1,3-Benzenedicarboxylic acid polymer with 1,4-benzenedicarboxylic acid, 2,2-bis(hydroxymethyl)butanoic acid, 1,4-butanediol, 1,3-di hydro-1,3-dioxo-5-isobenzofurancarboxylic acid, 1,6-diisocyanato hexane, hexanedioic acid and 2-methyl-1,3-propanediol