Continental Pet Technologies, Inc.

Graham Packaging Pet Technologies Inc.

Steven L Schmidt

Wayne N Collette

Suppayan M Krishnakumar

Amit Suresh Agrawal

Brian A Lynch

Thomas E Nahill

Keith J Barker

Ronald Adams, Sr

Ernest A Coleman

Bryan Lynch

Oxygen-scavenging polymers and packaging for holding oxygen-sensitive products. A heat treatment process has been found to significantly increase the oxygen-scavenging performance of the polymer. The enhanced scavenging polymer can be effectively incorporated into various packaging, including transparent multilayer containers for beer and juice. In one embodiment, a multilayer package made from the scavenger provides an actual reduction in oxygen content of a contents of the package, over a long period of time (e.g., 24 weeks). The package can be stored unfilled for an extended period (without significant loss of scavenging capability) and will scavenge substantially immediately upon filling with a liquid product. The package may incorporate a relatively low weight percentage of the scavenger, thus providing enhanced scavenging in a cost-effective manner.

Enhanced oxygen-scavenging polymers, and packaging made therefrom

Process for controlling the change of intrinsic viscosity and transesterification during solid stating of a polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) blend, with an effective amount of an ethylene glycol compound. The process enables the production of a copolymer based on predefined initial and final IV's and final transesterification level, by varying the solid-stating time and/or effective amount of ethylene glycol. In one embodiment, a relatively greater amount of post-consumer PET (e.g., 70%) having an IV of on the order of 0.72-0.73, is incorporated in the blend to provide a final IV on the order of 0.80-0.85, and a moderate, controlled level of transesterification; the blend is used to injection mold a sleeve layer of a preform. In another embodiment, a substantially transparent neck finish for a preform is made from a PEN/PET blend having an amount of ethylene glycol which enables substantial transesterification, without excessive increase in IV.

Process for making PEN/PET blends and transparent articles therefrom

A multilayer plastic container having enhanced strength for high temperature and pressure applications such as the pasteurization of carbonated juice drinks. The container is commercially cost-effective in comparison to prior art pasteurizable glass containers, and provides all of the advantages of plastic over glass, i.e., lightweight, shatter-resistant, etc. In a particular embodiment, the multilayer container includes inner and outer layers of a relatively high IV virgin PET, e.g., 0.85-0.90 dl/g, and a core layer of post-consumer PET having a substantially lower IV. The container has a relatively tall and slender profile, with high orientation levels in the panel and shoulder, and an oriented thick-walled base with feet. The base preferably has a high profile and angled foot pads which are allowed to move outwardly under creep. According to a method of making a multilayer preform for such container, an enhanced injection rate and mold pressure are utilized to enhance interlayer bonding and prevent separation of the layers in spite of their substantial differences in IV.

Multilayer container resistant to elevated temperatures and pressures, and method of making the same

Process for making pen/pet blends and transparent articles therefrom

The present invention relates to a process for controlling the change of intrinsic viscosity and transesterification during solid stating of a polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) blend, with an effective amount of an alkylene glycol compound. The process enables the production of a copolymer based on predefined initial and final IV's and final transesterification level, by varying the solid-stating time and/or effective amount of alkylene glycol. In one embodiment, a relatively greater amount of post-consumer PET (e.g., 70%) having an IV of on the order of 0.72-0.73, is incorporated in the blend to provide a final IV on the order of 0.80-0.85, and a moderate, controlled level of transesterification; the blend is used to injection mold a sleeve layer of a preform. In another embodiment, a substantially transparent neck finish for a preform is made from a PEN/PET blend having an amount of alkylene glycol which enables substantial transesterification, without excessive increase in IV.

A method of forming a multi-layer polyester preform and container, particularly suitable for refillable PET carbonated beverage bottles, having an interior layer of high copolymer polyester material which resists hazing in the preform injection stage, and at least one exterior layer of a polyester to achieve enhanced strain-induced crystallization in the exterior layer during blow molding. The container can withstand higher caustic wash temperatures and exhibits reduced flavor carryover from one product to another.

Method of forming multi-layer preform and container with low

A multilayer preform and container, and method of forming the same, having at least one layer including polyethylene naphthalate (PEN) to provide enhanced oxygen barrier performance and thermal stability. The PEN layer may be a homopolymer, copolymer, or blend of PEN. In a first high-PEN embodiment, the exterior layer contains on the order of 80-100% PEN and 0-20% PET by total weight of the layer, and a core layer of a non-strain hardenable polyester such as PETG. In a second low-PEN embodiment, the exterior layer includes a strain hardenable low-PEN copolymer or blend including on the order of 1-20% PEN and 80-99% PET, and the core layer is a strain-hardenable polyester such as a low-copolymer PET. In a third mid-range PEN embodiment, the exterior wall includes a substantially amorphous PEN copolymer or blend containing on the order of 20-80% PEN and 80-20% of another polyester such as PET, and a strain-hardened core layer of polyester such as a low-copolymer PET. To further enhance the oxygen barrier and thermal stability properties, the core layer may further include a copolymer or blend of PEN. Alternatively, PEN may be provided in an interior layer only.

Multilayer preform and container with polyethylene naphthalate (PEN),

A substantially transparent package or preform made of a polymer composition including an aliphatic polyketone as an oxygen scavenger having the formula ##STR1## where n is the number of repeating units and R is hydrogen, an organic side chain, or a silicon side chain. The aliphatic polyketone may be advantageously combined with other thermoplastic polymers to provide the desired injection molding and stretch blow molding characteristics for making substantially amorphous injection molded preforms and substantially transparent biaxially oriented polyester containers. A multilayer container package may be provided having a core layer of the oxygen scavenging composition, and inner and outer layers of polyethylene terephthalate (PET). The container may further include layers of a high-oxygen barrier polymer such as ethylene vinyl alcohol (EVOH). When filled with a liquid product including water, the water vapor from the product may permeate the inner and core layers to facilitate removal and consumption of entrapped oxygen by the core scavenging layer. The aliphatic polyketone provides a highly reactive oxygen scavenger which is made from low-cost monomers and which remains colorless during processing.

Transparent package with aliphatic polyketone oxygen scavenger

Process for controlling the rate of change of intrinsic viscosity and transesterification during solid stating of a polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) blend, with an effective amount of an ethylene glycol compound. The process enables the production of a copolymer based on predefined initial and final IV's and final transesterification level, by varying the solid-stating time and/or effective amount of ethylene glycol. In one embodiment, a relatively greater amount of post-consumer PET (e.g., 70%) having an IV of on the order of 0.72-0.73, is incorporated in the blend to provide a final IV on the order of 0.80-0.85, and a moderate, controlled level of transesterification; the blend is used to injection mold a sleeve layer of a preform. In another embodiment, a substantially transparent neck finish for a preform is made from a PEN/PET blend having an amount of ethylene glycol which enables substantial transesterification, without excessive increase in IV.

Multilayer container resistant to elevated temperatures and pressures,

Method of forming multilayer preform and container with low

An oxygen scavenging composition, method of making the same, and multilayer container structures thereof which enable accelerated activation of the oxygen scavenging property and/or barrier layers to prevent depletion of the oxygen scavenging property. In making a container wall, or a precursor thereof such as a preform, a base polymer is used including post-consumer polyethylene terephthalate (PC-PET) and an oxygen scavenger. A resulting multilayer package wall may include an oxygen scavenging core layer and an inner layer of a material having a high oxygen barrier condition prior to product filling, and a second lower oxygen barrier condition after product filling. The inner layer thus allows oxygen entrapped in the container during product filling to be transmitted through the inner layer and absorbed by the core oxygen scavenging layer, in order to increase the product shelf life.

Oxygen scavenging composition for multilayer preform and container

A method of forming a multi-layer polyester preform and container, particularly suitable for refillable PET carbonated beverage bottles, having an interior layer of high copolymer polyester material which resists hazing in the preform injection stage, and at least one exterior layer of a polyester to achieve enhanced strain-induced crystallization iin the exterior layer during blow molding. The container can withstand higher caustic wash temperatures and exhibits reduced flavor carryover from one product to another.

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Merrimack, NH, United States of America

Steven L Schmidt