Flame retardant property of flax fabrics coated by extracellular polymeric substances recovered from both activated sludge and aerobic granular sludge

Nam Kyeun Kim; Ningtao Mao; Richard Lin; Debes Bhattacharyya; Mark C M van Loosdrecht; Yuemei Lin

doi:10.1016/j.watres.2019.115344

Flame retardant property of flax fabrics coated by extracellular polymeric substances recovered from both activated sludge and aerobic granular sludge

Water Res. 2020 Mar 1:170:115344. doi: 10.1016/j.watres.2019.115344. Epub 2019 Nov 29.

Authors

Nam Kyeun Kim¹, Ningtao Mao², Richard Lin¹, Debes Bhattacharyya¹, Mark C M van Loosdrecht³, Yuemei Lin⁴

Affiliations

¹ Centre for Advanced Composite Materials, Mechanical Engineering Department, University of Auckland, New Zealand.
² Performance Textiles and Clothing Research Group, School of Design, University of Leeds, Leeds, LS 2 9JT, UK.
³ Department of Biotechnology, Delft University of Technology, Delft, the Netherlands.
⁴ Department of Biotechnology, Delft University of Technology, Delft, the Netherlands. Electronic address: Yuemei.Lin@tudelft.nl.

PMID: 31812817
DOI: 10.1016/j.watres.2019.115344

Abstract

In this research, extracellular polymeric substances (EPS), such as EPS_flocs and EPS_granules, were successfully extracted from activated and aerobic granular sludge, respectively, and tested as bio-based flame retardant materials. Flax fabric was coated by the biopolymeric substances and its flammability was evaluated based on a vertical burning test defined in US Federal Aviation Regulation. Both EPS_flocs and EPS_granules coated flax fabrics achieved the self-extinguishment due to effective char formation. In particular, the result of the EPS_granules coated sample met the aviation requirements for the aircraft interior. Moreover, the presence of carbonated hydroxyapatite was identified in EPS_granules char residue by using FTIR and XRD analysis. It can contribute to the self-extinguishing property of the fabric by enhancing char formation. Thermogravimetric analysis also demonstrated that EPS_granules coated flax was able to produce greater amount of char residue and its decomposition rate was significantly reduced. This research indicates that there is a great potential to use this biopolymer as a resource for developing high performance bio-inspired flame retardant materials and contribute to a circular economy.

Keywords: Aerobic granular sludge; Extracellular polymeric substance; Flame retardant; Flax fabric.

MeSH terms

Extracellular Polymeric Substance Matrix
Flame Retardants*
Flax*
Sewage
Textiles

Substances

Flame Retardants
Sewage