Foil-backing - Innovative foil backing for textile, recyclable mono-material floor coverings based on recycled polyamides

Textile floor coverings removed from a building after use are usually sent for thermal recycling, which is an unsatisfactory situation, especially if the waste is valuable engineering plastics such as PA6 or PA6.6.

Together with the Institute of Plastics Processing (IKV), TFI is therefore developing a recyclable textile floor covering with a final recycled PA6 content (rPA6) of up to 90% by weight as part of this research project. An innovative film coating is to be realized for this purpose.

Preliminary investigations by the research institutes IKV and TFI show that recyclable textile floor coverings made of PA6 can be produced by combining film extrusion and backstitch bonding with the help of thermobonding technology. One challenge is the design of a process for material recycling from old carpets with high levels of contaminants to a high-quality flat film.

In preliminary tests with a film (200 µm), the temperature and dwell time parameters were varied. At 241°C and 9 s, the first contact points between the film and the dead pole were created (Fig. area C). Without the film, the pile yarns melt to such an extent that they sink into the primary backing and the “dead pile bridges” between the individual tufts are dissolved. As a result, there is no longer a connection within the backstitch, which results in low tuft integration (Fig. area A). There are individual areas where the film has melted more strongly onto the backstitch but has not completely penetrated the primary backing. The majority of the area shows only slight adhesion (Fig. area B). In general, the results suggest that it is possible for the backstitch to fuse with the PA films.

Faultless application of the flat film, without the inclusion of e.g. air bubbles or folds, in the thermal bonding process, which has hardly been researched for textile floor coverings, represents a further challenge.

Fig. Thermobonding with 200 µm film, left, only thermobonding with very strongly fused backstitch (A), individual areas with better adhesion to the dead pile;(C), slight adhesion with air inclusions (B)

Funding program and project number

IGF 22910 N

Supported by:

Duration

01.04.2023 – 31.03.2025