Fleece pullovers and jackets are as cosy as they are popular. However, something seems to be problematic about them: they are mostly made of polyester or, in other words, plastic, and when washed that is what they release: microplastics, or plastic in its tiniest format. This effect is due to the structure of the material. After dyeing, the circular machine-knitted plush fabric is roughened and shorn. That gives it more volume, but it quickly loses fibres as a result. They are so small that wastewater treatment plants may not be able to filter them out entirely and they may find their way into our waterways and seas, or as sewage sludge onto our fields. From there, it is possible the plastic works its way up the food chain and onto the plates from which we eat.
A joint project, TextileMission, deals with this problem of microplastics released by sportswear and outdoor textiles. The Hochschule Niederrhein University of Applied Sciences in Mönchengladbach is one of eight organisations and companies taking part in the project (https://www.hn-nrw.de/mikroplastik-in-sport-kleidung/). Their task, apart from washing tests and filtration of the washing fleet, is to optimise and develop textile surfaces that release smaller quantities of microplastics.
The work material of Professor Ellen Bendt, one of the university’s two female TextileMission project directors, includes a circular knitting machine. “Circular machine-knitted plush is the basis of fleece materials,” she says. “That is why our experiments on low-emission alternatives start at this very point.” The Hochschule Niederrhein is using an MPU 1.6 from Mayer & Cie. This machine, which knits plush, velour, terry and fleece fabrics, was chosen for two reasons. “For one we wanted a German manufacturer who will be on site quickly if questions arise. We are not, after all, talking about a standard application,” Ellen Bendt explains. “For another, we wanted to be sure that we are making full use of the opportunities available in the knitting sector.”
At present, conventional polyester spools are fitted on the MPU 1.6. Two sets of material have been tested already; many more are to follow. The experiments are still in their early days, the MPU 1.6 is brand new. Professor Bendt does not want to abandon polyester categorically, although she and her team look into alternative fibre materials. “What we are after is a mass-market solution, and on price grounds alone the solution must continue to be or to include polyester.” Whether that will be possible remains to be seen. Two years of research still lie ahead for the TextileMission project.