Transparent thermoplastic compositions having high flow and ductiliy, and articles prepared therefrom
View Patent ↗Disclosed herein is a thermoplastic composition comprising a combination of: a polysiloxane-polycarbonate copolymer and a poly(aliphatic ester)-polycarbonate copolymer comprising soft block ester units of the formula (8 a ): wherein m is 4 to 18, wherein the thermoplastic composition has a melt volume rate of 14 cc/10 min to 22 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04, wherein an article molded from the thermoplastic composition and having a thickness of 3.2 mm has a percent transmittance of greater than 85% according to ASTM D1003-00, and wherein 100% of a set of five test articles each having a thickness of 3.2 mm and molded from the thermoplastic composition exhibit ductile fracture at −40° C. when measured for notched Izod Impact according to ASTM D256-04. An article comprising the thermoplastic composition is also disclosed.
1. A thermoplastic composition comprising a combination of:
a) a polysiloxane-polycarbonate copolymer, and
b) a poly(aliphatic ester)-polycarbonate copolymer comprising soft block ester units of the formula (8a)
wherein m is 4 to 18,
wherein the thermoplastic composition has a melt volume rate of 14 cc/10 min to 22 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04,
wherein an article molded from the thermoplastic composition and having a thickness of 3.2 mm has a percent transmittance of greater than 85% according to ASTM D1003-00, and
wherein 100% of a set of five test articles each having a thickness of 3.2 mm and molded from the thermoplastic composition exhibit ductile fracture at −40° C. when measured for notched Izod Impact according to ASTM D256-04.
2. The thermoplastic composition of claim 1 comprising 55 to 90 wt % polysiloxane-polycarbonate, based on the total weight of polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
3. The thermoplastic composition of claim 1 wherein the polysiloxane-polycarbonate comprises polydiorganosiloxane blocks having repeating siloxane units of the formula (10):
wherein each occurrence of R is same or different, and is a C 1-13 monovalent organic radical, and D has an average value of 30 to 60.
4. The thermoplastic composition of claim 3 , wherein the polydiorganosiloxane blocks comprise units of formula (13):
wherein each occurrence of R is same or different, and is a C 1-13 monovalent organic radical, and D has an average value of 30 to 60, and each occurrence of R 4 is independently a divalent C 1 -C 30 aralkylene.
5. The thermoplastic composition of claim 4 , wherein the polydiorganosiloxane blocks comprise units of formula (14):
wherein each R is the same or different, and is methyl or phenyl, D has an average value of 30 to 60, each R 5 is independently a divalent C 2 -C 8 aliphatic group, each M is the same or different, and is C 1-8 alkyl or C 1-8 alkoxy, and each n is independently 0, 1, 2, 3, or 4.
6. The thermoplastic composition of claim 5 , wherein D has an average value of 40 to 60.
7. The thermoplastic composition of claim 1 , wherein the polysiloxane-polycarbonate comprises 1 to 6 wt % siloxane units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
8. The thermoplastic composition of claim 1 , wherein the polysiloxane-polycarbonate has an melt volume rate of 5 cc/10 min to 15 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04.
9. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises 3 to 4 wt % siloxane units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
10. The thermoplastic composition of claim 1 comprising 10 to 45 wt % poly(aliphatic ester)-polycarbonate, based on the total weight of polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
11. The thermoplastic composition of claim 1 , wherein the soft block ester has a glass transition temperature of 128 to 139° C.
12. The thermoplastic composition of claim 1 , wherein in the soft block ester units of formula (8a), m is 8 to 10.
13. The thermoplastic composition of claim 1 , wherein the poly(aliphatic ester)-polycarbonate has an melt volume rate of 35 cc/10 min to 45 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04.
14. The thermoplastic composition of claim 1 , wherein the poly(aliphatic ester)-polycarbonate has a melt volume rate of 35 cc/10 min to 40 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04.
15. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises 2 to 9 wt % soft block ester units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
16. The thermoplastic composition of claim 1 having a glass transition temperature of 135 to 150° C.
17. The thermoplastic composition of claim 1 having a glass transition temperature of 143 to 147° C.
18. The thermoplastic composition of claim 1 , further comprising less than or equal to 10 wt % of a polycarbonate homopolymer, based on the total weight of polysiloxane-polycarbonate, poly(aliphatic ester)-polycarbonate, and polycarbonate.
19. The thermoplastic composition of claim 18 , wherein the polycarbonate homopolymer is bisphenol A polycarbonate.
20. The thermoplastic composition of claim 16 , wherein the polycarbonate has a melt volume rate of 5 cc/10 min to 35 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04.
21. A molded article comprising the thermoplastic composition of claim 1 , wherein the molded article is a component of a portable electronic device, a computer, a medical device, an ophthalmic lens, or a glazing for automotive, building, or construction applications or is an in-mold decorated article.
22. A thermoplastic composition comprising a combination of:
a) a polysiloxane-polycarbonate copolymer, and
b) a poly(aliphatic ester)-polycarbonate copolymer comprising soft block ester units of the formula (8a)
wherein m is 4 to 18,
wherein the thermoplastic composition has a melt volume rate of 14 to 26 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04,
wherein an article molded from the thermoplastic composition and having a thickness of 3.2 mm has a percent transmittance of greater than 85% according to ASTM D1003-00, and
wherein 100% of a set of five test articles each having a thickness of 3.2 mm and molded from the thermoplastic composition exhibit ductile fracture at −30° C. when measured for notched Izod Impact according to ASTM D256-04.
23. The thermoplastic composition of claim 22 comprising 35 to 90 wt % polysiloxane-polycarbonate and 10 to 65 wt % poly(aliphatic ester)-polycarbonate, based on the total weight of polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
24. The thermoplastic composition of claim 22 , wherein the thermoplastic composition comprises 3 to 4 wt % siloxane units and 3 to 8 wt % soft block ester units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate.
25. An article comprising a thermoplastic composition comprising:
a) a polysiloxane-polycarbonate, and
b) a poly(aliphatic ester)-polycarbonate comprising soft block ester units of the formula (8a)
wherein m is 8 to 10,
wherein the thermoplastic composition comprises 1 to 6 wt % siloxane units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate and has a glass transition temperature of 143 to 147° C.,
wherein the thermoplastic composition has a melt volume rate of 14 cc/10 min to 22 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04,
wherein an article molded from the thermoplastic composition and having a thickness of 3.2 mm has a percent transmittance of greater than 85% according to ASTM D1003-00, and
wherein 100% of a set of five test articles each having a thickness of 3.2 mm and molded from the thermoplastic composition exhibit ductile fracture at −40° C. when measured for notched Izod Impact according to ASTM D256-04.
26. An article comprising a thermoplastic composition comprising:
a) 55 to 90 wt % of a polysiloxane-polycarbonate, and
b) 10 to 45 wt % of a poly(aliphatic ester)-polycarbonate comprising soft block ester units of the formula (8a)
wherein m is 8 to 10,
wherein the percentages of polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate are each based on the total weight of polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate,
wherein the thermoplastic composition comprises 1 to 6 wt % siloxane units, based on the total weight of the polysiloxane-polycarbonate and poly(aliphatic ester)-polycarbonate and has a glass transition temperature of 143 to 147° C.,
wherein the thermoplastic composition has a melt volume rate of 14 cc/10 min to 22 cc/10 min at 300° C. and under a load of 1.2 Kg and a dwell time of 6 minutes, according to ASTM D1238-04,
wherein an article molded from the thermoplastic composition and having a thickness of 3.2 mm has a percent transmittance of greater than 85% according to ASTM D1003-00, and
wherein 100% of a set of five test articles each having a thickness of 3.2 mm and molded from the thermoplastic composition exhibit ductile fracture at −40° C. when measured for notched Izod Impact according to ASTM D256-04.