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Cotton fabrics were water-repellent-finished by radical ultraviolet curing of silicone and urethane acrylates with different formulations. The fabrics were impregnated with undiluted resins and with toluene solutions or water emulsions. Moreover, cationic ultraviolet-curable systems were also investigated, such as an epoxy-functional polysiloxane and mixtures of an epoxy resin with hydroxyl-containing silicone additives. The gel content and polymerization yield were considered for the ultravioletcuring process evaluation. Water-resistance properties were determined in terms of the contact angle, wettability, moisture adsorption, and water vapor permeability measurements, whereas the morphology and surface composition of treated fabrics were examined with scanning electron microscopy and energy-dispersive X-ray analysis.

In this work knitted wool fabrics were coated by a Si:O x :C y :H z thin film with the aim to promote pilling resistance. The wool samples were plasma coated in a radio frequency (RF) glow discharge using hexamethyldisiloxane (HMDSO) as the precursor, in mixture with argon and oxygen gases, for different deposition times and reaction pressures, at constant discharge power. Deposited films were characterized by means of Fourier transform infrared (FTIR) spectroscopy and surface morphology by means of scanning electron microscopy; moreover, propensity to pilling of treated samples was investigated, showing that treated fabrics had a better pilling performance respect to untreated ones.

Polypyrrole is widely used as coating to produce electrically conductive textiles. Counter-ions (i.e. doping agents) were embedded in polypyrrole to improve electrical conductivity. Good electrical performances are required for several applications, such as microwave attenuation/electro-magnetic interference shielding, heat generation, electro-static discharge protection, sensing, and energy storage. In this work, a systematic study was carried out on the effects of doping agents in coating cotton fabrics with a thin polypyrrole layer. A total of 11 compounds were selected and compared as counter-ions. The electrical performances of the coated fabrics were assessed with measures of electrical conductivity. Moreover, evenness and morphology of the resulting polypyrrole layer were discussed. As the final result, the best performances in terms of electrical conductivity (i.e. low surface resistivity) were measured using on dicyclohexyl sulfosuccinate, 2,6-naphthalenedisulfonate or 1,5-naphthalenedisulfonate as doping agents. The weight increases after polypyrrole deposition on the fabrics were greater than 15% and polypyrrole deposited on the fibers as a uniform film. V C 2015Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42831.

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Silk grafting with methacrylic and epoxy monomers was studied with the aim to obtain high graft yields. With both monomer types optimum operating conditions of thermal grafting in water bath were established. In particular, three epoxy monomers were tested at various concentrations, at different temperatures and reaction times, with sodium chloride or sodium thiosulphate as catalysts. Optimum yields (76-82%) were found with Araldite DY-T for 2 h at 708C with 3M sodium chloride. The results were compared with those obtained with the same monomers by UV curing, radical with methacrylates and cationic with the epoxy resin. The UV curing efficiency was tested by gel content determinations. Thermal and UV cured fibers were then subjected to measurements of fibroin solubility in ethanolcalcium chloride-water mixture to evaluate the crosslinking degree. Except in the case of methacrylamide, radical UV curing yielded fibers more crosslinked than thermal treatment, or crosslinked to the same extent, whereas cationic UV curing showed lower crosslinking effects. The grafted fibers were characterized through DSC measurements and FTIR-ATR spectrometry. Finally, surface morphology of UV-cured samples was investigated through SEM analyses which showed that the better products could be obtained with UV curing at low add-on, mainly with dimethacrylates and Araldite DY-T, whereas the thermal grafting seems to be preferable for high add-on.