Fire Retardant Textile and Leather (BioFRLeTex)

Background

The REACH regulation for chemical substances has a large impact on coating and finishing industry. Some flame retardants (FR) have been banned by EU regulations (REACH) for their environmental-unfriendliness. Therefore, there is a need to look into new alternative environmentally-friendly FR additives. Next to the regulation, industry is challenged by the increasing "bio, eco, natural and environmental friendly" consciousness of the consumer resulting in various textile and leather labels. Furthermore, environmental guidelines and regulations prescribe a reduction of CO2-emission. An important strategy to achieve this is the replacement of petrochemical resources by CO2-neutral alternative products such as biopolymers. Materials, totally based on CO2-neutral renewable resources (biobased materials), constitute a significant enhancement in respect to ecological and procedural aspects. The development of non-toxic biobased FR is still a challenge and demands the elaboration of novel formulations and compounds for coating and finishing.

Goals

The aim is to develop non-toxic, durable and biobased FR coatings and finishes. It is known that phosphorylated bio-based polymers (e.g. modified lignin) have a FR effect through barrier layer formation. It is also known that the combination of phosphorus and nitrogen-containing compounds often acts synergistically and is therefore already used in conventional FR systems. This principle should now be transferred to proteins. Proteins are suitable for developing biobased FR thanks to the high quantity of nitrogen. Chemical modification of proteins with phosphorous containing groups will increase the FR efficiency. For this, suitable non-food proteins are selected and modified by phosphorylation. The modified proteins will be characterized regarding their chemical composition, esp. nitrogen and phosphorus content. The implementation of the newly developed biobased FR in finishing and coating of leather and textiles will be evaluated. According to their performance, different end applications are envisaged (leathers, outdoor textiles, indoor and technical textiles).

Project consortium

Centexbel (Belgium), FILK e.V., (global coordinator, Germany) will be responsible for the management and dissemination of the results. Centexbel and FILK will perform the research.

Target group

coating / finishing companies (textile and leather)

producers of FR/additives

producers of ready-to-use FR formulations

Results

In the BioFRLeTex project, biobased flame retardant (FR) formulations for textiles were developed. To this end, various bio-based raw materials were screened, such as proteins, phenolic acids and polyols. The FR performance was tested according to the fire tests ISO 15025, NFPA 701, M-classification and Cal 117. The best FR formulations achieved M1 classification but none of the formulations passed the Cal 117 test.

In addition, bio-based FR from renewable raw materials such as vanillin, lignin, sorbitol, linseed oil and isosorbide were also synthesized. The biobased FR based on sorbitol and isosorbide were applied to cotton and were semi-permanent: after 5 wash cycles at 40°C treated cotton passed the ISO 15025 FR test. The FR based on vanillin, lignin and linseed oil were added to PU coating. The FR based on linseed oil had no FR effect, while PU coatings modified with FR based on vanillin and lignin passed the ISO 15025 test.