In the late s, researchers found a way to stretch a thin extruded sheet of PET in two directions to create PET film, which is now used extensively for video, photo and packaging films. In the early s, the technology was developed for blow-stretch molding PET into bottles. The PET bottle was patented in The safety of PET for food, beverage, pharmaceutical and medical applications has been repeatedly demonstrated through extensive studies, regulatory approvals, testing, and its widespread acceptance for more than 30 years.
S and worldwide. More than 1. In , the U. Almost 1. The U. RPET is employed for new products such as:. The use of recycled PET in place of virgin resin typically results in reduced energy consumption, lower cost, and reduced environmental impact. Post-consumer PET material is collected through curbside recycling programs, involving both single-stream and dual-stream approaches.
Additionally, other PET recycling programs are designed to divert empty PET bottles at locations of high accumulation such as at large events. Recyclable materials such as PET may be sorted from other recyclables at material recovery centers , and baled for shipment to a PET recycling facility.
As with other scrap material, focus should be on proper bale handling and storage practices to minimize product contamination. Bales are then split open, and bottles are singulated. This material may be pre-washed and labels removed, using steam and chemicals. During the pre-wash stage, any polyvinyl chloride PVC bottles sent through a hot water or hot air trommel will turn slightly brown, providing for easier identification and removal during the manual sorting stage.
The pre-wash and label removal process allows for easier identification of material using near infrared NIR sorting equipment to remove other materials. Other technologies employed include metal detectors and manual sorting belts.
Synthesis and curing characteristics. Macromol Mater Eng —6. Wastemanage 27 9 — Polym Eng Sci — Goje AS, Mishra S Chemical kinetics, simulation, and thermodynamics of glycolytic depolymerization of poly ethylene terephthalate waste with catalyst optimization for recycling of value added monomeric products.
Macromol Mater Eng — J Phys: Condens Matte 14 44 — Grzebienek K, Wesolowski J Glycolysis of PET waste and the use of glycolysis products in the synthesis of degradable co-polyesters. Fibres Textile East Eur 12 2 — J Appl Polym Sci 69 12 — Guclu G, Yalcinyuva T, Ozgumus S, Orbay M Hydrolysis of waste polyethylene terephthalate and characterization of products by differential scanning calorimetry. Thermochim Acta — Appl Catal A Gen 1—2 :1— Ikladious NE Recycling of poly terephthalate : Identification of glycolysis product.
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Ind Eng Chem Res 40 1 — Polym Degrad Stab 96 4 — Download references. You can also search for this author in PubMed Google Scholar. Correspondence to Seong Hun Kim. Reprints and Permissions. Park, S. Poly ethylene terephthalate recycling for high value added textiles. Fashion and Textiles 1, 1 Download citation. Over the past 12 months, U.
The bottom line is that PET will grow, slowly, from an overall increase in the North American population, as well as from growth in bottled water and from some conversions from glass in packaging. The North American market has been structurally long capacity exceeding domestic demand since the mids, meaning North America does not need imports to meet its demand requirements.
Oversupply meant increased competition among producers for market share, and that led to steady price erosion, which was good for PET demand but began depressing the price premium for virgin PET over recycled resin. The industry responded to margin pressure not by rationalizing surplus capacity but by consolidating ownership. Since , the number of virgin PET producers has shrunk from eight to four, but the production capacity actually has grown and is due to expand again this year with the startup of a very large PET unit in Corpus Christi, Texas.
Making matters worse, every region of the globe has overbuilt, with Asia carrying a marginally larger portion of the overburden. The world currently has about 30 percent more virgin PET capacity than demand suggests is needed.
The story that developed in an environment of oversupply and weak demand growth was one of eroding prices for virgin PET from to In response, buyers expected similar price reductions for rPET. The observations over time by IHS Markit, augmented by conversations with market participants, led us to consider the fundamental relationships between costs and prices for virgin PET resin and rPET, based on objectively identifiable markers.
The implication is that there is an approximate price at which a buyer is indifferent between purchasing rPET and virgin, considering factors such as scrap rates, equipment utilization, corporate sustainability and recycled-content goals.
In other words, there is a point at which a buyer will prefer one resin or the other and alter his or her purchase patterns. Based on analysis of the data, the critical price point appeared to be a spread of approximately 50 cents per pound between the market price for virgin PET and that of baled PET bottles, curbside.
At that point, recyclers needed to reduce their prices or risk losing volume. Since the costs are fairly fixed to clean and upgrade recycled bottles to the minimum required intrinsic viscosity IV and to meet Food and Drug Administration FDA standards for a No Objection Letter, the easiest way to retain profitability is lower raw material prices.
The raw material for the rPET industry is baled bottles, and curbside bottle pricing fell from averages in the mid cents per pound in to less than 20 cents per pound by early , a decline of more than 40 percent in a short time. The story does not end there, and only gets worse when looking at raw materials.
In Asia, companies also overinvested in capacity for purified terephthalic acid PTA in , to the extent that those units have been running at only about 75 percent of capacity.
Imports of virgin PET into the U. Finally, the unexpected collapse of global crude oil prices since , while an economic benefit in many ways, intensified the downward pressure on PET prices.
Falling crude prices steadily lowered the cash cost of production for both chemical intermediates and, in the highly charged competitive environment, those lower costs were quickly transferred downstream to PET buyers in the form of lower PET prices. Faced with falling prices for PET, the recycling market had only one source of relief to remain cost competitive, which was paying ever lower prices for recovered containers.
Over the course of and , those prices fell steadily, and by early the curbside prices for baled bottles fell below 10 cents per pound. The report, issued by the National Association for PET Container Resources in conjunction with the Association of Plastic Recyclers, further concluded that the decrease in collection volumes in appears to be the result of a drop in PET collected curbside.
At this time, the prices for recycled bottles are very close to the cost of collection and sorting, so the incentive to collect and process PET is quite low. There are still reasonable prospects for the recovery of demand for recycled PET, promoted by growing consumer preference for recycled polymer content and sustainability-driven marketing efforts, but it appears that a rebound prompted by higher virgin prices may take a year or more, at least.
The competitive pressures holding down the prices of virgin PET resin are not expected to abate rapidly, so the dynamic that encourages virgin consumption in favor of rPET will persist. Furthermore, paraxylene PX , PTA and MEG supplies will be abundant, with capacity increases expected to outpace demand over the next few years, which will tend to hold prices down.
PET operating rates and selling prices will remain suppressed by global oversupply. However, some steps still are within the grasp of the PET industry that could encourage more rapid recovery. The prime opportunity is in the potential for rationalization of older, excess capacity.
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