초록 ▼

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 p

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.

대표청구항 ▼

1. A method of copolymerising polyethylene naphthale (PEN) and polyethylene (PET) comprising: providing PEN; providing PET; reacting the PEN and PET in the presence of alkylene glycol having up to 6 carbon atoms, to amount of the alkylene glycol being at least 0.05 weight percent based on the tota

1. A method of copolymerising polyethylene naphthale (PEN) and polyethylene (PET) comprising: providing PEN; providing PET; reacting the PEN and PET in the presence of alkylene glycol having up to 6 carbon atoms, to amount of the alkylene glycol being at least 0.05 weight percent based on the total weight of the PEN and PET, to form a copolymerized PEN/PET product.