We report a mathematical model of the supercritical fluid foaming (SCF) from the poly(ε-caprolactone) (PCL) + CO 2 system based on the Laws of Conservation of Momentum and Conservation of Mass. The main model assumptions are constant temperature, negligible inertial effects, Newtonian and incompressible fluid, equal-sized bubble, constant bubbles density, and no interaction among bubbles. We present the model step-by-step, explain its parameter determination in detail, and demonstrate new insight into the model capability for predicting an unreported trend for bubble growth rate. For model validation, porous PCL scaffolds were fabricated using SCF at the pressure from 100 to 400 bar, temperature from 37 to 50 °C, the solubilization time of 2 h, and two-step depressurization rates (28.6 and 200 bar/min). The model results are in an acceptable agreement with the experimental data in terms of scaffold pore radius and scaffold porosity.

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Homogeneous nanofibers and non-cytotoxic HA/PVA membranes were produced by conventional electrospinning method followed by photocrosslinking process, without using any organic solvent. The membranes showed great potential for biomedical applications.

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Electrospinning has stood out as a promising technique for producing innovative dressings. In this regard, this study aimed to evaluate the effect of crosslinking with maleic anhydride (MA) at 0, 15, and 30 wt % on the morphological, physicochemical, and thermal properties and storage stability of electrospun hyaluronic acid /polyvinyl alcohol membranes loaded with Plantago major extract. The crosslinking enhanced the manufacturing process of the membranes. It reduced the average diameter of crosslinked nanofibers with 30 wt % MA by about 20 nm and increased the maximum decomposition temperature by 12 °C compared to control samples. Furthermore, crosslinking prevented the phase separation of the blend, making the crosslinked membranes more homogeneous. The storage stability results indicated that lower relative humidities favored the maintenance of the physical structure of the membranes, and the sorption isotherms obtained by the experimental data were better fitted by the Guggenheim−Anderson−de Boer model. This investigation suggested a promising approach to designing new wound healing dressings.

The COVID-19 pandemic has demonstrated that hygiene habits reduce the spread of the SARS-CoV-2 virus on contaminated surfaces. In this context, compounds with biocidal properties can act as surface coatings, especially in hospital environments, a source of pathogenic microorganisms. Therefore, the purpose of this review was to report an overview of recent studies with biocidal agents, focusing on polymeric surface modification. Methods such as direct incorporation, direct deposition, and chemical deposition of the microbial agent on the polymeric surface and surface modification without a microbial agent were discussed. Despite several studies in the literature, antimicrobial materials still face challenges such as commercialization, material stability in post-processing, and guarantee of long cycles. Moreover, effectiveness, toxicity, and final cost must be balanced. We also discussed the concept of antiviral activity and the action mode of the materials. Inorganic, organic materials, nanocomposites, and biopolymers have been addressed as viral inhibitors of several diseases. Lastly, we explored the functional validation of polymeric surface through characterization techniques.