Polycarbonate copolymer and associated film extrusion composition, extruded film, and capacitor

1. A polycarbonate-polysiloxane comprising, based on 100 mole percent of total carbonate units in the polycarbonate-polysiloxane,

35 to 64.95 mole percent of first carbonate units having the structure

wherein R 1 is a C 6 -C 16 divalent aromatic group;

35 to 64.95 mole percent of second carbonate units having the structure

wherein R 2 is a C 17 -C 40 divalent aromatic group having the structure

wherein R f and R g are each independently at each occurrence C 1 -C 12 alkyl, C 1 -C 12 alkoxyl, or C 2 -C 12 alkenyl; each R h is hydrogen or two occurrence of R h combine with the carbon atom to which they are attached to form a carbonyl group; each occurrence of R i is independently C 1 -C 6 alkyl; R j is hydrogen, C 1 -C 6 alkyl, or phenyl optionally substituted with 1, 2, 3, 4, or 5 C 1 -C 6 alkyl groups; R k is independently at each occurrence C 1 -C 3 alkyl or phenyl, preferably methyl; X b is C 6 -C 12 arylene, C 4 -C 18 cycloalkylene, C 4 -C 18 cycloalkylidene, or —C(R m )(R n )— wherein R m is hydrogen, C 1 -C 12 alkyl, or C 6 -C 12 aryl, and R n is C 6 -C 10 alkyl, C 6 -C 8 cycloalkyl, or C 6 -C 12 aryl, or X b is -(Q a ) x -G-(Q b ) y -, wherein Q a and Q b are each independently C 1 -C 3 alkylene, G is C 3 -C 10 cycloalkylene, x is zero or 1, and y is zero or 1; and j, m, and n are each independently zero, 1, 2, 3, or 4; and

0.05 to 0.16 mole percent of third carbonate units, each third carbonate unit comprising a divalent carbonate group and a divalent polysiloxane group, the divalent polysiloxane group comprising 5 to 60 diorganosiloxane units having the structure

wherein each occurrence of R 3 is independently a C 1 -C 13 hydrocarbyl group;

wherein the polycarbonate-polysiloxane has a weight average molecular weight of 18,000 to 35,000 grams/mole, determined by gel permeation chromatography with bisphenol A polycarbonate standards; and

wherein if the polycarbonate-polysiloxane comprises 70 to 79.95 mole percent of the second carbonate units, then the polycarbonate-polysiloxane has a weight average molecular weight of 18,000 to 24,000 grams/mole.

2. The polycarbonate-polysiloxane of claim 1 , wherein the first carbonate units have the structure

and

the second carbonate units have the structure

or a combination thereof.

3. The polycarbonate-polysiloxane of claim 1 , wherein the third carbonate units have the structure

wherein Ar is independently at each occurrence a C 6 -C 24 aromatic divalent group optionally substituted with 1, 2, 3, or 4 substituents, each substituent independently selected from the group consisting of halogen, C 1 -C 6 alkyl, and C 1 -C 6 alkoxyl; R 4 is independently at each occurrence a C 2 -C 8 divalent aliphatic group; R 5 and R 6 are independently at each occurrence C 1 -C 12 alkyl or C 6 -C 18 aryl; m and n and q are independently at each occurrence zero or 1; and p is (30-n-q) to (60-n-q).

4. The polycarbonate-polysiloxane of claim 1 , wherein

the first carbonate units have the structure

the second carbonate units have the structure

or a combination thereof;

the third carbonate units have the structure

wherein Ar is independently at each occurrence a C 6 -C 24 aromatic divalent group optionally substituted with 1, 2, 3, or 4 substituents, each substituent independently selected from the group consisting of halogen, C 1 -C 6 alkyl, and C 1 -C 6 alkoxyl; R 4 is independently at each occurrence a C 2 -C 8 divalent aliphatic group; R 5 and R 6 are independently at each occurrence C 1 -C 12 alkyl or C 6 -C 18 aryl; m and n and q are independently at each occurrence zero or 1; and p is (30-n-q) to (60-n-q); and

the polycarbonate-polysiloxane has a weight average molecular weight of 20,000 to 35,000 grams/mole, determined by gel permeation chromatography using bisphenol A polycarbonate standards.

5. A composition comprising a polycarbonate-polysiloxane comprising, based on 100 mole percent of total carbonate units in the polycarbonate-polysiloxane:

35 to 64.95 mole percent of first carbonate units having the structure

wherein R 1 is a C 6 -C 16 divalent aromatic group;

35 to 64.95 mole percent of second carbonate units having the structure

wherein R 2 is a C 17 -C 40 divalent aromatic group having the structure

wherein R f and R g are each independently at each occurrence C 1 -C 12 alkyl, C 1 -C 12 alkoxyl, or C 2 -C 12 alkenyl; each R h is hydrogen or two occurrence of R h combine with the carbon atom to which they are attached to form a carbonyl group; each occurrence of R i is independently C 1 -C 6 alkyl; R 1 is hydrogen, C 1 -C 6 alkyl, or phenyl optionally substituted with 1, 2, 3, 4, or 5 C 1 -C 6 alkyl groups; R k is independently at each occurrence C 1 -C 3 alkyl or phenyl, preferably methyl; X b is C 6 -C 12 arylene, C 4 -C 18 cycloalkylene, C 4 -C 18 cycloalkylidene, or —C(R m )(R n )— wherein R m is hydrogen, C 1 -C 12 alkyl, or C 6 -C 12 aryl, and R n is C 6 -C 10 alkyl, C 6 -C 8 cycloalkyl, or C 6 -C 12 aryl, or X b is -(Q a ) x -G-(Q b ) y -, wherein Q a and Q b are each independently C 1 -C 3 alkylene, G is C 3 -C 10 cycloalkylene, x is zero or 1, and y is zero or 1; and j, m, and n are each independently zero, 1, 2, 3, or 4; and

0.05 to 0.16 mole percent of third carbonate units, each third carbonate unit comprising a divalent carbonate group and a divalent polysiloxane group, the divalent polysiloxane group comprising 5 to 60 diorganosiloxane units having the structure

wherein each occurrence of R 3 is independently a C 1 -C 13 hydrocarbyl group;

wherein the polycarbonate-polysiloxane has a weight average molecular weight of 18,000 to 35,000 grams/mole, determined by gel permeation chromatography with bisphenol A polycarbonate standards; and

wherein if the polycarbonate-polysiloxane comprises 70 to 79.95 mole percent of the second carbonate units, then the polycarbonate-polysiloxane has a weight average molecular weight of 18,000 to 24,000 grams/mole.

6. The composition of claim 5 , comprising, based on the total weight of the composition:

70 to 99.95 weight percent of the polycarbonate-polysiloxane; and

0.05 to 2 weight percent of a roughening agent.

7. The composition of claim 6 , wherein the roughening agent comprises a particulate crosslinked polymethylsilsesquioxane having a median equivalent spherical diameter of 0.1 to 10 micrometers determined by laser diffraction according to ISO 13320:2009.

8. The composition of claim 5 , wherein

the composition comprises 70 to 99.95 weight percent of the polycarbonate-polysiloxane and further comprises 0.05 to 2 weight percent of a roughening agent;

the first carbonate units have the structure

the second carbonate units have the structure

or a combination thereof;

the third carbonate units have the structure

wherein Ar is independently at each occurrence a C 6 -C 24 aromatic divalent group optionally substituted with 1, 2, 3, or 4 substituents, each substituent independently selected from the group consisting of halogen, C 1 -C 6 alkyl, and C 1 -C 6 alkoxyl; R 4 is independently at each occurrence a C 2 -C 8 divalent aliphatic group; R 5 and R 6 are independently at each occurrence C 1 -C 12 alkyl or C 6 -Cis aryl; m and n and q are independently at each occurrence zero or 1; and p is (30-n-q) to (60-n-q);

the polycarbonate-polysiloxane has a weight average molecular weight of 20,000 to 35,000 grams/mole, determined by gel permeation chromatography using bisphenol A polycarbonate standards; and

the roughening agent comprises a particulate crosslinked polymethylsilsesquioxane having a median equivalent spherical diameter of 0.1 to 10 micrometers determined by laser diffraction according to ISO 13320:2009.

9. An extruded film comprising the composition of claim 5 .

10. The extruded film of claim 9 ,

wherein the extruded film has a thickness of 2 to 15 micrometers; and

wherein the composition comprises, based on the total weight of the composition, 70 to 99.95 weight percent of the polycarbonate-polysiloxane, and 0.05 to 2 weight percent of a roughening agent comprising a particulate crosslinked polymethylsilsesquioxane having a median equivalent spherical diameter of 0.1 to 10 micrometers determined by laser diffraction according to ISO 13320:2009.

11. A capacitor comprising:

an extruded film comprising the composition of claim 5 ; and

an electrically conductive metal layer in contact with the extruded film.

12. A metallized film comprising:

an extruded film comprising the composition of claim 5 ; and

an electrically conductive metal layer in contact with the extruded film.