Low levels of PLA contamination make recycled PET unusable

Tim Gaffney, Product Manager Flexible Packaging Films, found this article and we found the information extremely informative.

"Less than one polylactic acid (PLA) bottle mixed with 1,000 polyethylene terephthalate (PET) bottles makes recycled PET (RPET) unsuitable for use in containers, sheet, dramatically reduces its value. Results of independent evaluation by PTI-Europe SARL, Yverdon-les-Bains, Switzerland, commissioned by Technical Committee of Petcore, Brussels, Belgium, contradicts manufacturer claims that PLA bioplastic at levels up to 0.1% would not hinder recycling or damage quality of PET reyclate. Testing shows that level of PLA affects esthetics such as color, haze of RPET bottles, sheet. In addition, presence of PLA disrupts recycling process because lower melting point causes flakes to stick to one another, to RPET, to equipment. Findings raise fears that very low levels of PLA contamination will render RPET nearly useless for anything except noncritical fiber applications, a market where demand is declining. Unfortunately, it appears current sorting technology cannot remove enough PLA bottles to prevent problems. According to Sue Ward, secretary general of Petcore, “PLA containers can be sorted manually if the label is still in place (it is brands that identify the resin in this case) or by polymer detection such as near-infrared….The efficiency of these [near-infrared] machines is in the high 90%s, [but]…even if a recycler runs three of these machines in series (best industry practice in Europe), they cannot remove 99.9% of PLA, even when set so tightly that an unacceptable quantity of good PET bottles is removed with the PLA.” As result, Petcore position statement concludes, even small market penetration of PLA threatens recycling infrastructure for PET containers in European Union where about 40 billion PET bottles (1 million metric tons) are being recycled, and continued success depends on input purity, sorting, recycling technologies, high-quality market outlets." Follow-up: At Petcore, PLA Report, +32 2 675 39 35, info@petcore.org; Link: http://www.petcore.org/; at PTI, US office, Holland, OH, +1 419-867-5400, info@plastictechnologies.com; Link: http://www.plastictechnologies.net/.