فصلنامه مواد پیشرفته و پوشش های نوین
پیاپی 17 (تابستان 1395)

In this research an in situ suspentipon polymerization of methyl methacrylate in aqua media was performed based on the optimum concentration of poly vinyl pyrolidon as surface active agent and azobisisobutyronitrilas initiator, in which least amount of gel was produced. At the next step the surface of nano silica was modified by coupling process and dispersed homogeneously throughout of the polymeric matrix. At the end of polymerization the nano composite of poly methyl methacrylate – silica beads were collected, dried and dissolved in a hydrocarbon solvent. In this way a resin solution of 30% solid content was prepared and used as coating for different types of substrates like ABS and PVC .The electronic macroscopic images indicates the nano silica has uniformly dispersed. The flourier transform infrared spectroscopy was clearly confirmed the chemical structure of nano silica. Also the result of gel permeation chromatography stating the mean molecular weight of polymers contains nano silica was increased. The analysis of differential scanning calorimetry was shown that the glass transition temperature of the one contains 2% nano silica enhanced 7 degree centigrade. The light scattering percentage indicates the decreasment of light transition at the samples contains 2% nanosilica was negligible.

The effect of an imidazolin hydrochloride ionic liquid was studied in dyeing process of cotton fabric using reactive dye. Different concentrations of ionic liquid from 0.5 to 10 g/l were used during the dyeing process. Reflectance, morphological, tensile and fastness properties were analyzed. The results showed that the ionic liquid can significantly improve the dye-uptake of the cotton fabric. Maximum ΔE*ab was obtained for cotton fabric sample which was dyed with 3 g/l ionic liquid. SEM images of the cotton dyed fibers with ionic liquid showed the surface variations and creation of the cracks on the longitudinal surface of fiber samples. Also the warp and weft yarns breaking strength of dyed fabrics were slightly reduced by using ionic liquid. Washing fastness of the samples showed no variation. However, the light fastness values were slightly decreased.

The aim of this study is preparation and evaluation of regenerated cellulose nanofibers treated with cyclodextrin molecules in order to release gradually of particles from the surface of textile. In this study, cellulosic nanofibers were prepared by electrospinning of cellulose acetate solution in the mixed solvents of acetone and dimethyl sulfoxide and then prepared cellulose acetate nanofibers were deacetylated. Acetate nanofibers were deacetylated and evaluated with both Potassium hydroxide and Sodium hydroxide. In order to graft β-Cyclodextrins molecules to regenerated cellulose nanofibers, the method of crosslinking by polycarboxilic acids was used. Physical and chemical properties of prepared nanofibers were investigated by SEM, FTIR and DSC. In order to evaluation the performance of prepared nanofibers, Gentamicin antibiotic molecules were loaded into cyclodextrins’ cavities and the rate of delivery was measured by UV-visible spectrophotometer. According to obtained results, it is obvious that presence of cyclodextrins on the surface of nanofibers has a great impact on controlled release of guest molecules from the surface of textile.

Development of flexible Photovoltaic devices with printing technology needs to special inks based on conducting and semi-conducting materials. Poly(3,4-ethylenedioxythiophene): Polystyrene sulfonate (PEDOT:PSS) is one of the conducting polymers that is useful in this technology. This polymer is used in the various photovoltaic devices such as light emitting diodes and solar cells. In this research an inkjet ink of PEDOT:PSS was formulated with various co-solvents. It was investigated the printability and post printing properties such as surface conductivity and morphology. The results showed that dimethylformamid is the best co-solvent for printing PEDOT:PSS inkjet ink.

Organic zinc-rich epoxy coating serves a range of industries over the years have raised and satisfactory performance . Micaceous iron oxide (MIO) pigments are widely used in anti-corrosion coating performance is barrier. In The research, the zinc-rich epoxy paint splvent –based formulations and their application on carbon steel panels were studied and compared with the standard 5 to 40 percent of zinc dust was replaced by MIO. The coatings were applied on low carbon steel panels and the coatings was evaluated using adhesion , cupping , impact , conical bending , hardness , methyl ethyl ketone rub test , also optical microscopy , electrochemical impedance spectroscopy (EIS) , open circuit potential (OCP) measurements and salt fog tests were used for electrochemical evaluation of coared panelsoptical microscopy was used for obsering the dispesion of MIO pigments in coatings results revealed that the coating with 40 % of zinc replaced by MIO showed better mechanical properties and greater corrosion resistance than the other samples . Overall results showed that more replacement of zinc with MIO up to 40% led to decrese the coating reactivity and increased the time of cathodic protection about 40%. .

Implementing carbon base fillers e.g. carbon black pigments in a polymer binder is one of the most widely used methods for making conductive coatings. The grade of carbon black pigment and formulating parameters such as pigment concentration and additives have a large impact on the quality of the resistivity characteristics of the coating. In this study, samples of various amounts of conductive carbon black pigment in the acrylic polymer is provided. Based on the data obtained from these samples a mathematical model has been developed to determine the resistivity of the coating as a function of the carbon black pigment concentration. It is shown that how the performance of a typical conductive coating can be evaluated quantitatively throughout this model.

In this study, the use of a fluorescent material most widely used in dyeing wool fibers is studied used in the manufacture of carpet fiber. In this regard, the 4-Amino-N-methoxy propyl - 8, 1-naphthalimide used as a fluorescent dye and theeffect of various parameters has been investigated such as temperature, time, pH and concentration of the dye bath on the results of dyeing wool fibers. Criteria for selecting optimum conditions in these tests dyeing was visually and running that dyeing fibers to achieve the desired color strength and luminescence. The results showed that the time, temperature and concentration of the dye to reach the highest luminescence intensity, they are 60 minutes, boiling point and 1%. Moreover, the intensity of luminescence is independent of pH bathroom was dyed fibers. In order to allow the use of dyed fibers for carpet production, fastness properties such as fastness, light fastness and rubbing fastness in accordance with international standards and luminescence intensity was assessed through Spectro luminescence. The results showed that dyed the relatively good fastness, good light fastness and rubbing fastness is excellent.