Driving Sustainable Solutions in Plastic Injection Contract Manufacturing

Sustainability has rapidly shifted from a “nice-to-have” to a fundamental expectation across every industry that relies on plastic components.

As global regulations tighten and brands face increasing pressure to reduce their environmental footprint, forward-thinking manufacturers must integrate sustainable practices throughout the entire product lifecycle. At Rosti, sustainable manufacturing is not just a service – it is a responsibility and a strategic advantage.

Designing for circularity from day one

Sustainability in plastic injection moulding begins long before resin enters a machine. Thoughtful product design can dramatically reduce environmental impact by minimising material consumption, enabling repair or refurbishment, and making end-of-life recovery feasible.

At Rosti, our early-stage engineering support focuses on

• Lightweighting to reduce raw material use and CO₂ impact
• Optimised geometries that enhance strength without adding unnecessary mass
• Material selection guidance including recyclates, biobased polymers, and high-performance alternatives with lower embodied carbon
• Design for recyclability for closed-loop or open-loop circular systems

This combination helps customers achieve more sustainable products without compromising performance, safety, or aesthetics.

Smarter materials for a lower-carbon footprint

The choice of polymers has a major influence on a product’s sustainability profile. Rosti actively evaluates and validates a wide portfolio of materials:

• Post-consumer and post-industrial recyclates that offer high-quality performance in consumer, industrial and technical applications
• Bio-based polymers derived from renewable feedstocks
• Mass-balanced materials certified to ISCC standards to support traceability and transparency
• Advanced engineering polymers that deliver longer part life, reducing replacement cycles

By collaborating closely with leading material suppliers and continuously benchmarking against competitor practices, Rosti ensures customers adopt future-proof solutions that meet both market demands and regulatory requirements.

Energy-efficient, high-performance manufacturing

Injection moulding is energy-intensive, but significant gains can be achieved through efficient tooling, automation, and machine optimisation. Key areas where Rosti reduces emissions include:

• High-efficiency machines that consume less energy per cycle
• Tooling innovations such as conformal cooling and optimised gating to shorten cycle times
• Predictive process monitoring to avoid scrap
• Automated assembly that enhances precision and reduces waste
• Modernised facilities where energy use, water consumption, ventilation and waste handling are all carefully controlled

These investments support customers looking to meet their own science-based targets and Scope 3 expectations.

Closing the loop through responsible waste and recycling streams

True sustainability goes beyond making parts efficiently. It also requires managing waste responsibly and ensuring materials stay in circulation. Rosti’s sites integrate:

• Segregated recycling streams for clean, uncontaminated scrap
• Granulation and reprocessing for internal reuse
• Partnerships with external recycling specialists where materials cannot be processed in-house
• Data-driven waste reporting to support customer ESG reporting

This enables both environmental benefits and cost efficiencies – a win-win for customers in competitive markets.

Collaboration is the key

Sustainable solutions are not created in isolation. They emerge when customers, engineers, suppliers and sustainability specialists work together toward shared goals. Rosti’s collaborative model ensures that every project includes clear sustainability advice, measurable objectives, and continual optimisation throughout the entire manufacturing journey.