Miscible polyester blends utilizing recycled polyesters
Polyester blends containing recycled, post-consumer polyethylene terephthalate are described. The blends have the advantage of being miscible (visually clear) and remaining clear after post-extrusion heat histories.
1. A miscible ternary polyester blend comprising:
(a) a post-consumer recycled polyethylene terephthalate (RPET):
(b) a 31 mole % cyclohexanedimethanol-modified polyethylene terephthalate copolyester (PETG); and either
(c1) a 50 mole % cyclohexanedimethanol-modified polyethylene terephthalate copolyester (PCTG(50)); or
(c2) a 62 mole % cyclohexanedimethanol-modified polyethylene terephthalate copolyester (PCTG(62)).
2. The blend according to claim 1 , wherein the RPET, PETG, and PCT(50) or PCTG(62) are present in an amount such that the blend is miscible and the total amount of cyclohexanedimethanol residues in the blend ranges from 18 to 45 mole percent, based on the total molar amount of diol residues in the blend.
3. The blend according to claim 1 , wherein the RPET, PETG, and PCT(50) or PCTG(62) are present in an amount such that the blend is miscible and the total amount of cyclohexanedimethanol residues in the blend ranges from 18 to 37 mole percent, based on the total molar amount of diol residues in the blend.
4. The blend according to claim 1 , which comprises PCTG(62).
5. The blend according to claim 4 , which comprises 10 to 50 weight % of RPET and 30 to 90 weight % of PETG.
6. The blend according to claim 4 , which comprises 20 to 50 weight % of RPET and 40 to 80 weight % of PETG.
7. The blend according to claim 1 , comprises PCTG(50).
8. The blend according to claim 7 , which comprises 10 to 60 weight % of RPET and 10 to 90 weight % of PETG.
9. The blend according to claim 7 , which comprises 20 to 60 weight % of RPET and 10 to 80 weight % of PETG.
10. A film, sheet, or molded article made from the polyester blend according to claim 1 .
11. A film, sheet, or molded article made from the polyester blend according to claim 2 .
12. A film sheet, or molded article made from the polyester blend according to claim 4 .
13. A film, sheet, or molded article made from the polyester blend according to claim 7 .
14. A laminate comprising at least one layer of a decorative material and at least one layer made from the polyester blend according to claim 1 .
15. A laminate comprising at least one layer of a decorative material and at least one layer made from the polyester blend according to claim 2 .
16. A laminate comprising at least one layer of a decorative material and at least one layer made from the polyester blend according to claim 4 .
17. A laminate comprising at least one layer of a decorative material and at least one layer made from the polyester blend according to claim 7 .
18. The blend according to claim 1 , which remains clear after spending a minimum of 15 minutes at a temperature of at least 110° C.
19. The blend according to claim 2 , which remains clear after spending a minimum of 15 minutes at a temperature of at least 110° C.
20. The blend according to claim 4 , which remains clear after spending a minimum of 15 minutes at a temperature of at least 110° C.
21. The blend according to claim 7 , which remains clear after spending a minimum of 15 minutes at a temperature of at least 110° C.