Flame retardancy of flax fibers by pre-irradiation grafting of a phosphonate monomer

The functionalization of natural fibers using a phosphorus-containing monomer to improve flame retardancy is presented. Flax fabrics were modified pre-irradiation grafting method requiring electron beam radiation treatment. A phosphorus-based dimethyl(methacryloxy)methyl phosphonate (MAPC1) was used as retardant (FR) agent. process consists three main steps. First, flax irradiated at dose ranging between 5 and 100 kGy stored cold preserve the radicals created over long period before being immersed into an aqueous solution containing MAPC1 monomer. Finally, washing step treated carried out remove unreacted units well free oligomers polymers chains which not covalently bonded structure. presence on after irradiation confirmed paramagnetic resonance (EPR). Grafting efficiency evidenced by infrared spectroscopy (FTIR) quantified inductively coupled plasma atomic emission (ICP-AES). location grafted phosphorus polymer in fiber structure assessed scanning microscopy with energy dispersive X-ray spectrometry (SEM-EDX). impact onto thermal properties fire behavior evaluated. Thermogravimetric analysis (TGA), pyrolysis combustion flow calorimetry (PCFC) preliminary test for this assessment. Different parameters such dose, concentration, temperature reaction duration might monitored. In particular, it observed that homogeneous way bulk elementary leading high content around 2 wt% 10 up 7 kGy.