Isosorbide-based polycarbonates, method of making, and articles formed therefrom

1. A polycarbonate polymer comprising: an isosorbide unit and an aliphatic unit different from the isosorbide unit, wherein the isosorbide unit and aliphatic unit are each carbonate, or a combination of carbonate and ester units and the aliphatic unit is derived from an aliphatic oligomer having a weight average molecular weight of 900 to 4000, wherein the polycarbonate polymer has a glass transition temperature of 142 to 170° C.

2. The polycarbonate polymer of claim 1 , wherein the isosorbide units are present in an amount of 50 to 92 weight percent based on the total weight of diol and diacid used to make the polycarbonate.

3. The polycarbonate of a claim 1 , wherein the aliphatic oligomer has a weight average molecular weight of 900 to 3000.

4. The polycarbonate of claim 1 , wherein the aliphatic oligomer has a weight average molecular weight of 900 to 2500.

5. The polycarbonate of claim 1 , wherein the aliphatic units derived from an aliphatic oligomer are present in an amount of 5 to 35 wt % based on the total weight of diol and diacid used to make the polycarbonate.

6. The polycarbonate of claim 1 , wherein the aliphatic units derived from an aliphatic oligomer having the formula X-L-X wherein X represents a carboxylic acid (—C(O)OH) or a methylol group (CH 2 —OH) and L represents a group having greater than or equal to 60 carbon atoms.

7. The polycarbonate of claim 1 , further comprising a carbonate unit derived from an aromatic dihydroxy compound.

8. The polycarbonate of claim 1 , wherein the polycarbonate has bio-content greater than or equal to 20 weight percent based on the total weight of the polycarbonate.

9. The polycarbonate of claim 1 , wherein the polycarbonate has a heat deflection temperature of 30 to 180° C.

10. The polycarbonate of claim 1 , wherein the polycarbonate has a notched Izod impact strength greater than or equal to 13 kilojoules per square meter (kJ/m 2 ) at 23° C.

11. The polycarbonate of claim 1 , further comprising non-isosorbide aliphatic units derived from a C 14-44 aliphatic diacid, a C 14-44 aliphatic diol or combination of these.

12. The polycarbonate of claim 1 , wherein the polycarbonate is transparent.

13. An article comprising the polycarbonate of claim 1 .

14. A polycarbonate polymer comprising: 50 to 92 weight percent of an isosorbide unit and 5 to 35 weight percent of an aliphatic unit different from the isosorbide unit, wherein the isosorbide unit and aliphatic unit are each carbonate, or a combination of carbonate and ester units, the aliphatic unit is derived from an aliphatic oligomer having a weight average molecular weight of 900 to 4000 and weight percent is based on the total weight of diol and diacid used to make the polycarbonate, wherein the polycarbonate polymer has a glass transition temperature of 142 to 170° C.

15. The polycarbonate of claim 14 , further comprising 5 to 35 weight percent of a non-isosorbide aliphatic unit derived from a C 14-44 aliphatic diacid, a C 14-44 aliphatic diol or combination of these.

16. The polycarbonate of claim 14 , further comprising a carbonate unit derived from an aromatic dihydroxy compound.

17. The polycarbonate of claim 14 , wherein the polycarbonate has bio-content greater than or equal to 20 weight percent based on the total weight of the polycarbonate.

18. The polycarbonate of claim 14 , wherein the polycarbonate has a notched Izod impact strength greater than or equal to 13 kilojoules per square meter (kJ/m 2 ) at 23° C.

19. The polycarbonate of claim 14 , wherein the polycarbonate has a heat deflection temperature of 30 to 180° C.

20. The polycarbonate of claim 1 , wherein the aliphatic units derived from the aliphatic oligomer are present in an amount of 10 to 35 wt % based on the total weight of diol and diacid used to make the polycarbonate.

21. The polycarbonate of claim 1 , wherein the polycarbonate is phase separated.