Electrospun membranes have potential applications in the field of waterproof and breathable textile products. However, challenges still exist to improve the breathability, and waterproof and mechanical properties of these microporous membranes. In this paper, a novel hydrophobic microporous nanofiber membrane was prepared via side-by-side electrospinning of fluorosilane-modified silica nanoparticles (F–SiO2) blended with synthesized polyurethane (PU) solution and composited with the polyacrylonitrile (PAN) solution. To prepare F–SiO2, SiO2 nanoparticles were hydrophobically modified by fluorosilane. Composite nanofiber membranes with different blending ratios of PU(F–SiO2)/PAN were fabricated via side-by-side electrospinning by controlling the extruding speed of two spinnerets. Experimental results indicated that regarding F–SiO2 as hydrophobic inorganic particle can improve the hydrophobic properties of PU nanofiber membrane. The prepared PAN/(F–SiO2/PU) nanofiber microporous membranes exhibit relatively excellent waterproof and mechanical properties as that robust tensile strength (19.5 MPa), preferable water vapor permeability [10.3 kg/(m2 d)], favorable water contact angle (137.2°), and superior mechanical properties. It was believed that the reinforced PAN/(F–SiO2/PU) nanofibrous composite membranes have potential applications in chemical protective clothing, army combat uniforms, self-cleaning materials, and other medical products.

As distinctive spontaneous polarization and far-infrared radiation characteristics, the natural mineral tourmaline (TM) has the regulatory effect on crystallization behavior, which possesses potential application in biomimetic mineralization and bone regeneration. In this study, polyurethane (PU) and gelatin (GE) membranes with different adding proportion of TM nanoparticles were prepared via electrospinning. Additionally, the effect of TM nanoparticles on the mineralization process of hydrophobic PU and hydrophilic GE was investigated by immersing the composite TM/PU and TM/GE electrospun membranes in the 10× simulated body fluid (10SBF) at 37 °C for varying periods of time. SEM images confirmed the well-dispersed TM nanoparticles in the PU and GE electrospun fibers. The mineralization deposition was characterized by the SEM, EDS, XRD, and FTIR, and it indicated that two types of calcium phosphate deposits with different Ca/P molar ratios were obtained when TM/PU membranes and TM/GE membranes were incubated in 10SBF. Honeycomb-like hydroxyapatite crystals nucleated and grew faster on TM/PU and TM/GE membranes than the pure PU and GE membranes, respectively. Furthermore, with the increase of the added TM nanoparticles in the composite membranes, more calcium phosphate crystals were precipitated. These results showed that the added TM nanoparticles were able to improve the mineralization of polymer fibrous membranes, which is potential for the composite bone scaffold.

Polyurethanes (PUs) were synthesized with polyols derived from castor oil and isophorone diisocyanate. The materials were evaluated for their mechanical properties using stress–strain curves, thermogravimetric analysis, differential scanning calorimetry, and contact angle analysis. The biological response of the materials was evaluated by determining their cell viability in vitro, antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa, and biological response in vivo of PUs by means of implanting them in Wistar rats. The cell proliferation on the materials was analyzed using mouse fibroblast L929, human fibroblast MRC-5, and adult human dermal fibroblast (HDFa) cells by the ISO 10993-5 method. The materials showed no toxic effects and promoted cell proliferation. Experiments performed in vivo for 30 days in mice showed that the materials neither affected the wound healing process nor caused adverse effects or severe injuries in the dorsal mid-cervical tissue or organs on histological evaluation. PUs synthesized can be used in biomedical devices.

Polyurethane catheters made of Pellethane 2363-80AE® were treated with a low temperature plasma developed for the decontamination of reusable polymer devices in hospitals. We investigated the modifications of the polymer surface by studying the topographic modifications, the chemical modifications, and their consequences on the wettability and bacterial adhesion. This study showed that plasma treatment modified the topography and grafted oxygen and nitrogen species onto the surface, resulting in an increase in the surface polarity. This effect could be correlated to the number of nitrogen atoms interacting with the surface. Moreover, this study demonstrated the significance of multiscale heterogeneities, and the complexity of industrial medical devices made from polymers. Their surface can be heterogeneous, and they contain additives that can migrate and change the surface composition.

A combination of transmission electron microscopy (TEM) and in situ tensile testing in an environmental scanning electron microscopy (ESEM) was used to evaluate the static bulk and dynamic surface morphologies of medical polyurethanes. TEM results showed phase-separated hard segment and soft segment structures. Surface morphology as a function of strain was studied using ESEM in conjunction with a tensometer.

the idea underscoring our proposed development is to take advantage of the good properties of both polyurethanes (pu) and silicones (pdms). the attributes which make polyurethanes attractive as materials for biomedical applications are their excellent physical–chemical properties, and their relatively good biocompatibility. against their use is the phenomenon of biodegradation that occurs after long-term implantation. silicones, on the other end, are known to have long-term biostability and good haemocompatibility subsequent to their use in several biomedical settings.