Polyester compositions which comprise spiro-glycol, cyclohexanedimethanol, and terephthalic acid

A process for preparing a polyester comprising the steps of:

• (I) heating a mixture comprising the monomers in the presence of a catalyst at a temperature of 150 to 240° C. for a time sufficient to produce an initial polyester, wherein said mixture comprises:
• (a) a dicarboxylic acid component comprising:
• (i) about 80 to about 100 mole % of terephthalic acid residues;
• (ii) about 0 to about 20 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms;
• and
• (b) a glycol component comprising:
• (i) about 1 to about 49 mole % spiro-glycol residues;
• and
• (ii) about 51 to about 99 mole % of at least one glycol chosen from at least one of 1,4-cyclohexanedimethanol residues and 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues;
• wherein the total mole % of the dicarboxylic acid component is 100 mole %,
• wherein the total mole % of the glycol component is 100 mole %;
• (II) heating the initial polyester of step (I) at a temperature of 240 to 320° C. for 1 to 4 hours;
• and
• (III) removing any unreacted glycols;
• wherein during said process, the molecular weight distributions of the polyester is less than 2.5.

A process for preparing a polyester comprising the steps of:

• (I) heating a mixture of monomers in the presence of a catalyst at a temperature of 150 to 240° C. for a time sufficient to produce an initial polyester, wherein said monomers comprise at least one terephthalic acid and/or esters thereof, at least on glycol comprising 1,4-cyclohexanedimethanol and/or 2,2,4,4-tetramethyl-1,3-cyclobutanediol, and at least one spiro-glycol, wherein said initial polyester comprises:
• (a) a dicarboxylic acid component comprising:
• (i) about 80 to about 100 mole % of terephthalic acid residues;
• (ii) about 0 to about 20 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms;
• and
• (b) a glycol component comprising:
• (i) about 1 to about 49 mole % of spiro-glycol residues;
• and
• (ii) about 51 to about 99 mole % of 1,4-cyclohexanedimethanol residues, 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues, or a combinations thereof;
• wherein the total mole % of the dicarboxylic acid component is 100 mole %, wherein the total mole % of the glycol component is 100 mole %;
• (II) heating the initial polyester of step (I) at a temperature of 240 to 320° C. for 1 to 4 hours to produce said polyester;
• and
• (III) removing any unreacted glycols.

A polyester composition comprising at least one polyester which comprises:

• (a) a dicarboxylic acid component comprising:
• (i) 80 to 100 mole % of terephthalic acid residues;
• (ii) 0 to 20 mole % of aromatic and/or aliphatic dicarboxylic acid residues having up to 20 carbon atoms;
• and
• (b) a glycol component comprising:
• (i) 1 to 49 mole % of spiro-glycol residues;
• and
• (ii) 51 to 99 mole % of 1,4-cyclohexanedimethanol residues and 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues;
• wherein the total mole % of the dicarboxylic acid component is 100 mole %, and
• wherein the total mole % of the glycol component is 100 mole %.