Recycled PET strap: how recycled content gets into strap, and what buyers should ask

PET strap can be made partly or wholly from recycled PET. In August 2019 there are good reasons for that fact to move from the sustainability page into the purchasing specification: governments are signalling that they intend to reward recycled content, and customers may ask for it. Before a recycled-content figure appears on a purchase order, it helps to understand how the material gets into the strap and what the figure does and does not tell you.

From used PET to strap: the route in outline

The details differ between producers, but the route usually follows these stages:

1. Collection and sorting. Post-consumer PET, much of it from drinks bottles, is collected and sorted from other plastics and materials. Pre-consumer material, such as production scrap, can be another source.
2. Washing and size reduction. The PET is washed and ground into flake, and labels, caps made of other polymers and contaminants are separated out.
3. Drying and reprocessing. PET must be dried before melting. Recycled PET may also need processing to restore the melt properties needed for strap, because the material changes during its first life and during recycling.
4. Extrusion and stretching. The melt is extruded into a band, stretched to orient the polymer and develop strength, often embossed for grip, and wound into coils.

Every stage affects the finished strap. Contamination left in the flake, variation in the melt and changes in the blend of recycled and new material can all show up as variation between coils.

Why recycled content has become a purchasing question

Three policy signals were on the table by August 2019:

Date	Source	What it says
16 January 2018	EU Strategy for Plastics in a Circular Economy	Weak demand for recycled plastics is a major obstacle; the Commission launched a pledging campaign so that by 2025 ten million tonnes of recycled plastics find their way into new products
February 2019	UK plastic packaging tax consultation, reported by FoodNavigator on 19 February 2019	Proposed tax from April 2022 on plastic packaging produced in or imported into the UK with less than 30% recycled content
5 June 2019	Directive (EU) 2019/904, Article 6(5)	PET drinks bottles to contain at least 25% recycled plastic from 2025

The EU strategy also identifies quality and incidental contamination as barriers to using recycled plastics, and notes China’s decision to ban imports of certain plastic waste, which changes where much European plastic waste can go. The bottle targets in the single-use plastics directive add a further buyer of recycled PET. None of these documents sets a rule for strap, and none predicts its price, but together they explain why recycled content is becoming a purchasing question for strap as well.

What “recycled content” means in the UK proposal

The July 2019 summary of responses records the government’s preferred approach: a single 30% threshold, with a definition drawing on ISO 14021 that can include some pre-consumer and post-consumer material, whether mechanically or chemically recycled. The summary says the government will set out next steps at Budget 2019, so detailed scope is still open in August 2019.

The useful lesson for buyers is that “recycled” is not one thing. A claim may refer to post-consumer bottles, to factory scrap or to both, and the difference matters to customers who ask.

Questions to ask a strap supplier

• How much? The recycled share by weight, and whether it is measured per batch or averaged over a period.
• From where? The split between pre-consumer and post-consumer material, and the definition the supplier uses.
• How documented? The records behind the claim, and whether they can accompany each delivery.
• How consistent? How the supplier controls variation in feedstock and blend from coil to coil.
• Which data sheet? Whether published break strength and elongation values were obtained on the recycled grade being offered.
• Which joints? Whether joint evidence exists for the grade with your clips, seals or friction-weld tool.

Recycled content and performance are separate questions

A recycled-content percentage describes where the material came from. It does not describe break strength, elongation, retained tension or how the strap behaves in a clip or a weld. Those come from the strap specification and from tests on the actual grade.

Treat a change from a virgin grade to a recycled grade, or between recycled grades, as a change of strap. Run a trial with your own tools and closures, inspect joints and coils, and record the approved grade in the specification. The sample approval guide shows one way to keep that record.

Keep claims accurate downstream

If you pass recycled-content information to your own customers, pass on what the supplier documented, in the supplier’s terms, and keep the declarations on file. An unsupported percentage creates more risk than leaving the figure out.

When you enquire about PET strap, state the nominal width, thickness and the recycled-content information you need documented, and name the clips or tool you use. Send the details through the enquiry page.