Investigation of the opto-thermo-mechanical properties of antimicrobial PET/TiO 2 fiber using the transport of intensity equation technique.

The transport of intensity equation (TIE) technique is used to investigate the effect of stretching and annealing conditions on the optical features and antimicrobial activity of polyethylene terephthalate (PET) fibers treated with TiO 2 nanoparticles. The main core of this paper gets the most preferable optical and mechanical properties for PET/TiO 2 fiber which maintains its antibacterial activity. The variation of the refractive index of untreated PET/TiO 2 fiber along its axis is studied. The computed tomography technique is used to investigate the morphology of the tested fiber and the distribution of TiO 2 nanoparticles inside the fiber. The effect of stretching on the refractive index and the density of TiO 2 nanoparticles of drawn PET/TiO 2 fibers are carried out. The antimicrobial activity of the PET/TiO 2 fibers are evaluated before and after stretching. The PET/TiO 2 fibers are annealed at different temperatures and durations. The influence of annealing on the variation of the refractive index of PET/TiO 2 fiber along its axis and the distribution of TiO 2 is investigated.