TRANSPARENT ARTICLES PREPARED FROM THERMOPLASTIC COMPOSITIONS HAVING LOW BIREFRINGENCE

• US 20110071261A1
• Filed: 09/10/2010
• Published: 03/24/2011
• Est. Priority Date: 12/31/2008
• Status: Active Grant

• Current Assignee: SHPP Global Technologies BV (Government of Saudi Arabia)
• Original Assignee: Sabic Innovative Plastics IP BV (Government of Saudi Arabia)
• Inventors: Kamps, Jan Henk, Hoeks, Theodorus Lambertus, Kung, Edward, Karlik, Dennis, Takemori, Michael Teruki
• Granted Patent: US 8,064,140 B2
• Time in Patent Office: Days
• US Class Current: 525/418
• CPC Class Codes: C08G 63/64 Polyesters containing both carboxylic ester groups and carbonate groups
• CPC Class Codes: C08G 64/06 not containing aliphatic unsaturation
• CPC Class Codes: C08L 69/00 Compositions of polycarbonates; Compositions of derivatives of polycarbonates
• CPC Class Codes: G02B 1/04 made of organic materials, e.g. plastics G02B1/08 takes precedence

Abstract

An optical grade article comprises a thermoplastic composition comprising a poly(aliphatic ester)-polycarbonate copolymer comprising 10 to 25 wt % of a soft block ester unit derived from a C_20-44 aliphatic dicarboxylic acid or derivative thereof, 34 to 77 wt % of a carbonate unit derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, 0 to 76 wt % of a carbonate unit derived from a dihydroxyaromatic compound not identical to the 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, wherein the weight percentages of soft block ester units, 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine units, and dihydroxyaromatic compound units is 100 weight percent of the monomeric units of the poly(aliphatic ester)-polycarbonate, the refractive index of the thermoplastic composition is greater than 1.590, and the glass transition temperature of the poly(aliphatic ester)-polycarbonate is from 120 to 155° C. A camera lens also comprises the poly(aliphatic ester)-polycarbonate.

Claims

1. An optical grade article comprising a thermoplastic composition comprising a poly(aliphatic ester)-polycarbonate copolymer comprising the following monomeric units:

10 to 25 wt % of a soft block ester unit derived from a C_20-44 aliphatic dicarboxylic acid or derivative thereof, 34 to 77 wt % of a carbonate unit derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine,

0 to 76 wt % of a carbonate unit derived from a dihydroxyaromatic compound excluding 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, and wherein the sum of the weight percentages of soft block ester units, 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine units, and dihydroxyaromatic compound units is 100 weight percent of the monomeric units of the poly(aliphatic ester)-polycarbonate, and

wherein the refractive index of the thermoplastic composition is greater than or equal to 1.590, and the glass transition temperature of the copolymer is from 120 to 155°

C.

2. The optical grade article of claim 1, comprising the following monomeric units:

10 to 25 wt % of the soft block ester unit, and

34 to 75 wt % of the carbonate unit derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, and

0 to 58 wt % of the carbonate unit derived from a dihydroxyaromatic compound excluding 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine,

wherein the sum of the weight percentages of soft block ester units, 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine units, and dihydroxyaromatic compound units is 100 weight percent of the monomeric units of the poly(aliphatic ester)-polycarbonate.

3. The optical grade article of claim 1, the poly(aliphatic ester)-polycarbonate comprising the following monomeric units:

11 to 21 wt % of the soft block ester unit,

34 to 53 wt % of the carbonate unit derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine, and

33 to 58 wt % of the carbonate unit derived from a dihydroxyaromatic compound excluding 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine,

wherein the sum of the weight percentages of soft block ester units, 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine units, and dihydroxyaromatic compound units is 100 weight percent of the monomeric units of the poly(aliphatic ester)-polycarbonate.

4. The optical grade article of claim 1, wherein the poly(aliphatic ester)-polycarbonate copolymer has a weight average molecular weight of 10,000 to 25,000 g/mol, when measured by gel permeation chromatography using a crosslinked styrene-divinylbenzene column calibrated to polycarbonate standards.

5. The optical grade article of claim 1, wherein the thermoplastic composition has a melt volume rate of 13 to 25 cc/10 min at 250°

C. and under a load of 1.2 kg and a dwell time of 4 minutes, according to ISO 1133.

6. The optical grade article of claim 1, wherein the soft block ester units are derived from a branched aliphatic dicarboxylic acid of formula (9f):

7. The optical grade article of claim 1, wherein the C_20-44 aliphatic dicarboxylic acid comprises C₃₆ aliphatic dicarboxylic acid, C₄₄ aliphatic dicarboxylic acid, or a combination comprising at least one of the foregoing.

8. The optical grade article of claim 1, wherein the 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine has the formula (8):

9. The optical grade article of claim 8, wherein the 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine is 2-phenyl-3,3-bis(4-hydroxyphenyl)phthalimidine, having the formula (8a):

10. The optical grade article of claim 1, wherein the dihydroxyaromatic compound comprises bisphenol A, bis(3-methyl-4-hydroxyphenyl)cyclohexane, or a combination comprising at least one of the foregoing.

11. The optical grade article of claim 1, wherein the thermoplastic composition when molded into an article having a thickness of 3.2 mm, has a haze of less than or equal to 1.0 percent, when measured according to ASTM D1003-00.

12. The optical grade article of claim 1, wherein the thermoplastic composition when molded into an article having a thickness of 3.2 mm, has a transmittance of greater than or equal to 85 percent, when measured according to ASTM D1003-00.

13. The optical grade article of claim 1, wherein the thermoplastic composition, when molded into an article having a thickness of 3.2 mm, has a yellowness index (YI) of less than 4, when measured according to ASTM D1925-70.

14. The optical grade article of claim 1, wherein the birefringence of a plaque having a thickness of 1.2 mm and molded from the thermoplastic composition at a barrel temperature of 300°

C. and a mold temperature of 100°

C. has a comparative average birefringence measured by polarized light microscope using the Michel-Levy birefringence scale of less than or equal to 300 nanometers.

15. The optical grade article of claim 1, wherein the intrinsic birefringence of a film of the poly(aliphatic ester)-polycarbonate, having a thickness of 250 to 500 nm, and rubbed the point of saturation, is less than or equal to 0.015.

16. The optical grade article of claim 1, wherein the thermoplastic composition further comprises a polycarbonate.

17. The optical grade article of claim 16, wherein the thermoplastic composition comprises 50 to 99 wt % poly(aliphatic ester)-polycarbonate, and 1 to 50 wt % polycarbonate, based on the total weight of poly(aliphatic ester)-polycarbonate and any added polycarbonate.

18. The optical grade article of claim 1, wherein the optical grade article is a camera lens, goggle lens, light guide, an imaging medium, or transparent bezel.

23. An imaging apparatus comprising a light proof housing, wherein said housing contains a light transmission medium containing an optical grade article of claim 1, a shutter, a shutter control vehicle, and an imaging substrate.

19. An optical grade article comprising a thermoplastic composition comprising a poly(aliphatic ester)-polycarbonate copolymer comprising:

10 to 21 wt % of soft block ester units derived from an alpha, omega C_20-44 aliphatic dicarboxylic acid or derivative thereof,

34 to 53 wt % of a carbonate unit derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine,

34 to 58 wt % of a carbonate unit derived from a dihydroxyaromatic compound not identical to the 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine,

wherein the sum of the weight percentages of the soft block ester units, 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimidine units, and dihydroxyaromatic compound units is 100 weight percent of the monomeric units of the poly(aliphatic ester)-polycarbonate,

wherein the thermoplastic composition when molded into an article having a thickness of 3.2 mm, has a haze of less than or equal to 1.0 percent, when measured according to ASTM D1003-00,

wherein the refractive index of the thermoplastic composition at a mold temperature of 100°

C. is greater than 1.590, and the glass transition temperature of the poly(aliphatic ester)-polycarbonate is from 135 to 140°

C.

20. A camera lens comprising a thermoplastic composition comprising:

a) a poly(aliphatic ester)-polycarbonate copolymer comprising the following monomeric units;

10 to 25 wt % of soft block ester units of the formula (9e);

21. The camera lens of claim 20, having an effective lens area of 0.5 to 10 mm².

22. The camera lens of claim 20, wherein the camera lens thickness is from 0.25 to 2.5 mm.

24. A camera lens comprising a thermoplastic composition comprising:

a) a poly(aliphatic ester)-polycarbonate copolymer comprising the following monomeric units;

10 to 25 wt % of soft block ester units of the formula (9e);