A reinforced double network (DN) hydrogel as a candidate for skin scaffold was prepared. It consists of Ocarboxymethyl chitosan, polyvinyl alcohol, honey, CaCl 2 , and graphene oxide. The various concentrations of CaCl 2 , namely, 30, 45, and 60 wt% were investigated. Besides, the GO content was studied as 3, 5, and 10 wt%. The structure of the DN was characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, energy dispersive X-ray and Brunauer-Emmett-Teller were evaluated. The mechanical properties were studied, too. It showed that the DN with 45 wt% CaCl 2 was optimized. Also, swelling mechanism was investigated. Moreover, with the increase in GO content, the mechanical strength was increased. The cytotoxicity was evaluated and it was indicated that DN with 45% CaCl 2 and 5% GO had an acceptable level of biocompatibility. Moreover, scanning electron microscopy images showed the porous structure of the DN nanocomposite. Thus, the DN has the potential to be applied in tissue engineering as a skin scaffold. POLYM. ENG. SCI., 60:889-899, 2020.

A new magnetic heterogeneous copper catalyst was prepared by immobilization of copper ions onto a cross-linked polymeric nanocomposite composed of starch grafted polyacrylamide and functionalized Fe3O4 magnetic nanoparticles.

No abstract

An easy and ecofriendly method for designing double‐network (DN) hydrogels based on chitosan and poly(vinyl alcohol) (PVA) with high mechanical performance is described. When covalent bonds in the networks are used as crosslinking agents in the achievement of a higher mechanical strength, the irreversible deformation of these hydrogels after a large force is applied is still one of the most important obstacles. To overcome this problem, we used physical crosslinking for both networks. The mechanical strength, surface morphology, and cytotoxicity of the films were studied by tensile testing, scanning electron microscopy analysis, and an MTT assay. The synthesized chitosan–PVA DN hydrogels showed a large improvement in the tensile strength to 11.52 MPa with an elongation of 265.6%. The surface morphologies of the films demonstrated the effective interactions between the two networks and a suitable porosity. Also, because of the use of a natural polymer and honey as a plasticizer, the cell culture indicated that the synthesized DN hydrogels had good biocompatibility (with 327.49 ± 11.22% viability) and could be used as capable biomaterials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45752.

No abstract