Abstract: This invention relates to PET copolymer composition that have both 1,4-cyclohexanedimethal (CHDM) and isophthalic acid moieties copolymerized. These compositions have better oxygen and carbon dioxide barrier properties than either PET homopolymer or CHDM-modified PET copolymers. These copolymer compositions are useful for packaging applications (such as carbonated soft drink bottles) requiring barrier properties to oxygen and carbon dioxide at least as good or better than PET homopolymer.

Abstract: Disclosed is a select class of liquid crystalline polyesters and molding compositions comprising the polyesters and glass fiber. The liquid crystalline polyesters consist essentially of (1) diacid residues consisting essentially of (i) cyclohexanedicarboxylic acid residues and (ii) other diacid residues selected from terephthalic acid residues, 2,6-naphthalenedicarboxylic acid residues, or a mixture thereof; (2) diol residues consisting essentially of hydroquinone residues, 4,4'-biphenol residues or a mixture thereof; and, optionally, (3) p-hydroxybenzoic acid residues. In the above definition, the moles of diol residues are equal to the moles of diacid residues and the total of the (1), (2) and (3) mole percentages is equal to 100. The liquid crystalline polyesters have melting points determined by differential scanning calorimetry equal to or less than 375.degree. C.

Abstract: Disclosed is a process for the recovery of naphthalenedicarboxylic acid (NDA) from polyester materials prepared from and/or containing residues of NDA such as a poly(alkylene naphthalenedicarboxylate). In one embodiment, the process comprises contacting a polyester material prepared from and/or containing residues of NDA with water at a temperature of about 125 to 400.degree. C. in a pressured vessel to obtain an aqueous slurry of NDA and recovering the NDA. A second embodiment of the process comprises contacting such a polyester with an aqueous, alkali metal base solution to obtain an aqueous solution of a di-alkali metal naphthalenedicarboxylate salt, then neutralizing the aqueous solution with an acid to obtain an aqueous slurry or dispersion of NDA and recovering the NDA. The process is particularly useful for recovering 2,6-naphthalenedicarboxylic acid (2,6-NDA) from poly(ethylene naphthalenedicarboxylate) polyesters.

Abstract: A polyester having increased UV absorption comprising (i) a residue of a dicarboxylic acid component comprising terephthalic and from about 1 to about 20 mole % of isophthalic acid, (ii) a residue of a glycol component comprising ethylene glycol, and (iii) from about 0.01 mole % to about 15 mole % of a residue of an aromatic diol derivative, wherein the aromatic diol derivative has a least two polyester reactive groups that are capable of participating in a polyester-forming reaction and the total mole % for components (i), (ii) and (iii) is 200 mole %.

Abstract: The present invention relates to a process for minimizing the formation of undesirable byproducts in ozonated liquids comprising the steps of:providing a container comprising a polyester comprising repeat units from a dicarboxylic acid component comprising at least about 85 mole percent terephthalic acid, 2,6-naphthalenedicarboxylic acid or a mixture thereof and at least about 85 mole percent ethylene glycol; and from about--to about--weight % of at least one polyamide which displays a melting point below that of said polyester, andfilling said container with an ozonated liquid.

Abstract: Disclosed is a select class of liquid crystalline polyesters and molding compositions comprising the polyesters and glass fiber. The liquid crystalline polyesters consist essentially of (1) diacid residues consisting essentially of (i) cyclohexanedicarboxylic acid residues and (ii) other diacid residues selected from terephthalic acid residues, 2,6-naphthalene-dicarboxylic acid residues, or a mixture thereof; (2) diol residues consisting essentially of hydroquinone residues, 4,4'-biphenol residues or a mixture thereof; and, optionally, (3) p-hydroxybenzoic acid residues. In the above definition, the moles of diol residues are equal to the moles of diacid residues and the total of the (1), (2) and (3) mole percentages is equal to 100. The liquid crystalline polyesters have melting points determined by differential scanning calorimetry equal to or less than 360.degree. C.

Abstract: The present invention comprises polyester blend compositions having improved flavor retaining properties and color, comprising:(A) 98.0 to 99.95 weight percent of a polyester which comprises(1) a dicarboxylic acid component comprising repeat units from at least 85 mole percent terephthalic acid or naphthalenedicarboxylic acid derived from terephthalic acid or naphthalenedicarboxylic acid respectively; and(2) a diol component comprising repeat units from at least 85 mole percent ethylene glycol, based on 100 mole percent dicarboxylic acid and 100 mole percent diol; and(B) 2.0 to 0.05 weight percent of a polyamide; wherein the combined weights of (A) and (B) total 100 percent.