Dyed multifilaments (dyed with Terasil Blue), left: PP, middle: PP + 10% PA6, right: PP + 10% PET (dyeing temperature 120 °C)
Dyed multifilaments, left: PP, middle: PP +10 % PA6, right: PP +10 % PET, © ITA


The Situation

Polymer blends can be of great interest for processing in textiles and composites since a remarkably broad spectrum of properties can be obtained without having to develop a new polymer.

The blend could even outperform the properties of existing homopolymers or materials with tailored properties could be developed.

The Project

In the Blends4Innovation project, focus was on three combinations:

  • PP and PET (tested for clothing and composites),
  • PP and PA6 (tested for clothing and composites) and
  • PET and PA6 blends (tested only for technical applications).

It was already proven in the previous Cornet project Fibriltex that PP/PET blends are very promising. Therefore, Blends4Innovation further elaborated on this combination. PP multifilaments reinforced with PET microfibrils can be dyed using disperse dyes resulting in deeply dyed filaments being wash- and lightfast.

In general PP/PA6 blends showed to be less promising than PP/PET blends. Presence of PA6 microfibrils inside PP does not lead to an increase in mechanical properties. A decrease in shrinkage compared to neat PP was realised, but the effect was smaller than for blends with PET. Yet, the presence of PA6 in PP can reduce the hydrophobicity of PP filaments. Also, PP/PA6 blends result in dyeable PP filaments, but the obtained lightfastness is lower. PA6 based blends with a small amount of PP, aiming cost reduction, can be processed to multifilaments, but only in the presence of a compatibiliser, which again increases the cost. The knowledge obtained on the processing of PP/PA6 blends is of high interest for the re-processing of recycled waste, since this often contains multiple polymer types.

Finally, also for PET/PA6 blends, it was proven that they can be easily processed to textile filaments, without affecting the mechanical properties. Again, this shows the potential for the easy recycling of plastic waste. Moreover, the addition of PA6 to PET improves the dyeability of PET and might have a positive influence on the wearability. For this blend combination, the full textile processing chain has been evidenced going from filament extrusion, through textile processing (twistingknitting-weaving) and finally to dyeing.

The Benefit

In conclusion, the use of polymer blends can be of interest when improving the properties of yarns and composites and can give valuable insights for the reprocessing of plastic waste. This knowledge has been transferred to the industrial target groups and will be further disseminated. The positive feedbacks and cooperation of the companies during the User Committee meetings already showed the clear interest of companies to evaluate the blend technology in their applications.

For further information, please contact

Tobias Schlüter
+49 241 802 4751


Industrial Collective Research (Industrielle Gemeinschaftsforschung (IGF) - No. 115 EN