Published May 1995
Polyesters and copolyesters are similar in that they both have a carboxylate ester in the repeating unit and they both are alternating copolymers of a glycol and a diacid. However, copolyesters contain more than one type of diacid and/or glycol. The additional component(s) in the polymer alters the final physical, thermal, and electrical properties of the resulting copolyester. With the proper selection of the monomer, the resulting copolyester can have advantageous properties.
Copolyesters containing 1,4-cyclohexanedimethanol (CHDM) are commercially available and used in specialty packaging applications because of their superior strength and clarity. The CHDM imparts good heat stability and physical strength to the resins. This report reviews manufacturing processes, presents preliminary process designs, and estimates capital and production costs for CHDM (because they have not been covered in previous PEP reports) and four polymers containing CHDM. Specifically, we evaluate products made from the following dimethyl esters and glycols):
- CHDM and dimethyl terephthalate
- CHDM, dimethyl terephthalate (80%), and dimethyl isophthalate (20%)
- CHDM (66%), ethylene glycol (34%), and dimethyl terephthalate
- CHDM (34%), ethylene glycol (66%), and dimethyl terephthalate
The first three products are made in a single multipurpose plant.
In this report we also include separate sections on the industry status, chemistry, and blends and additives for polymers containing CHDM.
This report will be useful to resin producers interested in either producing CHDM or using it as a monomer to produce polyesters and copolyesters.