Polyethylene 2,6-naphthalate

This is a relatively new polymer that has good barrier properties and which has been used in the packaging of olive oil. It is alos ideal for making amber coloured bottles suitable for packaging drinks such as beer. It can also be used for the manaufacture of high-performance fibres that have very high modulus and better dimensional stability than polyester or polyamide. 

This polymer has been used as an additive in long chain branched polyethylene used in food packaging. 

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In the early 1990s interest developed in the packaging material polyethylene naphthalate (PEN), a close cousin of PET. PEN has thermal stability 20°C higher than PET. Kodak had samples of the material sifting in its labs from the makers Teijin in Japan, as early as the beginning of the 1970s. Teijin is still the premier producer of PEN film and plastic today, and is involved with DuPont on the film manufacturing side. 

The manufacture of polyethylene naphthalate) (PEN) is carried out using dimethyl 2,6-naphthalene dicarboxylate (NDC) and EG and is similar to the manufacture of PET from DMT. The IV after the melt is typically in the range of 0.5... 

The influence of the ratio of hydroxylic/carboxylic end groups has been studied by several research groups. In the case of PET, this varies, based on the assumed mechanism over the range of 1.5-4.5 1. For poly(butylene terephthalate) (PBT) and polyethylene naphthalate) (PEN), the optimum is indicated at 2.0 1 [19, 20]. Any deviation from this ratio affects the reaction rate. 

The above-mentioned results of the SSP of PET can be generally applied to other semicrystalline polyesters, such as poly(butylene terephthalate) (PBT), poly(tri-methylene terephthalate) PTT), polyethylene naphthalate) (PEN) or any other kind of semicrystalline co-polyester, as a result of their similar reaction behaviors. Most of the studies have been focused on PET and PBT due to their industrial importance. Meanwhile, the popularity of PEN is growing on account of the outstanding properties of this particular polymer. 

POLYETHYLENE NAPHTHALATE), COPOLYMERS AND ESTERS 10.4 COSMETIC AND PHARMACEUTICAL CONTAINERS... 

ORIENTED POLYETHYLENE NAPHTHALATE) FILMS 4.9 MEDICAL USES... 

It should be taken into account that all of the aspects described above are of a general nature and therefore more or less valid for any kind of industrially relevant polyester resin. Upon closer examination, the experiences gained with PET are particularly applicable to poly(butylene terephthalate) (PBT), poly(trimethylene terephthalate) (PTT) and polyethylene naphthalate) (PEN). These polymers have gained major industrial importance as a result of a number of different properties in comparison with PET. 

The di-aromatic 2,6 dimethylnaphthalene (26DMN) is of particular interest for the production of polyethylene naphthalate (PEN). PEN has superior oxygen barrier and temperature resistance properties relative to PET, making it a top prospect for applications in beer bottling and reusable plastic bottle applications. Because of its superior properties to neat PET (PEN can also be incorporated into PET resin) it has a good possibility of growing in demand. 

Perhaps the most exciting developments are yet to feature in fruit juice packaging. PET can be laminated with other plastics, such as nylon and ethylene vinyl alcohol (EVOH), to give extremely good barrier properties, and polyethylene naphthalate (PEN) may enable production of a plastic bottle that can be pasteurised at high temperatures. 

MC MDI MEKP MF MMA MPEG MPF NBR NDI NR OPET OPP OSA PA PAEK PAI PAN PB PBAN PBI PBN PBS PBT PC PCD PCT PCTFE PE PEC PEG PEI PEK PEN PES PET PF PFA PI PIBI PMDI PMMA PMP PO PP PPA PPC PPO PPS PPSU Methyl cellulose Methylene diphenylene diisocyanate Methyl ethyl ketone peroxide Melamine formaldehyde Methyl methacrylate Polyethylene glycol monomethyl ether Melamine-phenol-formaldehyde Nitrile butyl rubber Naphthalene diisocyanate Natural rubber Oriented polyethylene terephthalate Oriented polypropylene Olefin-modified styrene-acrylonitrile Polyamide Poly(aryl ether-ketone) Poly(amide-imide) Polyacrylonitrile Polybutylene Poly(butadiene-acrylonitrile) Polybenzimidazole Polybutylene naphthalate Poly(butadiene-styrene) Poly(butylene terephthalate) Polycarbonate Polycarbodiimide Poly(cyclohexylene-dimethylene terephthalate) Polychlorotrifluoroethylene Polyethylene Chlorinated polyethylene Poly(ethylene glycol) Poly(ether-imide) Poly(ether-ketone) Polyethylene naphthalate Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde copolymer Perfluoroalkoxy resin Polyimide Poly(isobutylene), Butyl rubber Polymeric methylene diphenylene diisocyanate Poly(methyl methacrylate) Poly(methylpentene) Polyolefins Polypropylene Polyphthalamide Chlorinated polypropylene Poly(phenylene oxide) Poly(phenylene sulfide) Poly(phenylene sulfone)... 

Polyethylene naphthalate (PEN) polyesters are made from 2,6-naphthalene dicarboxylic acid or 2,6-naphthalene dicarboxylic acid, dimethyl ester. They have higher temperature resistance than amorphous PET and are increasingly used in applications requiring heat sterilisation of the food/drink, although PEN at the moment is significantly more expensive. Table 10.5 lists commonly used substances in polyesters. 

Naphthalenedicarboxylic acid is a precursor to polyethylene naphthalate (PEN), which is used to improve the properties of polyester bottle resins (see also problem E.1.6). It can be made by the liquid phase oxidation of 2,6-dimethylnaphthalene as described in U.S. 6,114,575, assigned to BP Amoco. Estimate the cost of production for a plant that produces 250,000 metric tons per year (250 kMTA). 

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