2,6-dimethylnaphthalene (2,6-DMN) is a precursor to a polyester which has enhanced properties. Dimethyl naphthalene can be oxidized and esterified to give dimethyl 2,6-naphthalene dicarboxylate (NDC). This monomer undergoes polycondensation with ethylene glycol to give polyethylene naphthalate (PEN). PEN's properties offer considerable improvement over those of polyethylene terephthalate (PET). Because of the multistep processing involved in obtaining 2,6-DMN, and further processing to NDC and PEN, the PEN homopolymer is presently priced at a significant premium to PET. Attractive applications for PEN are those where its physical advantages outweigh its cost disadvantage. PEN blow-molded containers exhibit excellent properties in hot-fill food (baby food, ketchup) and drink applications, reusable packaging, and packaging of oxygen reactive goods. PEN, like PET, has good clarity. Advantages of PEN over PET are its 35°C to 55°C higher use temperature, 50 percent greater tensile strength, and fivefold better barrier performance. Additional markets for PEN encompass laminates, copolymers, and blends. However, if PEN is to penetrate large volume applications such as beer bottles and single-serve carbonated beverage bottles, then the cost of making 2,6-DMN must be reduced. A number of feedstocks and processing options have been considered in an attempt to develop an optimized scheme which will succeed in producing 2,6-DMN, and ultimately PEN, at a price which will let PEN break through into high volume markets. Some of the various options are outlined in the figure on the next page. The chemistry, process technology and comparative economics of the approaches shown for 2,6-DMN manufacture are presented in this report. 
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