Abstract: Generation of acetaldehyde from a polyethylene terephthalate resin migrating to a vapor space between the contents of a container and the container closure may be controlled by the addition of acetaldehyde scavenging additives to the closure polymer or to a liner polymer in direct contact with the vapor space.

Abstract: Polyester compositions are disclosed that include polyester polymers or copolymers having incorporated therein particles of one or more transition metal compounds that improve the reheat properties of the compositions. The transition metal compounds are binary compounds of a transition metal element selected from titanium, vanadium, zirconium, niobium, hafnium, and tantalum, and a non-metallic element selected from boron, carbon, and nitrogen. Processes for making such polyester compositions are also disclosed. The particles may be incorporated in the polyester by melt compounding, or may be added at any stage of the polymerization, such as during the melt-phase of the polymerization. A range of particle sizes may be used, as well as a range of particle size distributions. The polyester compositions are suitable for use in packaging made from processes in which a reheat step is desirable.

Abstract: A method for incorporating a UV light absorbing compound into a polyester prepared using direct esterification of reactants selected from a dicarboxylic acid and a diol. The method comprises reacting the reactants in an esterifying reactor under conditions sufficient to form an esterified product including at least one of an ester, an oligomer, or mixture having an ester and a mixture of low molecular weight polyester; polymerizing the esterified product in a polycondensation reactor to form a polyester; and adding the UV absorbing compound to the esterified products when at least 50% of the carboxy groups initially present in the reactants have been esterified to obtain a yield of UV absorbing compound incorporated into the polyester of greater than 25%. Articles utilizing the UV protected polyester prepared by the method of the invention are additionally disclosed.

Abstract: A method for incorporating a UV light absorbing compound into a polyester prepared using direct esterification of reactants selected from a dicarboxylic acid and a diol, the method comprising reacting the reactants in an esterifying reactor under conditions sufficient to form an esterified product including at least one of an ester, an oligomer, or mixture having an ester and a mixture of low molecular weight polyester; polymerizing the esterified product in a polycondensation reactor to form a polyester; and adding the UV absorbing compound to the esterified products when at least 50% of the carboxy groups initially present in the reactants have been esterified to obtain a yield of UV absorbing compound incorporated into the polyester of greater than 40%. Articles utilizing the UV protected polyester are additionally disclosed.

Abstract: A method for incorporating a nitrogen containing methine light absorbing compound into a polyester prepared using direct esterification of reactants selected from a dicarboxylic acid and a diol, the method comprising reacting the reactants in an esterifying reactor under conditions sufficient to form an esterified product including at least one of an ester, an oligomer, or mixture having an ester and a mixture of low molecular weight polyester; polymerizing the esterified product in a polycondensation reactor to form a polyester; and adding the light absorbing compound to the esterified products when at least 50% of the carboxy groups initially present in the reactants have been esterified. Articles utilizing the light protected polyester are additionally disclosed.