Transparent polycarbonate-polysiloxane copolymer blend, method for the preparation thereof, and article derived therefrom
View Patent ↗A composition includes a polycarbonate-polysiloxane block copolymer that has at least one polycarbonate block and at least one polysiloxane block, and a surface modifying agent that includes at least one polysiloxane segment. Increased levels of the surface modifying agent can be incorporated without compromising high transmittance and low haze. The compositions also exhibit improved hemocompatibility and are therefore useful for a variety of articles that may contact blood.
1. A composition, comprising a blend of:
a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
wherein about 60 to 100 percent of the total number of R 1 groups are substituted or unsubstituted divalent aromatic organic radicals and 0 to about 40 percent are divalent aliphatic radicals or divalent alicyclic radicals; and wherein the polysiloxane block comprises repeating units having the structure
wherein each occurrence of R 2 is independently C 1 –C 12 hydrocarbyl; and
a surface modifying agent comprising at least one polysiloxane segment wherein the surface modifying agent comprises, in addition to the at least one polysiloxane segment, at least one segment selected from polyolefins, polyesters, polyestercarbonates, polyethers, and polyarylates.
2. The composition of claim 1 , wherein the polycarbonate-polysiloxane block copolymer consists essentially of the polycarbonate blocks and the polysiloxane blocks.
3. The composition of claim 1 , wherein R 1 has the structure
-A 1 -Y 1 -A 2 -
wherein each of A 1 and A 2 is a monocyclic divalent aryl radical; and wherein Y 1 is selected from be —O—, —S—, —S(O)—, —S(O) 2 —, —C(O)—, and C 1 –C 18 hydrocarbylene.
4. The composition of claim 1 , wherein the substituted or unsubstituted divalent aromatic organic radicals comprise the residuum of 2,2-bis(4-hydroxyphenyl)propane.
5. The composition of claim 1 , wherein each occurrence of R 2 is methyl.
6. The composition of claim 1 , wherein the polysiloxane block has the structure
wherein each occurrence of R 2 is independently C 1 –C 12 hydrocarbyl; each occurrence of R 3 is independently C 6 –C 30 hydrocarbylene; x is 0 or 1; and D is about 5 to about 120.
7. The composition of claim 6 , wherein D is about 5 to about 75.
8. The composition of claim 6 , wherein D is about 10 to about 60.
9. The composition of claim 6 , wherein each occurrence of x is 0, and each occurrence of R 3 independently has the structure
wherein each occurrence of R 4 is independently halogen, C 1 –C 8 hydrocarbyl, or C 1 –C 8 hydrocarbyloxy; m is 0 to 4; and n is 2 to about 12.
10. The composition of claim 1 , wherein the polycarbonate-polysiloxane block copolymer comprises about 70 to about 99 weight percent of the polycarbonate blocks.
11. The composition of claim 1 , wherein the polycarbonate-polysiloxane block copolymer comprises about 1 to about 30 weight percent of the polysiloxane blocks.
12. The composition of claim 1 , wherein the composition comprises about 0.1 to about 30 weight percent of total polysiloxane blocks.
13. The composition of claim 1 , comprising about 1 to about 99.9 weight percent of the polycarbonate-polysiloxane block copolymer.
14. The composition of claim 1 , wherein the surface modifying agent comprises a polyester-polysiloxane block copolymer.
15. The composition of claim 1 , wherein the surface modifying agent comprises a polycaprolactone-polydimethylsiloxane-polycaprolactone triblock copolymer.
16. The composition of claim 1 , comprising about 0.1 to about 50 weight percent of the surface modifying agent.
17. The composition of claim 1 , further comprising a polymer selected from polycarbonates, polyestercarbonates, polyesters, polyarylates, and mixtures thereof.
18. The composition of claim 1 , further comprising an impact modifier.
19. The composition of claim 1 , further comprising an additive selected from fillers, reinforcing agents, thermal stabilizers, antioxidants, light stabilizers, gamma-irradiation stabilizers, plasticizers, colorants, extenders, antistatic agents, catalyst quenchers, lubricants, mold releasing agents, processing agents, blowing agents, flame retardants, anti-drip agents, and mixtures thereof.
20. The composition of claim 1 , having a percent transmission of at least 70% measured according to ASTM D1003 at a thickness of 3.2 millimeters.
21. The composition of claim 1 , having a percent haze of less than or equal to 10% measured according to ASTM D1003 at a thickness of 3.2 millimeters.
22. The composition of claim 1 , having a notched Izod impact strength of at about 500 to about 1,000 joules per meter, measured according to ASTM D256 at 23° C.
23. The composition of claim 1 , wherein human blood exposed to the composition for 30 minutes at 35° C. has a platelet retention percent, measured according to the procedure of Examples 10 and 11, that is at least 5 percent higher than the platelet retention percent of blood exposed to a composition consisting of a bisphenol A polycarbonate homopolymer having a weight average molecular weight of about 20,000 to about 30,000 atomic mass units.
24. A composition, comprising:
a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
wherein each of A 1 and A 2 is independently a monocyclic divalent aryl radical; and wherein Y 1 is selected from be —O—, —S—, —S(O)—, —S(O) 2 —, —C(O)—, and C 1 –C 18 hydrocarbylene; and wherein the polysiloxane block has the structure
wherein each occurrence of R 2 is independently C 1 –C 12 hydrocarbyl; each occurrence of R 3 is independently C 6 –C 30 hydrocarbylene; x is 0 or 1; and D is 5 to about 120;
an aromatic polycarbonate; and
a polyester-polysiloxane block copolymer.
25. The composition according to claim 24 , comprising:
about 5 to about 99 weight percent of a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
and wherein the polysiloxane block comprises repeating units having the structure
wherein D is about 5 to about 100;
about 1 to about 95 weight percent of a bisphenol A polycarbonate; and
about 0.1 to about 10 weight percent of a polycaprolactone-poly(dimethylsiloxane)-polycaprolactone triblock copolymer.
26. The composition according to claim 25 , comprising:
about 10 to about 25 weight percent of a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
and wherein the polysiloxane block comprises repeating units having the structure
wherein D is about 30 to about 70;
about 70 to about 90 weight percent of a bisphenol A polycarbonate; and
about 0.2 to about 5 weight percent of a polycaprolactone-poly(dimethylsiloxane)-polycaprolactone triblock copolymer.
27. The composition according to claim 26 , comprising:
about 15 to about 20 weight percent of a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
and wherein the polysiloxane block comprises repeating units having the structure
wherein D is about 40 to about 60;
about 75 to about 85 weight percent of a bisphenol A polycarbonate; and
about 0.5 to about 2 weight percent of a polycaprolactone-poly(dimethylsiloxane)-polycaprolactone triblock copolymer.
28. A method of preparing a thermoplastic composition, comprising:
blending a polycarbonate-polysiloxane block copolymer comprising at least one polycarbonate block and at least one polysiloxane block; wherein the polycarbonate block comprises repeating units having the structure
wherein about 60 to 100 percent of the total number of R 1 groups are substituted or unsubstituted divalent aromatic organic radicals and 0 to about 40 percent are divalent aliphatic radicals or divalent alicyclic radicals; and wherein the polysiloxane block comprises repeating units having the structure
wherein each occurrence of R 2 is independently C 1 –C 12 hydrocarbyl; and a surface modifying agent comprising at least one polysiloxane segment wherein the surface modifying agent comprises, in addition to the at least one polysiloxane segment, at least one segment selected from polyolefins, polyesters, polyestercarbonates, polyethers, and polyarylates,
to form an intimate blend.
29. An article comprising the composition of claim 1 .
30. The article of claim 29 comprising a film, sheet, molded object, membrane, or composite.
31. The article of claim 30 wherein the film, sheet, molded object or composite has at least one layer comprising the composition.
32. An article comprising the composition of claim 24 .