FORT LAUDERDALE, FLA. - Increas-ing interest in polyethylene naphthalate as a packaging material also has stimulated interest in exactly how the resin, which has seen very limited use so far, will be classified by the recycling industry. When the Food and Drug Administration this month gave its approval for PEN homopolymer use in food packaging, resin supplier Eastman Chemical Co. said PEN containers would likely carry the No. 7 ``other'' resin code, instead of the No. 1 for its commonly recycled polyester cousin, PET.
``We think PEN will recycle,'' James Caldwell, business market manager for Eastman's PEN, said at the Bev-Pak '96 conference, held April 15-17 in Fort Lauderdale. ``It may have a `7' designation, but, because it will be relatively expensive, recyclers will be only too happy to separate and recycle it.''
He noted that PEN glows strongly under black light, and thus would be easy for material recovery facility workers to separate from a mixed waste stream.
``Besides that, if you tell a [materials recovery facility] operator that he might get as much as 75 cents per pound for the PEN they separate, they would dance in the streets to get it.''
Paul Schiller, manager of marketing and sales for fine acids for Amoco Chemical Co., which is the only supplier of the primary monomer for PEN, said his view is that PEN could be classified as a polyester. Amoco prices the monomer, produced at its De-catur, Ala., plant, at $1.50 per pound, which has led to speculation that the homopolymer or copolymer PEN price could exceed $5 per pound initially.
``It is a cousin to PET, and we feel the regulations might allow it to carry the `1' designation that PET does,'' he said. ``We think that the FDA regulation only says that the product must be designated as PEN and different from other resins, but not that it had to have the strict ``7'' label.''
Jack LaCovey, a spokesman for the Society of the Plastics Indus-try Inc., which developed the recycling codes, speculated to Plastics News that PEN containers might not carry any of the SPI symbols, and that container makers might not need to identify it, except as PEN. He said the designation would be determined by manufacturers, and that SPI does not police the categorization, but only its use for identification.
Whatever the designation, Caldwell said there is already interest in PEN in recycled form, primarily because of its high cost.
``We already have people interested in recycled PEN, who figure they may get a price break by using it. For them it may be too expensive to use virgin in their application, but recycled, or blended, it might not be,'' he said.
PEN has been identified as a possible replacement for PET in hot-fill food packaging, and as a candidate to achieve the elusive goal of making a commercially viable plastic container for beer.
Though the resin is expensive, packagers see a variety of uses and speculate that copolymers and blends could reduce the overall costs of making packages from PEN. If more containers and packages are made of PEN for consumer products, the used packages will eventually wind up in the waste stream, raising questions of how they will be handled by the recycling and waste collection infrastructure.