Dyeing of UV irradiated cotton and polyester fabrics with multifunctional reactive and disperse dyes

Improving Biocompatibility of Polyester Fabrics through Polyurethane/Gelatin Complex Coating for Potential Vascular Application

Medical apparatus and instruments, such as vascular grafts, are first exposed to blood when they are implanted. Therefore, blood compatibility is considered to be the critical issue when constructing a vascular graft. In this regard, the coating method is verified to be an effective and simple approach to improve the blood compatibility as well as prevent the grafts from blood leakage. In this study, polyester fabric is chosen as the substrate to provide excellent mechanical properties while a coating layer of polyurethane is introduced to prevent the blood leakage. Furthermore, gelatin is coated on the substrate to mimic the native extracellular matrix together with the improvement of biocompatibility. XPS and FTIR analysis are performed for elemental and group analysis to determine the successful coating of polyurethane and gelatin on the polyester fabrics. In terms of blood compatibility, hemolysis and platelet adhesion are measured to investigate the anticoagulation performance. In vitro cell experiments also indicate that endothelial cells show good proliferation and morphology on the polyester fabric modified with such coating layers. Taken together, such polyester fabric coated with polyurethane and gelatin layers would have a promising potential in constructing vascular grafts with expected blood compatibility and biocompatibility without destroying the basic mechanical requirements for vascular applications.

Review on Intermolecular Forces between Dyes Used for Polyester Dyeing and Polyester Fiber

Polyester fiber is a manufactured fiber composed of synthetic linear macromolecules in the chain at least 85% by mass of an ester of diol and benzene-1, 4-dicarboxylic acid (terephthalic acid). Fibers of the most common polyester, poly(ethylene terephthalate) (PET or PET), are generally made from either terephthalic acid or dimethyl terephthalate together with ethylene glycol. Dyeing of polyester fabric with disperse dyes, polyester requires the use of dispersing agents. The chemical characteristics and general application conditions of disperse dyes are characterized by the absence of solubilizing groups and low molecular weight. Dye particles have a size ranging from 0.5 to 2.0 microns, generally contain –NH2, substituted –NH2, or –OH groups in the structure, and get attached with the fiber through H-bond and van der Waals force. Dyes are retained by the fiber by physical forces. Fastness properties are very high in polyester except in certain cases. The dye-fiber (PET) affinity is the result of different types of interactions, such as hydrogen bonds, dipole-dipole interactions, and van der Waals forces.

Cu nanoparticles synthesis using biological molecule of P. granatum seeds extract as reducing and capping agent: Growth mechanism and photo-catalytic activity

In view of extended applications of nanoparticles, the nanoparticles synthesis is an extensive research field and green synthesis is one of the co-friendly methodologies. Plant extract mediated synthesis of nanoparticles has gained much attention in current decade. In current investigation, copper nanoparticles (CuNPs) were prepared using P. granatum seeds extract (biological molecules) from copper(II) chloride salt. The synthesized CuNPs were characterized by UV-vis spectroscopy, X-ray diffraction measurements (XRD), scanning electron microscopy (SEM), Energy Dispersive X- Ray Spectroscopy (EDX), Fourier transform infra-red spectroscopy (FTIR) and atomic force microscopy techniques. The CuNPs formation occurred through reduction of metal ions followed by nucleation. The size of the CuNPs was in the range of 40-80nm (average particle size was 43.9nm) with semi spherical shape and uniformly distribution. Photocatalytic activity was evaluated by degrading methylene blue dye (150mg/L) at various CuNPs doses (10mg/L-100mg/L). The synthesized CuNPs showed excellent PCA for the degradation of methylene blue (MB) under solar light irradiation and up to 87.11% degradation was achieved. The oxidative degradation mechanism for MB was proposed. In view of efficient PCA, the use of biological molecules of P. granatum seeds extracts for the synthesis of CuNPs.