Polyesters from terephthalic acid, 2,2,4,4-tetramethyl-1,3-cyclobutanediol and ethylene glycol

A process for producing a copolyester, comprising:

• (1) heating a mixture, comprising:
• (a) a dicarboxylic acid component, comprising:
• i) from about 80 to 100 mole % terephthalic acid or the ester thereof;
• ii) less than or equal to 20 mole % of an aromatic dicarboxylic acid having up to 20 carbon atoms or the ester thereof;
• and
• iii) less than or equal to 10 mole % of an aliphatic dicarboxylic acid or an ester thereof having up to 16 carbon atoms;
• and
• (b) a glycol component comprising:
• iv) from about 25 to 85 mole % 2,2,4,4-tetramethyl-1,3-cyclobutanediol;
• v) from about 15 to 75 mole % ethylene glycol;
• and
• vi) less than or equal to 10 mole % of a diol having 3 to 16 carbon atoms,
• wherein the total mole % of the dicarboxylic acid component is 100 mole % and the total mole % of the glycol component is 100 mole %,
• in the presence of a catalyst at a temperature of about 150.degree. C. to 220.degree. C. for a time sufficient to produce an initial copolyester;
• and
• (2) further heating the initial polyester of step (1) at about 220 to 320.degree. C. for about 1 to 2 hours.

A process for producing a copolyester comprising:

• (1) heating the following mixture in the presence of a catalyst at a temperature of about 150.degree. C. to 220.degree. C. for a time sufficient to react a significant portion of the distillable ethylene glycol,
• (a) a dicarboxylic acid component comprising about 80 to 100 mol % terephthalic acid or esters thereof, about 0 to 20 mol % other aromatic dicarboxylic acids having up to 20 carbon atoms or esters thereof, and not more than 10 mol % aliphatic dicarboxylic acids having up to 16 carbon atoms, and
• (b) a glycol component comprising about 25 to 85 mol % 2,2,4,4-tetramethyl-1,3-cyclobutanediol, about 15 to 75 mol % ethylene glycol, and about 0 to 10 mol % other glycols having 3 to 16 carbon atoms,
• wherein the total mol % of the dicarboxylic acid component is 100 mol % and the total mol % of the glycol component is 100 mol %;
• and
• (2) further heating the mixture of step (1) at about 220 to 320.degree. C. for about 1 to 2 hours;
• and
• (3) thereafter, removing any unreacted glycols.

A copolyester consisting essentially of:

• (a) a dicarboxylic acid component, comprising:
• i) from about 80 to 100 mole % terephthalic acid or the ester thereof;
• ii) from about 0 to 20 mole % of an aromatic dicarboxylic acid having up to 20 carbon atoms or the ester thereof, and
• iii) less than or equal to 10 mole % of an aliphatic dicarboxylic acid or an ester thereof having up to 16 carbon atoms;
• and
• (b) a glycol component comprising:
• iv) from about 25 to 85 mole % 2,2,4,4-tetramethyl-1,3-cyclobutanediol;
• v) from about 15 to 75 mole % ethylene glycol;
• and
• vi) less than or equal to 100 mole % of a diol having 3 to 16 carbon atoms,
• wherein the total mole % of the dicarboxylic acid component is 100 mole % and the total mole % of the glycol component is 100 mole %.

A copolyester consisting essentially of:

• (a) a dicarboxylic acid component, comprising:
• i) from about 80 to 100 mole % terephthalic acid or the ester thereof,
• ii) from about 0 to 20 mole % of an aromatic dicarboxylic acid having up to 20 carbon atoms or the ester thereof;
• and
• (b) a glycol component comprising:
• iii) from about 25 to 85 mole % 2,2,4,4-tetramethyl-1,3-cyclobutanediol;
• iv) from about 15 to 75 mole % ethylene glycol;
• and
• v) less than or equal to 10 mole % of a diol having 3 to 16 carbon atoms,
• wherein the total mole % of the dicarboxylic acid component is 100 mole % and the total mole % of the glycol component is 100 mole %.