Chemically resistant polycarbonate-polyester compositions, methods of manufacture, and articles thereof

1. A polymer composition comprising:

15 to 60 wt % of a polycarbonate;

30 to 60 wt % of a poly(1,4-cyclohexanedimethylene terephthalate);

0.05 to 35 wt % of a poly(carbonate-siloxane);

0.5 to 18 wt % of a thermoplastic poly(ester-ether) copolymer; and

0.5 to 8 wt % of an ethylene-alkyl (meth)acrylate copolymer, wherein alkyl is a C 1 -C 4 straight chain, unsaturated hydrocarbon group;

wherein the weight percentages are based on the total weight of the polymer composition.

2. The composition of claim 1 , wherein an article molded from the polymer composition has

a notched Izod impact strength greater than or equal to 650 J/m measured as per ASTM method D256 on a 3.2 millimeter (mm) thick sample; and

a resistance to break of at least 4 days measured as per ASTM D638 method at 50 mm/min after exposure to sunscreen under 1% strain at 23° C.

3. The composition of claim 1 , wherein an article molded from the polymer composition has

a melt volume rate of greater than 25 cm 3 /10 minutes, measured as per ASTM method D1238 at 300° C. and 1.2 kilograms; and

a heat distortion temperature of 75 to 90° C., measured as per ASTM method D648 on a 3.2 mm bar at 1.82 MPa.

4. The composition of claim 1 , wherein the ethylene-alkyl (meth)acrylate copolymer is ethylene-methyl acrylate copolymer or ethylene-ethyl acrylate copolymer, or a combination comprising at least one of the foregoing.

5. The composition of claim 4 , wherein the ethylene-methyl acrylate copolymer or ethylene-ethyl acrylate copolymer has an acrylate content of 15 to 30 wt %.

6. The composition of claim 1 , wherein the thermoplastic poly(ester-ether) copolymer comprises 40 to 90 wt % of a hard block comprising polybutylene terephthalate repeating units having an average molecular weight less than 250 g/mol and 60 to 90 wt % of polyoxyalkylene units having a number average molecular weight less of 400 to 6000 g/mole.

7. The composition of claim 1 , wherein the polycarbonate is a bisphenol-A polycarbonate having a weight average molecular weight between 15,000 and 30,000 g/mol.

8. The composition of claim 1 , wherein the poly(carbonate-siloxane) copolymer comprises 10 to 30 wt % of polysiloxane units.

9. The composition of claim 1 , wherein the poly(carbonate-siloxane) copolymer comprises the formula:

wherein x is 1 to 200, y is 1 to 90 and z is 1 to 600.

10. The composition of claim 1 , further comprising a filler, an antioxidant, a thermal stabilizer, a quencher, a colorant, a mold release agent, a light stabilizer, an ultraviolet light absorber, a plasticizer, a lubricant, an antistatic agent, a flame retardant, an anti-drip agent, or a combination comprising at least one of the foregoing.

11. The composition of claim 1 , comprising

32 to 47 wt % of the polycarbonate;

25 to 35 wt % of the polyester;

10 to 25 wt % of the poly(carbonate-siloxane)

5 to 15 wt % of the thermoplastic poly(ether-ester);

1 to 3 wt % of the ethylene-alkyl (meth)acrylate copolymer which comprises an ethylene-methyl acrylate copolymer or an ethylene-ethyl acrylate copolymer or a combination comprising at least one of the foregoing;

0.005 to 0.1 wt % of a quencher;

0.005 to 0.1 wt % of a mold release agent; and

0.1 to 0.2 wt % of one or more antioxidants.

12. A method of preparing a polymer composition, comprising:

melt blending the components of the polymer composition of claim 1 .

13. An article comprising the polymer composition of claim 1 .

14. The article of claim 13 , wherein the article is a sheet, a film, a multilayer sheet, a multilayer film, a molded part, an extruded profile, a fiber, a coated part, or a foam.

15. The article of claim 13 , having

a notched Izod impact strength greater than or equal to 650 J/m measured as per ASTM method D256 on a 3.2 millimeter (mm) thick sample; and

a resistance to break of at least 4 days measured as per ASTM D638 method at 50 mm/min after exposure to sunscreen under 1% strain at 23° C.

16. The article of claim 13 , having

a melt volume rate of greater than 25 cm 3 /10 minutes, measured as per ASTM method D1238 at 300° C. and 1.2 kilograms; and

a heat distortion temperature of between 75-90° C., measured as per ASTM method D648 on a 3.2 mm bar at 1.82 MPa.

17. The polymer composition of claim 1 , comprising:

20 to 56 wt % of the polycarbonate;

28 to 50 wt % of the poly(1,4-cyclohexanedimethylene terephthalate);

0.1 to 30 wt % of the poly(carbonate-siloxane);

1 to 13 wt % of the thermoplastic poly(ester-ether) copolymer; and

0.5 to 8 wt % of the ethylene-alkyl (meth)acrylate copolymer;

wherein the weight percentages are based on the total weight of the polymer composition.

18. The composition of claim 6 , wherein the thermoplastic poly(ester-ether) copolymer comprises 25 to 75% of the hard block comprising the polybutylene terephthalate repeating units and 75 to 25 wt % of the polyoxyalkylene units.

19. The composition of claim 11 , wherein:

the polycarbonate is a bisphenol A homopolycarbonate;

the polyester is poly(1,4-cyclohexanedimethylene terephthalate);

the poly(carbonate-siloxane) is of the formula

wherein x is 1 to 200, y is 1 to 90 and z is 1 to 600; and

the thermoplastic poly(ether-ester) comprises poly(butylene terephthalate/isophthalate) blocks and poly(C 1 -C 4 oxytetramethylene terephthalate) blocks.