Recycled Polypropylene Packaging Composites

OBJECTIVES

An upcycled solution for paint container waste tailored for the product stewardship organisation Paintback, enabling sustainable product development and advancing circular economy goals

Develop recycled polypropylene (rPP) composites from mixed plastic paint container waste for use in sustainable products.

Create a technical catalogue of rPP materials, including data on contaminants and performance characteristics

Design an environmentally safe recycling and processing method

Team

Namita Roy Choudhury

Lead Researcher

Rajkamal Balu

Research Fellow

Partners

University of Southern Queensland (UniSQ)

Paintback Ltd

Progress

SUMMARY

Led by RMIT in partnership with the University of Southern Queensland and Paintback, this project is transforming difficult-to-recycle paint container waste into new polypropylene composites. The team has characterised the waste streams, developed a catalogue of recycled polypropylene (rPP), and created multiple material formulations using wood fibre as reinforcement. These composites were fabricated and tested for mechanical, thermal, and structural performance, revealing that a 20% fibre blend offers the best mechanical strength improvements. Durability tests showed expected degradation with repeated recycling and UV/weather exposure, and new formulations using hemp fibre are now in development. Results have been shared with Paintback and submitted to peer-reviewed journals. The project is moving toward industry trials to support large-scale use of these upcycled materials in products such as bollards, fences, and other outdoor infrastructure.

OPPORTUNITIES

Real-world product manufacturing using rPP composites in infrastructure applications like bollards, decking, and fences.

Industry collaboration with Paintback and plastic product manufacturers to scale up production

Potential for research funding to expand recycling innovation and fibre-reinforced composite development

Knowledge transfer between universities and industry to accelerate circular solutions

AS SEEN AT

Ending Plastic Waste Symposium, Melbourne, 2024 – Oral presentation titled “Biodegradable composite films with antibacterial properties for packaging applications”

Ending Plastic Waste Symposium, Melbourne, 2024 – Poster presentation titled “Upcycling post-consumer plastic waste: Natural fiber reinforced paint packaging composites”

AS SEEN IN

Polymers 2024, 16 (18), 2631. R Balu, S Sharma, R Roberts, J Vongsvivut, NR Choudhury “Upcycling post-consumer paint pail plastic waste”