CS/PVA/SA hydrogels modified with mesoporous Ag2O/SiO2 and curcumin nanoparticles for antibacterial biopolymer film.

Fused Depositional Modeling (FDM) is one of the common methods for 3D printing of polymers, which is expanding in various industrial applications, scienti c researches, and engineering applications due to its ability to make complex parts. In this research, molecular dynamics (MDs) simulation has been used to predict the physical and mechanical properties. Then, the mechanical properties of the printed parts are obtained. The mechanical properties of 3D printed parts strongly depend on the correct selection of processing parameters. In this study, the effect of three important parameters such as in ll density, printing speed, and layer thickness are investigated on the tensile properties of PLA specimens. For this purpose, standard specimens with four in ll densities of 20%, 40%, 60% and 80%, two speeds of 20 mm/s, and 40 mm/s, and two thicknesses of 0.1 mm and 0.2 mm are printed and tested under quasistatic tensile test. In all printed specimens, the print angle is ± 45°. The experimental results show that the in ll density in comparison to the other two parameters has signi cant effect on mechanical properties such as modulus of elasticity, ultimate strength, and failure strain. According to these results, by increasing the in ll density, the stiffness and strength of the specimens increases considerably. At in ll density of 80%, the specimens has the highest stiffness and strength, but it exhibits a brittle behavior. Moreover, it can be deduced that by reducing the layer thickness although the modulus of elasticity increases a little, ductility is greatly affected.

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Fused Depositional Modeling (FDM) is one of the common methods for 3D printing of polymers, which is expanding in various industrial applications, scientific researches, and engineering applications due to its ability to make complex parts. In this research, molecular dynamics (MDs) simulation has been used to predict the physical and mechanical properties. Then, the mechanical properties of the printed parts are obtained. The mechanical properties of 3D printed parts strongly depend on the correct selection of processing parameters. In this study, the effect of three important parameters such as infill density, printing speed, and layer thickness are investigated on the tensile properties of PLA specimens. For this purpose, standard specimens with four infill densities of 20%, 40%, 60% and 80%, two speeds of 20 mm/s, and 40 mm/s, and two thicknesses of 0.1 mm and 0.2 mm are printed and tested under quasi-static tensile test. In all printed specimens, the print angle is ± 45°. The experimental results show that the infill density in comparison to the other two parameters has significant effect on mechanical properties such as modulus of elasticity, ultimate strength, and failure strain. According to these results, by increasing the infill density, the stiffness and strength of the specimens increases considerably. At infill density of 80%, the specimens has the highest stiffness and strength, but it exhibits a brittle behavior. Moreover, it can be deduced that by reducing the layer thickness although the modulus of elasticity increases a little, ductility is greatly affected.

Today, various commercial dressings have been developed and introduced to the market. The diversity makes it difficult for the nurse to choose the right type. Although the most important reason to use a wound dress is to protect the wound from infection and prevent infection, but in fact, the main purpose of using these materials is to speed up the wound healing process. Traumatic injuries result in an epithelial wound that disrupts the continuity of the skin surface. These differences reveal as abrasions, punctures, and injuries. Wounds are divided into two types; the skin is either cut or ruptured, including deep wounds and bruises, or surface wounds. Expedited wound healing has been considered since the archaic era of human civilization, with the earliest reported case from the Ancient Egyptians. Wound lesions in mummified humans were observed to be cover with animal skin, with signs of (primary/secondary) wound healing present. A "new wound dressing" is an advanced wound dress used in wound management as biocompatible and biodegradable biomaterials that heal wounds and burns. In the past, it was believed that dry wounds had expedited healing and wet wounds have been found to promote using re-epithelization and result in reduced scar formation. Wounds can be treated using various types of natural polymers and materials. Also, techniques like electrospinning and freeze-drying techniques can be used for the fabrication of standard wound dress. These wounds are associated with bandages, inflammation, bleeding, pain, and pus. In this work, we consider various types of wounds and techniques to treat the wound. Susceptibility to these areas, due to special symptoms for each of them. Products like hydrogels, hydrocolloids, films, sponges, and nano-fiber polymeric materials are used to promote healing. In this review, we examine the ideal products for the treatment of wounds in diabetic patients.