In the field of tissue engineering there is always a need for new engineered polymeric biomaterials which have ideal properties and functional customization. Unfortunately the demands for many biomedical applications need a set of properties that no polymers can fulfill. One method to satisfy these demands and providing desirable new biomaterials is by mixing two or more polymers. In this work, random nanofibrous blends of poly (e-caprolactone) (PCL) and polyglycolic acid (PGA) with various PCL/PGA compositions (100/0, 80/20, 65/35, 50/50, and 0/100) were fabricated by electrospinning method and characterized for soft-tissue engineering applications. Physical, chemical, thermal, and mechanical properties of PCL/PGA blend nanofibers were measured by scanning electron microscopy (SEM), porosimetry, contact angle measurement, water uptake, attenuated total reflectance Fourier transform-infrared spectroscopy (ATR-FT-IR), Xray diffraction (XRD), differential scanning calorimetric (DSC), dynamic mechanical thermal analysis (DMTA), and tensile measurements. Morphological characterization showed that the addition of PGA to PCL results in an increase in the average diameter of the nanofibers. According to these results, when the amount of PGA in the blend solution increased, the hydrophilicity and water uptake of the nanofibrous scaffolds increased concurrently, approaching those of PGA nanofibers. Differential scanning calorimetric studies showed that the PCL and PGA were miscible in the nanofibrous structure and the mechanical characterization under dry conditions showed that increasing PGA content results in a tremendous increase in the mechanical properties. In conclusion, the random nanofibrous PCL/PGA scaffold used in this study constitutes a promising material for soft-tissue engineering.

Bioadhesives are high molecular weight, biocompatible, biodegradable polymers used to join two surfaces where at least one of them is a living tissue. Bioadhesives are used for two main purposes, first as a replacement for surgical sutures and second as a substitute for traditional drug dosage systems. There are several considerations and issues associated with the use of biopolymers in suture‐less surgery as well as in drug delivery systems. Herein is presented a review of bioadhesives; the focus being on the adhesive properties. Bioadhesives for tissue joining are considered first, along with their main characteristics and advantages. That is followed by a discussion on the use of bioadhesives as drug carriers for efficient drug delivery.

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Polymer/clay nanocomposites have some unique properties due to combination of flame resistance and improved mechanical and thermal stability properties which are important to enhance the material quality and performance. The objective of this work was to investigate the effect of organically modified montmorillonite (org-MMT) on the thermal and flame retardant as well as hardness and mechanical properties of the nanocomposites based on the natural rubber (NR). It was shown that by the addition of 3 wt % of org-MMT to NR, its aging hardness rise was decreased more than 55% and the ignition time was delayed about 150%. The reduction in heat release rate peak value was equal to 54% compared to the pristine NR. Addition of org-MMT improved the thermal stability of the NR. Furthermore, nanocomposites which were calendared before curing showed much more thermal stability and fire resistance than those which contained similar amount of organoclay.

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