Fabric recycling inspired by a sandwich toaster

Four Monash University graduates have worked with the Vinyl Council of Australia (VCA), PVC manufacturers and recyclers to find solutions for recycling PVC-coated polyester fabric into new product.

Commonly used in advertising banners, truck tarpaulins and grain covers, over 1.2 million m² of advertising banner fabric alone goes to landfill in Australia every year - enough to cover the area of the Melbourne Cricket Ground 60 times. Through Victorian Government funding as part of the Future Designers Program, Monash students Kim Boon Sho, Jeremy Kee, Tom Millward and Patrick Sohn spent 12 weeks looking to economically reprocess the material into marketable product.

The students started with approaches to destroy, reconstitute and reprocess the material. It is a difficult composite material because of the polyester fibres, which would usually have to be separated and removed from the PVC; however, the students explored reprocessing the material without fibre extraction. Early reprocessing ideas were inspired by a sandwich toaster, which led to work on high-volume industrial granulators and roll heat presses.

A number of processes were tested. They included heating, vacuum forming and gluing layers of banners as a sheet. Another two processes included grinding the banners into 1-5 mm pieces. In one of these 97% of the polyester fibre was removed, and in another 100% of both polymers was retained.

The students pursued various tests of both these granulated material streams, which included experimenting in heating and flattening with the sandwich toaster; applying a heat and vacuum process to develop 3D shapes; and roto moulding. These tests were then repeated using industrial-scale equipment, such as hot rollers, at the various manufacturers’ premises. Both sheet and tile-like products were produced, some of which were found to be highly flexible, unbreakable, strong, smooth and glossy in appearance.

A report of the project and results is now being written and will be publicly available when complete. The VCA intends to continue to investigate ways to resolve the challenge to economically recycle PVC-coated polyester fabric into valuable new products in Australia.