LOW MELT VISCOSITY AMORPHOUS COPOLYESTERS WITH ENHANCED GLASS TRANSITION TEMPERATURES

摘要

The invention relates to an amorphous copolyester having a maximum melt viscosity at 1 radian/second and at about 260 to about 290°C of about 12000 poise, a glass transition temperature ranging from about 88°C to about 120°C, and an inherent viscosity of at least about 0.6 dl/g. The amorphous copolyesters comprise the reaction product of a diol component and a dicarboxylic acid component. The diol component comprises residues of from about 5.0 to about 50 mole % of 2,2'-(sulfonylbis(4,1-phenyleneoxy))-bis(ethanol) which has chemical formula (I) and from about 50 to about 95 mole % of a mixture of at least two diols selected from the group consisting of ethylene glycol, neopentyl glycol, 1,3-propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol, and mixture thereof. The dicarboxylic acid component comprises residues of terephthallic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 2,6-naphtalene dicarboxylic acid and mixtures thereof. The amorphous copolyesters according to the invention have relatively low melt viscosities and high glass transition temperatures. Because of the low melt viscosities and relatively high glass transition temperatures, copolyesters with increased IV or molecular weight can easily be obtained. The copolyesters according to the invention can be used for molded or extruded articles, sheets, and films. Accordingly, the invention also relates to molded and extruded articles, sheets, and films made from a copolyester as described above.