Polymers containing cyclobutanediol and 2,2-bis(hydroxymethyl)alkylcarboxylic acid

An aqueous coating composition comprising:

• (a) an aqueous polyester dispersion comprising:
• I. at least one polyester comprising
• (i) residues of at least one 2,2,4,4-tetraalkylcyclobutane-1,3-diol in an amount in the range of from about 5 to about 95 mole percent;
• (ii) residues of 2,2-bis(hydroxymethyl) dimethylolpropionic acid in an amount in the range of from about 1 to about 50 mole percent;
• (iii) optionally, residues of at least one additional polyhydroxyl component selected from the group consisting of 2,2-dimethyl-1,3-propanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2,4-trimethyl-1,3-pentanediol, hydroxypivalyl hydroxypivalate, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2,4,4-tetramethyl-1,6-hexanediol, 1,10-decanediol, 1,4-benzenedimethanol, hydrogenated bisphenol A, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, 1,1,1-trimethylol propane, 1,1,1-trimethylolethane, glycerin, pentaerythritol, erythritol, threitol, dipentaerythritol, or sorbitol, in an amount in the range of from 0 to 65 mole percent, and
• (iv) residues of at least one polycarboxylic acid and/or a derivative thereof,
• wherein the total moles of glycols in the polyester equal 100 mole %;
• and the total number of acids in the polyester equal 100 mole %;
• and
• wherein said polyester has an acid number in the range of from about 10 to about 100 mg KOH/g and a hydroxyl number in the range of from about 0.10 to about 200 mg KOH/g;
• and
• wherein said aqueous dispersion has a mean particle size of no greater than one micron;
• II. at least one neutralizing agent;
• III. water;
• and
• (b) at least one crosslinking agent.

A water dispersible polyester comprising:

• (a) residues of at least one 2,2,4,4-tetraalkylcyclobutane-1,3-diol in an amount in the range of from about 30 to about 95 mole percent;
• (b) residues of 2,2-bis(hydroxymethyl) dimethylolpropionic acid in an amount in the range of from about 5 to about 30 mole percent;
• (c) optionally, residues of at least one additional polyhydroxyl component in an amount in the range of from 0 to 65 mole percent;
• (d) residues of at least one polycarboxylic acid and/or a derivative thereof,
• wherein the total moles of glycols in the polyester equal 100 mole %;
• and the total number of acids in the polyester equal 100 mole %;
• and
• wherein said polyester has an acid number in the range of from about 10 to about 100 mg KOH/g and a hydroxyl number in the range of from about 5 to about 200 mg KOH/g.