Alpaca fleece is a luxurious fibre with excellent softness, great warmth, good lustre and strength. Unlike similar fibres such as wool, alpaca fibres come in 22 natural colours. Global production of alpaca fibre was estimated at 6000 tonnes in 2015 with the price reaching $US16 per kg.
About 20–30 per cent of fibre is lost during shearing and processing. These short and non-spinnable fibres mostly end in landfill, are fed into incinerators or used as low-grade animal feed.
Novel, renewable materials
IFM researchers, led by Dr Maryam Naebe are investigating the use of these currently wasted fibres as a natural colourant for dyeing acrylic fibres.
Melanin is the pigment primarily responsible for the different colours of alpaca fibres. Conventional extraction of melanin from fibres uses toxic acids and alkalis. The IFM team is using a chemical-free technique to produce the pigments from waste alpaca fibres and then applying the pigments to colour polyacrylonitrile (PAN) fibres in wet spinning. This process could also be used to replace synthetic dyes for dyeing wet spun fibres.
Using our expertise on producing powders from natural fibres, Dr Naebe and her colleagues are developing a chemical free pathway to colour acrylic fibres. The waste alpaca fibres are mechanically milled into a powder, which is applied during fibre spinning to colour the acrylic fibres.
In the conventional dyeing process, acrylic fibres are treated with synthetic dyes. Other chemicals are used to accelerate the process and produce an even result. All these dyes and chemicals also produce massive amounts of waste-water into the environment.
- Alpaca fibre producers will get returns from previously unprofitable waste and non-spinnable alpaca fibres
- The amount of water used to produce coloured acrylic fibres is reduced
- The level of chemical pollutants is greatly reduced
- Comfort properties like moisture and wicking of acrylic fibres are enhanced
- When colourant is embedded into the polymer chains during preparation of the dyeing solution, the wash and light fastness of the resultant fibres is increased.