Aims: The simultaneous use of insulating polymers and nanostructures such as silver to produce triangular nanocomposites, with the reinforcement of effect of each other, can have better results in improving the mechanical properties and processability of polyaniline. The current study was conducted with the aim of preparation of Polyaniline/Polyvinyl Alcohol/Ag nanocomposite and characterization of its physicochemical and antibacterial properties.
Materials and Methods: In the present experimental research, polyaniline (PANI) was used as a conducting polymer, polyvinyl alcohol (PVA) was used as a biopolymer because of its biodegradable property. Ag nanoparticles also was considered as a reinforcing agent of thermal stability, mechanical and antibacterial property to prepare PANI-PVA-Ag nanocomposite.
The synthesis of PANI-PVA composite and PANI-PVA-Ag nanocomposite was performed through polyaniline and Ag addition in PVA solution. Different weight percent of components and Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and scanning electron microscope connected to the X-ray Diffraction System (EDX) were used to investigate the properties.
Findings: Thermal stability of the nanocomposite in comparison with pure PVA in temperatures above 400ᵒC was promoted. The presence of PANI, PVA, and Ag in the FTIR spectroscopy showed the compatibility of the nanocomposite components. The greatest tensile strength belonged to PANI/PVA/Ag nanocomposites with 88%, 9%, and 3%w/w.
Conclusion: The components of Polyaniline/Polyvinyl Alcohol/Ag are compatible. The presence of PANI and Ag nanoparticles in the structure of the nanocomposite improves its thermal stability than pure PVA at high temperatures. Polyaniline/Polyvinyl Alcohol/Ag canocomposite has inhibitory effect on gram-positive and gram-negative pathogenic bacteria. Reducing the weight percent of PVA or increasing the weight percent of PANI decrease the tensile strength.

Aims: In medicine, nanofiber can be used in wound dressing. The aim of this study was to prepare carboxymethyl cellulose/calcium alginate/polyvinyl alcohol/silver (CMC/Alg/PVA/Ag) nanocomposite by electrospinning method and to investigate its performance as wound dressing.
Materials and Methods: In the present experimental study, CMC biofilm was prepared by solution method. Then, calcium alginate/polyvinyl alcohol/silver (Alg/PVA/Ag) nanofiber was prepared by electrospining method in the optimal conditions and deposited on CMC film. Finally, the possibleof application of the product as wound dressing and its antibacterial and morphological properties, as well as permeability to water vapor were investigated.
Findings: CMC/Alg/PVA/Ag film had more permeability in comparison to Alg/PVA/Ag nanofibers and less water vapor permeability value in comparison to CMC film. The most sensivity belonged to Escherichia coli and Klebsiella pneumoniae gram-negative bacteria with inhibition zone diameter of 23mm and 24mm, respectively, and Staphylococcus aureus and Staphylococcus saprophyticus gram-positive bacteria with inhibition zone diameter of 21mm and 17mm, respectively, for CMC/Alg/PVA/Ag film. Also, the wound with CMC/Alg/PVA/Ag dressing significantly showed more healing speed in comparison to CMC dressings and CMC/Ag.
Conclusion: The use of CMC/Alg/PVA/Ag nanocomposite as wound dressing is possible. This dressing, with pores, allows the vapors to flow through the wound secretions, is impermeable to liquids and bacteria, but is permeable to oxygen and vapor; it is not allergenic and does not cause toxicity and chemical stimulation, transparent dressing and the possibility of seeing the wound is easily possible, it provides the moisture level needed for wound healing, it does not stick to the wound and as a result, its replacement is without pain and cheap.