Polyethylene Terephthalate (PET) is one of the most widely used plastics globally, identified by the resin code “1” inside the chasing arrows symbol. This material is highly valued in the recycling industry, making it one of the most frequently and successfully recycled plastic polymers. The number one code signals to consumers and Material Recovery Facilities (MRFs) that it can be processed through existing mechanical recycling infrastructure. The process depends heavily on consumer participation to maintain a clean stream of material. Confirming that a container is PET #1 ensures it contributes to a circular economy.
Identifying PET #1 Plastic
PET is a polymer known for its unique strength and clarity. Its chemical structure results in a plastic that is naturally transparent, lightweight, and shatterproof, with excellent barrier properties against gases and moisture. These features make it the material of choice for packaging products requiring a long shelf life and visible contents. The #1 resin identification code categorizes the seven main types of plastic and acts as a universal language for recyclers.
Common household items made from this polymer include virtually all single-serve beverage bottles, such as those for water, soda, and juice. PET is also used to create clam-shell containers for fresh produce, peanut butter jars, and other clear food packaging. Although technically Polyethylene Terephthalate, it is often labeled as PET or PETE. The high demand for recycled PET, or rPET, drives the economic viability of its collection and reprocessing.
How PET #1 Is Mechanically Recycled
Mechanical recycling begins when collected material arrives at a Material Recovery Facility (MRF) and is compressed into dense blocks called bales. These bales are broken apart and fed onto conveyor belts where automated steps separate the PET from other materials. Advanced Near-Infrared (NIR) optical sorters identify the chemical signature of the PET polymer using light sensors. This triggers air jets to separate the desired plastic from contaminants like paper, metals, and other plastic types.
The sorted PET containers are then thoroughly washed in a hot water bath to remove residual sugar, oils, and adhesives from labels. During this specific gravity separation process, PET plastic naturally sinks because it is denser than water. Lighter materials, such as caps (often polypropylene or HDPE) and residual labels, float to the surface for easy removal. The cleaned PET containers are then shredded into small, uniform pieces known as “flake.”
These clean flakes are the immediate product of the mechanical process and are often sorted again by color before final reprocessing. The flakes are melted down and pushed through an extruder, which filters out any remaining fine impurities through a screen. The molten plastic is then cut into uniform pellets, creating the final recycled PET (rPET) resin. For rPET intended for new food-contact packaging, these pellets undergo an additional decontamination step, such as Solid-State Polycondensation (SSP), to meet food-grade purity standards.
Preparing PET #1 for Collection
Consumer preparation is a determining factor in whether a PET container successfully enters the recycling stream or ends up as a contaminant. The most important step is to empty all liquid and thoroughly rinse any food residue from the container. Contamination from food or liquid can spoil an entire batch of otherwise recyclable material, making the collection economically unviable to process.
A common point of confusion involves the bottle’s cap, which is typically made from a different type of plastic. Industry practice recommends leaving the cap screwed back onto the bottle after rinsing. This ensures the cap is captured with the PET bottle, since small, loose caps often fall through sorting screens and are lost. During processing, the PET body sinks in the wash tanks while the lighter cap material is separated and recovered for its own recycling stream.
Another important consideration is whether to crush the bottle to save space in the home recycling bin. In many single-stream systems, crushing the bottle is discouraged because automated optical sorters rely on the container’s three-dimensional shape to correctly identify it. Keeping the bottle whole allows the machinery to easily recognize it as a 3D plastic object, ensuring it is directed into the correct recycling path.
Products Created from Recycled PET
The resulting rPET pellets are a versatile raw material used to manufacture a wide array of new products, creating a closed-loop system. The most direct application is “bottle-to-bottle” recycling, where rPET is used to create new beverage containers, often incorporating a mix of virgin and recycled material. This application requires the highest purity levels and advanced decontamination achieved through processes like SSP.
Recycled PET is also used in fiber applications, where the material is spun into polyester fibers. These fibers are incorporated into textiles for clothing, such as fleece jackets and athletic wear, and are used extensively in home furnishings. Beyond fabrics, the recycled plastic is used to produce a variety of other items:
- Strapping for packaging
- Thermoformed sheets for food trays
- Automotive components, including car interior fabrics
- Carpets and upholstery
- Filling for sleeping bags and pillows