摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A plastic preform from which a plastic container is blow molded. The preform replaces a three layer preform by providing a preform which is of a five layer construction in the base forming portion thereof and wherein a secondary material which forms the core layer of the three layer preform construction is divided into an inner intermediate layer and an outer intermediate layer by a third injection of material. The third injected material is preferably the same material as the primary material which is first injected. This results in the reduction of the cost of the preform and also provides remaining in the injection nozzle a quantity of the last injected material which is the same as the first injected material for the following preform in the same preform injection mold cavity.
摘要:
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.