Researchers at the Institute of Chemical Technology (ICT), Mumbai, have developed a bio-based flame-retardant coating for polyester fabrics. The coating uses eugenol from clove oil and a phosphorus compound called DOPO.
The study was led by Akash R. Parvate, with contributions from Suyog Patil under the supervision of Aarti P. More. The findings were published in Polymer Bulletin.
Bio-Based Flame-Retardant Coating
The researchers developed a compound called Eugenol-DOPO. Eugenol comes from clove oil and contains an aromatic structure that can support polymer formation.
DOPO is an organophosphorus compound used in flame-retardant applications. The researchers bonded DOPO with eugenol to create a reactive flame-retardant molecule.
They then used Eugenol-DOPO as part of a waterborne polyurethane formulation. This approach chemically locks the flame-retardant component into the polyurethane network.
Improved Thermal Stability
The modified polyurethane coating showed higher thermal stability than the unmodified coating. Testing also showed slower mass loss during degradation.
The coated material produced more residual char after heating. Char can form a protective layer during burning. It helps reduce heat transfer and limits the release of flammable gases.
The phosphorus component also supports flame suppression. DOPO-derived phosphorus species can interfere with combustion reactions.
The eugenol structure supports char formation in the condensed phase. The polyurethane system also contains nitrogen, which can work with phosphorus to improve flame-retardant performance.
Application on Polyester Fabrics
The researchers applied the modified polyurethane coatings to polyester fabrics. The treated fabrics showed improved flame resistance and thermal performance.
Analysis confirmed that the polyurethane coating was deposited on the textile surface. The fabrics also retained flexibility and good coating adhesion.
This is important for textile applications. Excessive flame-retardant additives can make fabrics stiff or affect their surface properties.
Potential for Sustainable Textile Protection
The research offers a halogen-free approach to flame-retardant textile coatings. It combines a clove-derived material with phosphorus-based flame-retardant chemistry.
The use of waterborne polyurethane also reduces the need for conventional solvent-based coating systems.
The researchers noted that further testing is needed before commercial use. Long-term durability, washing resistance and full combustion performance require additional evaluation.
The study shows the potential of bio-based flame-retardant coatings for polyester textiles. The approach could also support future research into flame-retardant polymer systems for other applications.
