KINGSPORT, TENN. - Eastman Chemical Co. is promoting an old-fashioned symbol as the identifying mark for a new family of promising polymers. At the Kingsport-based resin maker's headquarters recently, Noel Malone, manager of plastic recycling, container plastics, and polyethylene naphthalate, said the company will lobby to use the image of an old-fashioned feather quill on containers made from PEN.
The company received Food and Drug Administration ap-proval for use of PEN homopolymer in direct food contact in April, and is boosting production of the hitherto rare polymer. Eastman, the largest producer of PET in the world, has been spearheading development of PEN as an alternative to traditional and heat-set PET in some container applications.
Production of PEN was impeded until March by the lack of availability of one of its component esters, naphthalate dicarboxylate. Early this year, however, Amoco Chemical Co. an-nounced it was starting full-scale commercial production of NDC at a new facility in Decatur, Ala.
Eastman is adding capacity to produce 20 million pounds of PEN annually, by adapting one of its current PET manufacturing lines at Kingsport. The firm hopes to have the line producing PEN by the fourth quarter of this year.
``We are being very cautious about this, and want everyone to understand that this is a specialty resin,'' Malone said. ``Some studies indicate that production of PEN will be 132 million pounds per year by the year 2005, but this is not a replacement for more widely used resin.''
Malone would not comment on the accuracy of the projections.
PEN has better barrier and heat-resistant qualities than PET, and Eastman and other companies believe it will find a niche in some hot-fill packaging applications, and perhaps beer containers. Because production of the polymer has been so limited, however, prices have been prohibitively high for mass packaging applications.
Because the proposed use of PEN in containers has been limited to regional applications outside North America, it does not have a recognized identity under the Society of the Plastics Indus-try Inc.'s resin identification code, which is required in 38 states. Without the quill symbol, PEN bottles might carry either a No. 1 symbol, like its sister resin PET, or a No. 7, for the catch-all ``other'' category.
``We would hope for some sort of consensus this fall as to what symbol we would use for PEN,'' Malone said.
``The material is not covered by the SPI code, and we feel it is important to identify PEN distinct from other polyesters,'' he said.
The importance of identifying the resin is amplified by its $4.50 per-pound cost, and the fact that producers and recyclers alike would be interested in separating it from the waste stream for recycling.
John Matthews, recycling director for Garten Foundation, a Salem, Ore., materials recovery operation that sorts and bales plastics, paper and other recyclables, said the quill identifying mark would be effective in recycling the PEN products only if there is a significant amount of it in the waste stream.
``There would have to be enough of it in the stream to make it worth sorting out,'' he said in a telephone interview. ``If not, even if it was considerably more valuable, we would not see it as a benefit.''
Because Garten has an ad-vanced optical bottle sorting machine that separates HDPE, PET and other bottles automatically, the resin also would have to be distinguishable to the machine.
``If we had to do a manual sort, as we sometimes do, the sorting personnel doesn't have time to look for the `1' or a quill. They just get to know what containers are what resin, and unless PEN was unique, or only in unique applications, then it would be difficult to separate from the other clear resins like PET and PVC.''
Malone said developing a commercially viable plastic container for beer packaging has been the holy grail of packaging, and Eastman is convinced it can be done, perhaps using a blend of PEN and its proprietary glycol-modified PET.
``We feel that 8 percent to 10 percent PEN content would be enough to give a bottle the necessary hot-fill and barrier properties, and we are working with manufacturers on the idea.''
He said the quill symbol could be used to distinguish PEN in containers, as well as films for electronics and medical packaging.