Polysiloxane-polycarbonate compositions, and related methods and articles

1. A composition, comprising, based on the total weight of the polymer components in the composition,

1 to 40 wt. % of an aromatic polycarbonate;

30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer comprising

carbonate units of the formula

wherein at least 60 percent of the total number of R 1 groups are C 1-60 aromatic organic radicals and the balance thereof are aliphatic, alicyclic, or aromatic radicals, and

polysiloxane units derived from a dihydroxy polysiloxane of the formula

wherein

R is independently at each occurrence the same or different C 1-13 monovalent organic group,

E has an average value of 10 to 100,

M can be the same or different, and can be a halogen, cyano, nitro, C 1 -C 8 alkylthio, C 1 -C 8 alkyl, C 1 -C 8 alkoxy, C 2 -C 8 alkenyl, C 2 -C 8 alkenyloxy group, C 3 -C 8 cycloalkyl, C 3 -C 8 cycloalkoxy, C 6 -C 10 aryl, C 6 -C 10 aryloxy, C 7 -C 12 aralkyl, C 7 -C 12 aralkoxy, C 7 -C 12 alkylaryl, or C 7 -C 12 alkylaryloxy,

n is independently 0, 1, 2, 3, or 4, and

R 6 is a divalent C 2 -C 8 aliphatic group;

0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane units, based on the total weight of the polysiloxane-polyimide copolymer; wherein

a 3.2 mm thick molded sample comprising the composition has less than or equal to 8% haze and at least 80% luminous transmittance, measured in accordance with ASTM D1003-00, and

a 3.2 mm thick molded sample comprising the composition retains more than 50% of its initial notched Izod impact strength of 6 to 20 ft-lb/in at 23° C. after hydro-aging for 5 days at 100° C., measured in accordance with ASTM D256: 2004.

2. The composition of claim 1 , wherein a molded sample comprising the composition and having a thickness of 3.2 mm has a notched Izod impact strength after hydro-aging for 3 days at 100° C. of greater than 7 ft-lb/in at 23° C., measured in accordance with ASTM D256: 2004.

3. The composition of claim 1 , wherein a molded sample comprising the composition and having a thickness of 3.2 mm has a notched Izod impact strength at least 5% greater than the composition lacking the polysiloxane-polyetherimide, each measured in accordance with ASTM D256: 2004.

4. The composition of claim 1 , wherein a molded sample comprising the composition and having a thickness of 3.2 mm has less than or equal to 6% haze, measured according to ASTM D1003-00.

5. The composition of claim 1 , wherein a molded article comprising the composition and having a thickness of 3.2 mm has at least 80% luminous transmittance, measured according to ASTM D1003-00.

6. The composition of claim 1 , wherein a molded sample comprising the composition and having a thickness of 2.3 mm has a UL94 flammability rating of V0.

7. The composition of claim 1 , wherein the polycarbonate units are derived from bisphenol A.

8. The composition of claim 1 , wherein M is methoxy, n is 1, R 6 is a divalent C 1 -C 3 aliphatic group, R is methyl, and E has an average value of 10 to 60.

9. A composition, comprising, based on the total weight of the polymer components in the composition,

1 to 40 wt. % of an aromatic polycarbonate;

30 to 98.8 wt. % of a polysiloxane-polycarbonate block copolymer comprising

carbonate units of the formula

wherein at least 60 percent of the total number of R 1 groups are C 1-60 aromatic organic radicals and the balance thereof are aliphatic, alicyclic, or aromatic radicals, and

polysiloxane units of the formula

wherein R is independently the same or different C 1-13 monovalent organic group, and E has an average value of 10 to 100; and

0.1 to 10 wt. % of a polysiloxane-polyimide block copolymer comprising more than 20 wt. % polysiloxane units, based on the total weight of the polysiloxane-polyimide copolymer;

a 3.2 mm thick molded sample comprising the composition has less than or equal to 8% haze and at least 80% luminous transmittance, measured in accordance with ASTM D1003-00, and

a 3.2 mm thick molded sample comprising the composition retains more than 50% of its initial notched Izod impact strength of 6 to 20 ft-lb/in at 23° C. after hydro-aging for 5 days at 100° C., measured in accordance with ASTM D256: 2004;

wherein the polysiloxane-polyimide copolymer comprises polysiloxane blocks of the formula

wherein

each of R 11 and R 16 is divalent, and is independently a substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic group having 5 to 30 carbon atoms, a substituted or unsubstituted, saturated, unsaturated, or aromatic polycyclic group having 5 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms;

each R 12 to R 15 is monovalent, and is independently a substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic group having 5 to 30 carbon atoms, a substituted or unsubstituted, saturated, unsaturated, or aromatic polycyclic group having 5 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms;

V is a tetravalent linker and is a substituted or unsubstituted, saturated, unsaturated, or aromatic monocyclic or polycyclic group having 5 to 50 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms;

g is 1 to 30; and

d is 2 to 20.

10. The composition of claim 9 , wherein each of R 11 and R 16 is propyl, each R 12 to R 15 is methyl, and V is of the formula

wherein W is a group of the formula —O—Z—O—, the divalent bonds of the —O— or the —O—Z—O— group are in the 3,3′, 3,4′, 4,3′, or the 4,4′ positions, and Z is of the formula

wherein Q is 2,2-propylene.

11. The composition of claim 1 , further comprising 0.01 to 5 parts of an aromatic sulfonate salt based on 100 parts by weight of the total weight of the polymers in the composition, wherein a molded sample of the composition having a thickness of 2.0 mm has a UL94 flammability rating of V0.

12. The composition of claim 11 , wherein the aromatic sulfonate salt is potassium diphenyl sulfone sulfonate.

13. A method of manufacture of a composition, comprising melt blending the components of the composition of claim 1 .

14. A method of forming an article, comprising injection molding, extrusion, injection blow molding, gas assist blow molding, or vacuum forming the composition of claim 1 to form the article.

15. An article comprising the composition of claim 1 .

16. A composition comprising

10 to 20 wt. % of a bisphenol A polycarbonate;

70 to 89.9 wt. % of a polysiloxane-polycarbonate comprising

bisphenol A carbonate units and

polysiloxane carbonate units derived from a dihydroxy polysiloxane of the formula

wherein R is methyl, R 6 is propylene, E has an average value of 20 to 50, M is methoxy, and n is 1; and

0.1 to 5 wt. % of a polysiloxane-polyetherimide block copolymer, comprising

more than 20 wt. %, based on the weight of the block copolymer, of polysiloxane units in the form of blocks of the formula

wherein each R 11 and R 16 are the same C 1-12 alkylene groups, R 12 to R 15 are each methyl groups, V is a polycyclic C 12-36 group, d is 1 to 20, and g is 2 to 20; and

polyetherimide blocks comprising units of the formula

wherein R 10 is propyl, and T is

wherein

a 3.2 mm thick molded sample of the composition has a haze of less than or equal to 3% and at least 85% luminous transmittance, measured in accordance with ASTM D1003-00, and

a 3.2 mm thick molded sample retains more than 50% of its initial notched Izod impact strength of 6 to 20 ft-lb/in at 23° C. after 5 days hydro-aging at 100° C., measured in accordance with ASTM D256: 2004.

17. The composition of claim 16 , further comprising

0.01 to 5 parts of an aromatic sulfonate salt based on 100 parts by weight of the total weight of the polymers in the composition;

wherein

a molded sample of the composition having a thickness of 2.0 mm has a UL94 flammability rating of V0.

18. The composition of claim 17 , wherein

V is of the formula

wherein W is a group of the formula —O—Z—O—, the divalent bonds of the —O— or the —O—Z—O— group are in the 3,3′, 3,4′, 4,3′, or the 4,4′ positions, and Z is of the formula

wherein Q is 2,2-propylene.

19. The composition of claim 18 , wherein the aromatic salt is potassium diphenyl sulfone sulfonate.