The annual production of fibres was about 84 million metric tonnes in 2011. 52 percent of these were synthetic. Polypropylene is the second largest of the synthetic fibres and it has had significant growth over the last years. The material surpassed the production of nylon and acrylic fibres early in the 2000’s and has continued growing aggressively since. It is now used to produce more than 6.1 million metric tonnes of fibres annually.
A major driver for polyolefin fibre use is the environmental aspect. Companies increasing their recyclability of products are looking for lightweight, “one material” concepts. If all components of the apparel, car or office furniture are constructed solely from polyolefins there is no need to separate materials before recycling. The result is increased recyclability. Polyolefins are one of the most environmentally friendly types of plastic according to Greenpeace rating and it is also available from biobased feedstock. The material consists of pure carbohydrate chains that are easily processed and demand less energy and lower temperatures during production than other plastics. Polyolefins also have lower density and is therefore lighter than many other plastics like for instance polyester.
One of the main problems with polyolefins has been its burning behaviour. The material is highly combustible. Various conventional, environmentally hazardous materials such as bromine have been used to modify burning behaviour in the past. But this limits the use since they deteriorate the environmental footprint and recyclability. As a result a number of industries are searching for non-halogenated flame retardants for polyolefin fibres. Such a solution would further increase the usability of the material with considerable environmental gains.
The objective of the project is to develop formulations, verify the theoretical concept and manufacture prototype compounds for testing. The compounds need to meet mechanical, processing and environmental requirements for polyolefin fibres. The aim of these materials is to substitute hazardous current solutions such as bromine and other halogens and increase the usability of polyolefin fibres for a wide range of products.
At the University of Borås the research group will focus on three work packages of the project:
- Melt spinning – pretesting
- Melt spinning – process optimization
- Textile manufacturing of modified fibre