Why Product Engineers and Sustainability Teams Must Collaborate Early

Why Product Engineers and Sustainability Teams Must Collaborate Early

Packaging is undergoing a fundamental shift, and the point of leverage has moved upstream.

For decades, packaging followed a linear model: take, make, use, dispose. That model worked when waste was largely invisible, and materials were inexpensive. It no longer does.

Today, changing regulations, rising ESG scrutiny, and growing material constraints are forcing brands to take responsibility for what happens to packaging after use. Packaging alone accounts for nearly 36% of global plastic waste, and close to 85% of it is mismanaged, ending up in landfills, open dumps, or the natural environment instead of being recycled.

What has changed is not awareness, but accountability.

Circularity is now judged on whether packaging can realistically be collected, sorted, recycled, and reused at scale. And that the success or failure of circularity collection is decided in the design phase. This places product and packaging engineers at the centre of sustainability outcomes. Early decisions around material structure, labels, adhesives, and colour determine whether a package is recyclable at all. Once a design is locked, fixing recyclability later is expensive, disruptive, and in many cases impossible.

Why Most Packaging Fails in the Recycling Stream

Most packaging does not fail in recycling plants; it fails at the design table.

Despite growing intent and awareness, a significant share of packaging still isn’t recycled. The reason is not a lack of collection alone, but the fact that many designs are fundamentally incompatible with how recycling systems actually work.

Multi-layer structures and contamination

Multi-material laminates such as PET–PE or PET–aluminium are often chosen for good reasons. They offer excellent barrier performance, improved shelf life, and protection for sensitive products.

However, these structures are complicated to separate using mechanical recycling processes. As a result, they are frequently rejected by recyclers or downgraded into lower-value outputs. What works well for performance often works poorly for circularity.

Inks, adhesives, and colourants

Inks, adhesives, and colourants are rarely selected with recycling in mind. Yet they play a major role in determining recycled material quality.

Carbon black pigments, for example, cannot be detected by standard optical sorting systems. This causes entire batches to be mis-sorted or discarded. Certain adhesives and inks also contaminate PET streams, reducing rPET quality and limiting food-grade applications.

These are small choices with large downstream consequences.

Inconsistent bale quality

Even when collection volumes are strong, PET feedstock often varies widely in quality. Mixed materials, incompatible labels, and contamination lead to inconsistent bale composition.

For recyclers, this inconsistency makes it significantly harder to produce high-quality, food-grade rPET. Collection alone is not enough if design choices undermine material consistency.

In circular systems, what works on the line must also work in the recycling stream.

The Missing Link: Early Collaboration

In many organisations, product engineers and sustainability teams are engaged at different stages of development.

Engineers are focused on strength, shelf life, machinability, cost, and speed to market. Sustainability teams are focused on regulatory compliance, recycled content targets, ESG reporting, and long-term impact.

Neither team is wrong. The problem is timing.

When sustainability enters the conversation late, it becomes a constraint. Teams are forced into redesigns, trade-offs, or last-minute compromises that increase cost and complexity.

Research consistently shows that 70–80% of a product’s environmental impact is determined during the design phase. Early collaboration allows teams to optimise performance and recyclability together, instead of trading one off against the other.

When engineers and sustainability teams work together early, circularity becomes a design parameter rather than a limitation.

Key Material Decisions That Shape Circularity

Many packaging components are selected for valid performance reasons. When circularity is a goal, these choices need to be evaluated early for their impact on recyclability.

Material structure

Mono-material PET structures are widely compatible with existing recycling infrastructure and support bottle-to-bottle applications.

PET–PE laminates, while offering strong barrier properties, make mechanical separation difficult and can reduce recycled resin quality. 

Labels, adhesives, and coatings

PVC labels are sometimes used for durability or cost advantages, but they can contaminate PET recycling streams and degrade rPET quality during processing.

PET-G sleeves and full-body shrink labels improve branding and shelf appeal, yet they reduce optical sortability if not carefully designed.

Barrier coatings enhance product protection, but certain formulations can interfere with melt filtration and decontamination during recycling.

Practical design guidance

To balance performance and circularity, design teams should consider:

• Wash-off adhesives to reduce contamination
• Limiting barrier coatings where possible
• Avoiding PVC and PET-G components on PET packaging when bottle-to-bottle recycling is the intended outcome

These decisions are far easier to make early than to correct later.

Designing for Food-Grade rPET Loops

Food-grade recycled PET is often treated as a recycling challenge. In reality, it is a design challenge.

Migration limits and decontamination

Food-grade rPET must meet strict migration limits to ensure that no harmful substances transfer to food. Achieving this requires advanced super-clean recycling technologies that use high temperatures, vacuum processes, and solid-state polycondensation to remove contaminants.

These technologies depend heavily on clean, compatible input material. Poor design choices upstream can block food-grade recycling regardless of how advanced the recycling process is.

Regulatory frameworks

Food-contact rPET is regulated through process-based approvals rather than material claims.  Across major markets, regulatory bodies assess the recycling process itself to ensure safety and compliance:

• India: The Food Safety and Standards Authority of India (FSSAI) permits the use of rPET for food contact under defined conditions.

• Europe: The European Food Safety Authority (EFSA) evaluates rPET recycling processes on a case-by-case basis.

• United States: The FDA issues Letters of No Objection (LNOs) for approved rPET recycling technologies.

Designing packaging that aligns with these regulatory frameworks simplifies approvals, reduces compliance costs, and enables scalable, food-grade recycling.

Moving from Recycling to Upcycling

Once recyclability is achieved, the next question is quality. Not all recycling delivers the same outcomes.

Closed-loop bottle-to-bottle systems

Global brands are increasingly investing in closed-loop PET systems where bottles are recycled back into bottles. These systems can reduce greenhouse gas emissions by 50–80% compared to virgin PET, while maintaining material performance.

Bottle-to-textile pathways

Recycled PET is also widely used in textiles, where it is converted into fibres and yarns. While this is not a closed loop, it extends material life and reduces dependence on virgin polyester.

In 2022, recycled polyester accounted for 14–15% of global polyester production, driven largely by PET bottle recycling. End use matters. Quality matters. And both are influenced by early design decisions.

Turning Circularity into a Design Advantage

Early collaboration enables packaging that performs on shelf, complies with regulations, and works in real-world recycling systems. It supports food-grade rPET loops, improves material value, and delivers measurable ESG outcomes.

Circularity works best when it is implemented at step one, not at the final stage.

Go Rewise works with packaging, R&D, and sustainability teams to bring this collaboration upstream through joint circular-design workshops that turn technical decisions into long-term material value.

If circularity is on your roadmap, the next step isn’t another checklist. It’s partnering with us to turn circular goals into practical design decisions. Join us for circular-design workshops that turn ideas into real impact.