Background and purpose: Despite progresss in the techniques of surgery, there is still a lot of controversy about selection of the best technique and suture material. Many post operation complications such as infection, wound dehiscence, pain and sinus formation are related to the type of the suture used. In this study we compared the complications due to the absorbent suture (PDS) with a non absorbent suture (Nylon) in laparotomy operation. Materials and Methods: This clinical trial was performed on 120 patients referring to Imam Khomeini hospital, Sari, 2003-2005 for laparotomy. They were randomly divided in tow groups of equal number. The incision was repaired with PDS sutures in case and with Nylon suture in control group. All patients under study were followed up for one year. Data about chronic pain,wound dehiscence, infection, hernia and sinus formation were recorded and analyzed using SPSS software and Chi-square test. Results: In this study 120 patients (60 in case and 60 in control groups) were enrolled. After laparotomy, the incidence of chronic pain and sinus formation in case group was significantly less than the control group. There were no significant differences between the rate of infection, hernia and wound dehiscence in the two groups.Conclusion: No significant differences in the rate of infection, hernia and wound dehiscence between two types of suture materials were observed. However, application of PDS leads to less pain and sinus formation. Therefore, it can be a better choice in surgical incisions.

Polyaniline and polyamide (Nylon 6, 6) nanocomposites with silver were prepared by in-situ oxidative polymerization of aniline monomers in the presence of Ag salt. Nano particles of silver (NPs) were synthesized by controlled reduction of Ag+ ions with sodium borohydride at room temperature. Nylon 6, 6 was loaded with Ag nanoparticles by entrapment of Ag+ ions into the polymer network, followed by reduction. The nanocomposites were characterized by scanning electron microscopy (SEM), UV-Vis spectroscopy and FT-IR spectroscopy.

In recent years, biotechnology has formed many applications in dyeing and finishing sectors of textile industry. Enzymes are protein compounds which can participate in many reactions in textile wet processing. The purpose of this study is to improve Nylon 66 fiber structures and to study different properties including dye ability, moisture absorption, surface changes and color fastness using lipase enzyme. To that end, Nylon 66 fabrics were first treated with different concentrations of protease enzyme in water solution including 3, 6 and 9% o.w.f.. The dyeing process was then carried out on the treated fabrics with acid dyes. The results of color measurement on enzyme treated/dyed with these two class of dyes showed that the L* values of enzyme treated samples decreased and more decrease in L* value was observed with an increase in the enzyme percentage. The results of acid dyes exhaustion on treated fibers showed higher absorption of dyes on fibers. Tensile strength studies indicated that enzymatic processing decrease tenacity, modulus and elongation at break of Nylon 6 fabric. Thermal studies of enzyme treated sample did not show significant changes on orientation of fiber after enzyme treatment up to the temperature of 300°C. But increase in heating temperature of the sample in the range of 300-400°C showed considerable decrease in thermal degradation temperature of enzyme treated sample compared to non-treated one. The wash and light fastness properties of samples were measured according to ISO 105-CO5 and Daylight ISO 105-BO1. Enzyme treatment before dyeing process improves wash and light fastness of samples which could be the result of dyes penetration into the fibers.

The structures of polypropylene/Nylon 6 (PP/N6) blend filaments (10, and 20 wt% N6) with and without PP-g-MAH as compatibilizer are investigated. The blend filaments produced at the take-up speeds of 300 and 800 m/min were drawn with draw ratio of 3.5 and 2, respectively. Effects of blending of N6 with PP on birefringence, crystalline, and amorphous orientation factors of the composite filaments are studied. The amorphous orientation factor, fam of PP was found to increase with the increase in the amount of N6. The blend filaments behaved like iso-strain materials and most of the force in spinning and drawing was born by the PP phase. The presence of N6 fibrils helped the PP chain molecules to orient in amorphous regions. However, the crystalline factor, fc of PP decreased with increase in the Nylon fraction. This means that the presence of the crystals of N6 caused a decrease in the orientation of the PP crystals.

Background: Carpets are commonly used in our lives and are in contact with microorganisms.Antimicrobial agents should be used for the prevention of unwanted effects of microorganisms and control of their transmission. In this study, antimicrobial suspension of nano- silver was used for covering of Nylon carpets.Materials and methods: Different concentrations of nano- silver suspension were used by spraying method for covering of Nylon carpets. In different examinations, small pieces of carpets (0.5×1 cm2) were treated with bacterial suspensions ofStaphylococcus aureus and Escherichia coli. Before and after examination, the numbers of bacteria were counted and decreasing rate of them was determined.Results: In Nylon carpet with 25 ppm nano silver, decreasing rate of bacteria was 73.3%, while in carpets with 50 ppm and more, decreasing rate was 99.9%. Silver stability was assessed after 1 to 10 times of standard washing in 60 oC with household bleach for 20 min. Silvers of carpet surface were established and saved their antibacterial effects after washing.Conclusion: Spraying nano- silver solution on commodities and factory products can prevent transmission of many microorganisms and infection diseases.

This study was carried out to improve Nylon 6 fiber structure and to study different properties including dyeability, moisture absorption, surface changes and color fastness using lipase enzyme. For this purpose, Nylon 6 fabrics were first treated with different concentrations of lipase enzyme in water solution including 1, 2, 4 and 6% o.w.f. The dyeing process was then carried out on the treated fabrics with disperse and acid dyes. The results of color measurement on enzyme treated/dyed with these two class of dyes showed that the L* of enzyme treated samples decreased and more decrease in L* was observed with an increase in the enzyme percentage. The results of acid and disperse dyes exhaustion on treated fibers showed higher absorption of dyes on fibers. Tensile strength studies indicated that enzymatic processing decreases tenacity, modulus and elongation at break of Nylon 6 fabric. Thermal studies of enzyme treated sample did not show significant changes on orientation of fiber after enzyme treatment before the temperature of 300oC. But increase in heating temperature of the sample to the range of 300-400oC showed considerable decrease in thermal degradation temperature of enzyme treated sample compared to non-treated one. The wash and light fastnesses properties of samples were measured according to ISO 105-CO5 and Daylight ISO 105-BO1, respectively. Enzyme treatment before dyeing process improves wash and light fastnesses of samples which could be the result of dyes penetration into the fibers.