methanol to remove the unreacted p-aminobenzoic acid, and subsequently dried at 80 C. for another 24 h. The dried powder contained 65 ppm of polymer units derived from maleic anhydride.

[0137] Preparation of Polymer Compositions

[0138] Polymer compositions were prepared by melt mixing the formulations as presented in table II using an intermeshing Coperion ZSK-25 twin-screw melt extruder at a melt temperature of 235 C. The barrel temperature was maintained at 230 C., and the screws were operated at a speed of 300 rpm, with a feed rate of 8 kg/h. The extrudate was cut into pellets. The melt temperature was determined in the volume of space in the area between the tips of the extruder screws and the openings for removing the obtained polymer composition.

TABLE-US-00002 TABLE II formulations of polymer compositions Example PMMA SMA SMI Terpolymer 1 70.0 25.0 5.0 2 70.0 27.5 2.5 3 70.0 20.0 10.0 4 70.0 27.5 2.5 5 70.0 25.0 5.0 6 70.0 20.0 10.0 7 (C) 70.0 30.0 8 (C) 70.0 30.0 9 (C) 95.0 5.0 10 (C) 100.0

[0139] The values in table II are in parts by weight. Examples 1-6 represent the present invention; examples 7-10 are included for comparative purposes.

[0140] The polymer compositions obtained were subjected to testing of material properties, the results of which are listed in table III.

TABLE-US-00003 TABLE III material properties of polymer compositions Example Property Unit 1 2 3 4 5 6 7 8 9 10 T.sub.g C. 128 127 127 127 125 125 115 126 114 114 HDT C. 111 111 109 112 111 111 113 109 99 Vicat B C. 122 122 120 120 121 121 116 118 109 108 Transmission % 87 88 74 91 91 93 Haze % 3.5 3.2 10.5 3.0 2.6 2.3 YI 4.2 3.5 11.5 3.0 2.9 Impact kJ/m.sup.2 2.15 2.20 1.98 2.30 2.32 2.20 2.34 2.24 2.31 2.10 strength Residual nm 1449 1444 1552 1456 1432 1423 1264 1492 1289 depth Hardness GPa 0.27 0.27 0.27 0.27 0.27 0.27 0.27 0.27 0.26

[0141] Wherein:

[0142] T.sub.g is the glass transition temperature as determined in accordance with ISO 11357-2 (2013).

[0143] HDT is the heat deflection temperature as determined as the temperature of deflection under load, in accordance with ISO 75-2 (2013), method B.

[0144] Vicat B softening temperature was determined in accordance with ISO 306 (2013), using a force of 50 N and a heating rate of 120 K/h.

[0145] Transmission is the luminous transmittance as determined in accordance with ASTM D1003 (2000).

[0146] Haze was determined in accordance with ASTM D1003 (2000).

[0147] YI is the Yellowness Index as determined in accordance with ASTM E313 (2010).

[0148] Impact strength is the Izod impact strength as determined in accordance with ISO 180 (2000), notch type A, at 23 C.

[0149] Residual depth is the depth of scratches induced by the nano-scratching method as determined in accordance with ASTM D7187 (2010). Nano-scratch testing was done with an increased load of 0-120 mN using a Berkovich indenter with a tip diameter of 50 nm. Depth was measured at a load of 48 mN.

[0150] Hardness is determined in as the indentation hardness in accordance with ISO 14577-1 (2015). Hardness was determined using a Berkovich indenter with a tip diameter of 20 nm. Indentations were made with a constant strain rate of 0.05 s.sup.1 and indentation depth of 2 m.

[0151] The presented examples indicate that a polymer composition according to the present invention has a desirably good combination of heat resistance and scratch resistance, combined with amongst other good optical properties and impact strength.