Transparent compositions, methods for the preparation thereof, and articles derived therefrom
View Patent ↗A reaction product comprises a polyester-polycarbonate comprising a polyester unit and a polycarbonate unit, a polycarbonate polymer, and a transesterification catalyst, wherein the polyester-polycarbonate comprises greater than or equal to 75 mole % aromatic ester units, and less than 25 mole % carbonate units. The reaction product has a haze of less than 1.7%, specifically less than 1.0% as measured at a thickness of 3.2 mm according to ASTM D1003-00. A thermoplastic composition comprising the reaction product and articles formed from therefrom are disclosed. A method of forming the reaction product is also disclosed.
1. A reaction product obtained by melt blending a combination comprising:
a first polymer comprising
aromatic ester units of formula
wherein T is a divalent aromatic radical and D 1 is a divalent aromatic radical, and
carbonate units of formula
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals;
a second polymer comprising carbonate units of formula,
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals; and
a transesterification catalyst,
wherein the first polymer comprises greater than or equal to 75 mole % aromatic ester units, and less than 25 mole % carbonate units,
wherein the reaction product has a haze of less than 1.0% measured at a thickness of 3.2 mm according to ASTM D1003-00; and wherein the first and second polymers are selected such that, in the absence of the transesterification catalyst, the similarly melt blended combination has a haze of greater than 1.0% measured at a thickness of 3.2 mm according to ASTM D1003-00.
2. The reaction product of claim 1 , wherein the first polymer further comprises a second carbonate unit, and wherein the second carbonate unit is a resorcinol carbonate unit.
3. The reaction product of claim 1 , wherein T is a residue of a mixture of isophthalic acid and terephthalic acid, and wherein each D 1 is independently a resorcinol.
4. The reaction product of claim 1 , wherein the first polyester comprises greater than or equal to 80 mole % aromatic ester units, and less than 20 mole % carbonate units.
5. The reaction product of claim 1 , wherein D 2 of the second polymer is a reaction residue of bisphenol A.
6. The reaction product of claim 1 wherein the transesterification catalyst is a tetra C 1 -C 6 alkyl phosphonium hydroxide, C 1 -C 6 alkyl phosphonium phenoxide, or a combination comprising one or more of the foregoing catalysts.
7. The reaction product of claim 1 having no observable phase separated regions as determined using transmission electron microscopy at a magnification of 66,000×.
8. A method for forming a reaction product, comprising melt blending a combination comprising:
a first polymer comprising
aromatic ester units of formula
wherein T is a divalent aromatic radical and D 1 is a divalent aromatic radical, and
carbonate units of formula
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals;
a second polymer comprising carbonate units of formula,
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals; and
a transesterification catalyst,
wherein the polyester comprises greater than or equal to 75 mole % aromatic ester units, and less than 25 mole % carbonate units,
to provide the reaction product with a haze of less than 1.0%, measured at a thickness of 3.2 mm according to ASTM D1003-00; and wherein the first and second polymers are selected such that, in the absence of the transesterification catalyst, the similarly melt blended combination has a haze of greater than 1.0% measured at a thickness of 3.2 mm according to ASTM D1003-00.
9. The method of claim 8 wherein reacting is at 80 to 315° C.
10. The method of claim 8 wherein reacting is effected using a twin screw extruder.
11. The method of claim 8 wherein the transesterification catalyst is present in an amount of 40 to 220 ppm.
12. A reaction product made by the method of claim 8 .
13. A thermoplastic composition formed by the reaction product of claim 1 .
14. An article comprising the thermoplastic composition of claim 13 .
15. A thermoplastic composition comprising:
a reaction product obtained by melt blending a combination comprising:
a first polymer comprising
aromatic ester units of formula
wherein T is a divalent aromatic radical and D 1 is a divalent aromatic radical, and
carbonate units of formula
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals;
a second polymer comprising carbonate units of formula,
wherein at least 60% of the total number of D 2 groups are divalent aromatic radicals and the balance thereof are divalent aliphatic, alicyclic, or aromatic radicals; and
a transesterification catalyst,
wherein the polyester-polycarbonate comprises greater than or equal to 75 mole % aromatic ester units, and less than 25 mole % carbonate units,
to provide the reaction product with a haze of less than 1.0%, measured at a thickness of 3.2 mm according to ASTM D1003-00; and wherein the first and second polymers are selected such that, in the absence of the transesterification catalyst, the similarly melt blended combination has a haze of greater than 1.0% measured at a thickness of 3.2 mm according to ASTM D1003-00.
16. The thermoplastic composition of claim 15 , further comprising an additive selected from the group consisting of additional polymers, impact modifiers, fillers, reinforcing agents, thermal stabilizers, antioxidants, light stabilizers, gamma-irradiation stabilizers, plasticizers, colorants, antistatic agents, lubricants, mold releasing agents, flame retardants, anti-drip agents, and a combination comprising one or more of the foregoing additives.
17. The thermoplastic composition of claim 16 , wherein the additional polymers comprise polyesters, polysiloxane-polycarbonates, or a combination comprising one or more of the foregoing polymers.
18. The thermoplastic composition of claim 16 , wherein the reaction product separated from the additive has a haze of less than 1.0% at a thickness of 3.2 mm, according to ASTM D1003-00.
19. An article comprising the thermoplastic composition of claim 15 .
20. A reaction product of a combination comprising
a polyester-polycarbonate copolymer, comprising ester units of the formula:
wherein the ester units comprise a mixture of terephthalate and isophthalate having a weight ratio of 91:9 to 2:98, wherein the mole percent of r is greater than or equal to 75 mole %, the mole % of s is 1 to 25 mole %, and the mole % of t is less than 25 mole %, and the sum of r+s+t equals 100 mole %; and
a polycarbonate of the formula:
wherein the weight averaged molecular weight of the polycarbonate copolymer is 10,000 to 40,000 as determined using gel permeation chromatography; and
40 to 220 ppm of a transesterification catalyst,
wherein the reaction product has a haze of less than 1.0%, measured at a thickness of 3.2 mm according to ASTM D1003-00.