Sustainable Flame-Retardant Flax Fabrics by Engineered Layer-by-Layer Surface Functionalization with Phytic Acid and Polyethylenimine

Abstract

New generation of mission-oriented fabrics meets advanced requirements; such as electrical conductivity, flame retardancy, and anti-bacterial properties. However, sustainability concerns still are on-demand in fabrication of multi-functional fabrics. In this work, we used a bio-based phosphorus molecule (phytic acid, PA) to reinforce flax fabrics against flame via layer-by-layer consecutive surface modification. First, the flax fabric was treated with PA. Then, polyethylenimine (PEI) was localized above it to create negative charges, and finally PA was deposited as top-layer. Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), and inductively-coupled plasma atomic emission spectrometry (ICP-AES) proved successful chemical treatment. Pyrolysis-combustion flow calorimetry (PCFC) showed significant drop by about 77% in the peak of heat release rate (pHRR) from 215 W/g for untreated to 50 W/g for treated flax fabric. Likewise, the total heat release (THR) decreased by more than three times from 11 to 3.2 kJ/g. Mechanical behavior of the treated flax fabric was completely different from untreated flax fabrics, changing from almost highly-strengthened behavior with short elongation at break to a rubber-like behavior with significantly higher elongation at break. Surface friction resistance was also improved, such that the abrasion resistance of the modified fabrics increased up to 30,000 rub cycles without rupture. Supplementary Information The online version contains supplementary material available at 10.1007/s10694-023-01387-7.

Enhancing Flame Retardancy of Flax Fabrics through Phytic Acid Grafting

“…The treated fabrics displayed an effective flame retardancy with 41% reduction in the peak heat rate release (pHRR). Ehsanimehr et al 25 also used PA to modify flax fabrics via the same method. The authors showed that values of pHRR of treated fabrics significantly decreased by about 77%.…”

“…Numerous studies have focused on environmentally friendly flame retardants, especially biobased ones . PA, which is a natural source of phosphorus, was highly investigated as a flame-retardant biomolecule. ,− …”