Functional Modification Of Jute Fabrics Catalyzed By Enzymes

Jute fiber is one of the cheapest natural fibers that ranks only second to cotton in planting and being used by humans for long time. Jute fiber has luster, biodegradability and excellent moisture absorption and air permeability. Nowadays, its application has expanded from home textiles to industrial products, including nonwovens, geotextiles and fiber-reinforced composites. Hydrophilic jute fabrics have poor compatibility with the hydrophobic resins and for this are being discard as fiber reinforcing materials in composites. Thus, the hydrophobicity of jute fabrics needs to be improved to impart a good interfacial compatibility with hydrophobic resins.This work reports an eco-friendly approach to improve the hydrophobicity of jute fabrics via horseradish peroxidase?HRP?-catalyzed covalent grafting of butyl acrylate?BA? and 2,2,3,4,4,4-Hexafluorobutyl methacrylate?HFBMA?. The hydrophobic vinyl monomers were grafted onto the exposed lignins of jute's surface by means of free radical polymerization in the presence of HRP/H₂O₂/ACAC?acetylacetone? system. The coupling onto lignin-jute surface was demonstrated by attenuated total reflection-Fourier transform infrared spectroscopy?ATR-FTIR?, solid state nuclear magnetic resonance?solid-state 19 F NMR?, elemental analysis, x-ray photoelectron spectroscopy?XPS?, energy-dispersive x-ray spectroscopy?EDS?, matrix-assisted laser desorption/ionization mass spectrometry?MALDI-TOF MS? and scanning electron microscopy?SEM?. The hydrophobicity and oleophobicity of modified jute fabrics was estimated in terms of contact angle and wetting time. The results indicated that it was essential to attain vinyl monomers grafting polymerization onto jute surfaces in a HRP/H₂O₂/ACAC system. Moreover, the grafting of vinyl monomers led to the hydrophobicity increases of 53.86% and 61.03% in contact angle of grafted jute fabrics with BA and HFBMA when comparing with unmodified jute fabrics, respectively. Both vinyl monomers demonstrated high propensity to be polymerized by HRP in the presence of H₂O₂ with acquiring ability to act as high-performance composites with hydrophobic resins.Two fluorinated monomers, 4-[4-?Trifluoromethyl?phenoxy]phenol?TFMPP? and 1H,1H-Perfluorononylamine?PFNL? were efficiently grafted onto the exposed lignin of jute's surface by laccase mediated reaction. Their grafting onto the lignin-exposed jute was demonstrated by Fourier transform infrared-attenuated total reflection spectroscopy?FTIR-ATR?, X-ray photoelectron spectroscopy?XPS? and scanning electron microscopy?SEM?. The coupling of fluorophenol and fluoramine onto a complex lignin model compound?2-methoxy-4-propylphenol??MP? was confirmed by nuclear magnetic resonance?1H NMR?. Laccase-catalyzed grafting of both fluorinated monomers led to 41.94% and 46.35% increase in contact angle for TFMPP and PFNL, respectively. An oil static contact angle of 117.16? and oil wetting time values higher than 30 min obtained for PFNL-grafted jute also demonstrated the oleophobic behavior of jute samples after laccase-mediated oxidation. The laccase-related oxidation and formation of homopolymers and copolymers was also confirmed by UV-visible spectra of treatment solutions supernatant in the UV-visible region.The modified jute fabrics can be gratfed with hydrophobic resins, which act as high-performance composites.