Silicone drug delivery implants are widely used, but their fabrication often relies on non‑standardized, empirically tuned protocols that limit reproducibility and transfer across labs. Here, we present a reproducible and generalizable fabrication workflow that brings together design rules, process settings, and validation for rapid fabrication of complex thin-walled biocompatible silicone implants. We outline mold design choices, including vents and micro refill-valve/filter placement, and post‑processing to make smooth inner surfaces, and we compare molds using an applied release agent (mold‑release chemical) versus molds coated with a parylene‑C barrier. Contact angle, Fourier transform infrared spectroscopy (FT-IR), and residue analyses show that parylene‑C prevents cure inhibition and enables clean demolding. We then link spin‑coating variables to membrane thickness and use rheology to guide material selection for pattern fidelity. We also correlate the curing time with network formation and extractable content. Device-level cross-sectional analyses and cytocompatibility assays are also conducted, with the assays indicating excellent compatibility with cells. Taken together, this work provides practical, transferable practice guidance and a reference workflow that other laboratories can adopt to make consistent silicone drug delivery implants and move the field toward standardization.
Biomass/biowaste-derived polymers are an advanced approach for the preparation of biodegradable and environmentally friendly polymers from renewable sources. This review focuses on methods for preparing, characterizing, and applying polymers derived from agricultural waste, animal waste, food leftovers, forestry residues, aquatic biomass, and industrial waste, among others. In this review, major classes, including lignin-based polymers, microbial polymers, cellulose-based polymers, starch-based polymers, and protein polymers, are discussed and characterized with structural, thermal, and mechanical analyses. Particularly, researchers highlight widely studied polymers such as polyhydroxyalkanoates (PHA) and polylactic acid (PLA) due to their growing industrial and biomedical relevance. The applications of these polymers in environmental remediation, biofuels, pharmaceuticals, food industry, and packaging are discussed. Comparative assessment indicates that lignocellulosic biomass is the most suitable feedstock for large-scale polymer production because of its abundance, low cost, and compatibility with existing biorefinery systems, although intensive pretreatment remains a limitation. Food and kitchen waste enables efficient microbial conversion to PHA and PLA, whereas marine biowaste is better suited to high-value biomedical and specialty applications. Among the synthesis routes, microbial fermentation offers favorable environmental performance, while chemical polymerization provides greater molecular control and industrial scalability. In terms of material performance, PLA exhibits comparatively high mechanical strength, whereas PHA provides faster biodegradation, demonstrating a trade-off between performance and end-of-life sustainability. However, high production costs, feedstock heterogeneity, and limited industrial scalability remain major barriers to commercialization. Future research should therefore prioritize process optimization, techno-economic feasibility, and life-cycle performance.
The copolymers of stearyl methacrylate or stearyl acrylate with N-vinyl-2-pyrrolidone were obtained by Reversible addition-fragmentation chain-transfer polymerization (RAFT) in mild conditions. The performed analysis of molecular weight parameters has clearly shows that the presence of the RAFT agents allows to decrease molecular weight distribution of the sample. The formation of copolymers was proved via NMR method. The reactivity ratios of the monomers were calculated using Kelen-Tudos and Fineman-Ross methods. According to the obtained values the monomers have comparable activities leading to the formation of uniform macromolecules. The obtained copolymers were tested as additives to hydrotreated diesel fuels. It was found that such polymers are capable to improve cold flow properties of fuel, such as cold filter plugging point, pour point and cloud point. The advantage of the proposed additives is their ability to increase of thermal oxidative stability of fuel. The obtained results allow considering the obtained copolymers as a base for complex additive with high performance.
Waste and residual biomass from agro- and food-processing represent vast, underexplored sources of biopolymers and active components for innovative packaging systems. In this context, this review highlights various polymer matrices derived from natural biomass, and the potential natural bioactives and pigments that have been found instrumental in the development of active and intelligent packaging systems (AIPs). To provide a data-driven perspective, the review incorporates bibliometric analysis using VOSviewer to map global research trends; Google-patent-driven patent analysis to highlight innovations and commercialisation opportunities; and PRISMA-based systematic analysis of recent literature. Bibliographic data revealed a total of 74 works on AIPs, 93
Abstract Epoxy-based nanocomposites filled with two-dimensional materials such as graphene nanoplates (GNP), graphene oxide (GO), and molybdenum disulfide (MoS₂) are widely investigated for electromagnetic applications, including electromagnetic interference (EMI) shielding. In this work, epoxy nanocomposites containing 0–5 wt% of different 2D fillers were prepared and their complex dielectric permittivity was measured by a coaxial transmission/reflection method using a vector network analyzer. Particular attention is devoted to the experimental reliability of the extracted electromagnetic parameters and to the influence of environmental factors. While permittivity values significantly higher than literature benchmarks were measured, no systematic dependence on filler concentration was observed. A detailed analysis indicates that moisture absorption in the epoxy system, combined with experimental limitations inherent to broadband coaxial measurements, can dominate the dielectric response and mask filler-dependent trends. Focusing on the frequency range up to 5 GHz, where the measurements are most stable, the experimental results are shown to be consistent with a simple effective-medium model that includes a third phase associated with absorbed water. The estimated moisture content required to account for the observed permittivity enhancement is on the order of 10 wt%. These findings highlight the critical role of moisture control and measurement setup in the electromagnetic characterization of epoxy-based nanocomposites and provide cautionary guidelines for the interpretation of permittivity data and their use in EMI shielding assessment.
