Copolyesters and blends with improved recyclability, processes for their manufacture, and articles prepared therefrom

1. An extrusion blow molded article comprising at least one polyester which comprises:

(a) a dicarboxylic acid component comprising:

(i) about 90 to about 100 mole % of terephthalic acid residues;

(ii) about 0 to about 10 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and

(b) a glycol component consisting essentially of:

(i) 45 to 55 mole % ethylene glycol residues; and

(ii) 45 to 55 mole % residues of 1,4-cyclohexanedimethanol; and

(iii) about 2 mole % or less of diethylene glycol;

(c) at least one branching agent in the amount of 0.01 to 1.0 mole %;

wherein the total mole % of the dicarboxylic acid component is 100 mole %, and

wherein the total mole % of the glycol component is 100 mole %; and

wherein the inherent viscosity of the polyester is from 0.50 to 1.0 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.; wherein said at least one polyester has a crystallization half-time from the glass phase of less than 500 minutes when measured at 160° C.; and wherein from about 0.1 to about 6.0 weight % of said at least one polyester can be blended with ISBM PET to produce a second article having a haze value of less than 3%, when measured on a film 16 mils thick, as measured by ASTM D1003, Method A.

2. The article of claim 1 wherein the branching agent is present in the amount of 0.1 to 0.6 weight % based on the total weight of the polyester.

3. The article of claim 1 wherein the branching agent is chosen from at least one of the following trimellitic acid, trimellitic anhydride, trimethylolpropane, pentaerythritol, and/or trimethylolethane.

4. The article of claim 1 wherein the inherent viscosity of the polyester is from 0.5 to 0.9 dL/g.

5. The article of claim 1 wherein the inherent viscosity of the polyester is from 0.65 to 0.8 dL/g.

6. The article of claim 1 wherein the inherent viscosity of the polyester is from 0.70 to 0.80 dL/g.

7. The article of claim 1 wherein the Tg of the polyester is from 75 to 95° C.

8. The article of claim 1 comprises at least one additive chosen from colorants, mold release agents, phosphorus compounds, plasticizers, nucleating agents, UV stabilizers, glass fiber, carbon fiber, fillers, impact modifiers, or a mixture thereof.

9. The article of claim 1 which comprises a container.

10. The article of claim 1 which comprises a bottle.

11. An extrusion blow molded article comprising a blend comprising:

(1) from 0.1 weight % to less than 6.0 weight % of at least one polyester which comprises:

(a) a dicarboxylic acid component comprising:

(i) about 90 to about 100 mole % of terephthalic acid residues;

(ii) about 0 to about 10 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and

(b) a glycol component consisting essentially of:

(i) 45 to 55 mole % ethylene glycol residues; and

(ii) 45 to 55 mole % residues of 1,4-cyclohexanedimethanol; and

(iii) about 2 mole % or less of diethylene glycol;

(c) at least one branching agent in the amount of 0.01 to 1.0 mole %;

wherein the total mole % of the dicarboxylic acid component is 100 mole %, and

(2) from 94 wt % to 99.1 wt % of ISBM PET,

wherein the total mole % of the dicarboxylic acid component is 100 mole %,

wherein the total mole % of the glycol component is 100 mole %;

wherein the inherent viscosity of the polyester is from 0.50 to 1.0 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.; wherein said at least one polyester has a crystallization half-time from the glass phase of less than 500 minutes when measured at 160° C.; and wherein said blend has a haze value of less than 3%, when measured on a film 16 mils thick, as measured by ASTM D1003, Method A.

12. An extrusion blow molded article comprising a blend comprising:

(1) from 0.1 weight % to less than 6.0 weight % of at least one polyester which comprises:

(a) a dicarboxylic acid component comprising:

(i) about 95 to about 100 mole % of terephthalic acid residues;

(ii) about 0 to about 10 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and

(b) a glycol component consisting essentially of:

(i) 45 to 55 mole % ethylene glycol residues; and

(ii) 45 to 55 mole % residues of 1,4-cyclohexanedimethanol; and

(iii) about 2 mole % or less of diethylene glycol;

(c) at least one branching agent in the amount of 0.01 to 1.0 mole %;

wherein the total mole % of the dicarboxylic acid component is 100 mole %, and

(2) from 94 wt % to 99.1 wt % of ISBM PET,

wherein the total mole % of the dicarboxylic acid component is 100 mole %,

wherein the total mole % of the glycol component is 100 mole %;

wherein the inherent viscosity of the polyester is from 0.50 to 1.0 dL/g as determined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentration of 0.25 g/50 ml at 25° C.; wherein said at least one polyester has a crystallization half-time from the glass phase of less than 500 minutes when measured at 160° C.; and wherein said blend has a haze value of less than 3%, when measured on a film 16 mils thick, as measured by ASTM D1003, Method A.