Resumo em Inglês:

Abstract Natural fibers have attracted growing attention due to their sustainability, low cost, and low density, yet their hydrophilic nature limits compatibility with polymer matrices and constrains broader applications. To overcome this challenge, diverse surface modification techniques-including chemical, enzymatic, and physical treatments- have been developed to improve fiber–matrix interfacial adhesion. These modifications are crucial for significantly enhancing the mechanical performance and environmental robustness of the resulting composite materials.This review critically evaluates established and emerging strategies, highlighting their effectiveness, advantages, and limitations. Among the various approaches, alkali treatment remains the most widely adopted, demonstrating consistent improvements in composite performance through impurity removal, enhanced surface roughness, improved fiber–matrix adhesion, and superior load transfer capabilities.

Resumo em Inglês:

Abstract Biomaterials engineering has evolved rapidly, with a particular emphasis on biofunctionalized hydrogels for tissue repair. This systematic review, based on PRISMA 2020 guidelines, analyzed 75 studies from the SCOPUS database, evaluating biopolymers combined with bioextracts for wound healing. Bibliometric analysis revealed a significant increase in publications from 2022 onward, with a focus on Biomaterials Engineering and Biotechnology. The most productive centers were the departments of Medical Nanotechnology, Biotechnology, and Biomedical Engineering. Among the central authors, Li, Doostan, and Karamanlioglu stood out. The most cited articles focused on antimicrobial and regenerative strategies. China leads in scientific production, followed by India and the USA. The most frequent keywords included “wound healing,” “hydrogel,” and “biocompatibility.” In vitro studies (53%) and combined in vitro/in vivo studies (43%) predominated. It is concluded that biofunctionalized hydrogels hold high therapeutic potential but require methodological standardization and clinical validation for safe application in regenerative medicine.

Resumo em Inglês:

Abstract In this study, different polymer systems, including polycarbonate (PC) and polyethylene-co-vinyl acetate (EVA) formulations, were exposed to gamma radiation. Spectroscopic analysis using FTIR revealed that these polymers retained their functional groups even after high doses of radiation. However, UV-Vis analysis indicated that gamma irradiation caused a significant increase in the yellowing and darkening index of standard PC, attributed to the formation of radiolytic species. The presence of radiostabilizing compounds reduced these effects on optical properties by 45%. Thermogravimetric analysis was conducted to determine parameters for thermal degradation and the activation energy of PC and EVA, showing that gamma irradiation could impact the kinetics of pyrolysis reactions in polymer systems.

Resumo em Inglês:

Abstract This study explored Ecovio®-based filaments and 3D-printed membranes functionalized with zinc oxide (ZnO), biocide (BCD), and carnauba wax (CW) for gravity-driven oil–water separation. Filaments and membranes were produced via fused filament fabrication in grid and triangular geometries and characterized through melt flow index, water absorption, optical microscopy, contact angle, and separation performance. ZnO increased melt flow and long-term water absorption, whereas CW reduced water absorption and increased surface hydrophobicity. Optical microscopy revealed composition-dependent pore architectures ranging from ≈ 355 to 668 µm, directly affecting permeation behavior. Membranes delivered high permeation fluxes, exceeding 1.10 × 107 L·m−2·h−1 under gravity-driven operation. The integrated results showed that tailored filler combinations and infill geometries enable tunable hydrophilicity, porosity, and flux, establishing Ecovio® composites as a sustainable and viable platform for additive manufacturing of oil–water separation membranes.

Resumo em Inglês:

Abstract In this work the effect of pultrusion process variables i.e. pultrusion die temperature, speed of pulling, and % of a hybrid bio filler (calcium carbonate (CaCO3), bagasse fiber, and carbon black (CB)) on the characteristics of pultruded glass fiber reinforced polymer (GFRP) composites is discussed. The response parameters, namely ultimate tensile and flexural strength, hardness, and % shrinkage were analyzed to realize the effect of pultrusion process parameters. A Taguchi L9 orthogonal array was used for single response optimization, and gray relational analysis for multi-response optimization. Results show that pultruded GFRP properties are significantly influenced and improved by optimizing the selected process parameters. An improvement of 31%, 6.5%, and 14.6% is achieved in ultimate tensile strength, flexural strength, and hardness respectively in comparison to result reported in earlier work by the authors. Results show that process optimization effectively enhances the performance, making them suitable for lightweight forearm protection applications.

Resumo em Inglês:

Abstract We developed a new type of nano-modified two-component waterborne polyurethane(2K WPU)coating using a regular structure of nano-silica: methyl-polyhedral oligomeric silsesquioxane (POSS) as a modified material. The POSS regular cage structure is used to improve the hardness and wear resistance that waterborne polyurethane lacks, maintain its good water resistance and heat resistance, and does not contain a benzene ring structure in the coating, eliminating the hidden danger of yellowing of the original benzene ring-containing 2K WPU hardening coating. The coating was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, contact angle measurement, UV-visible spectroscopy, water absorption test, hardness test, and anti-graffiti test. The evaluation results show that the modified coating has improved water resistance, hardness and contact angle, has excellent UV resistance, and has excellent anti-graffiti performance.

Resumo em Inglês:

Abstract This study examines Agave vilmoriniana leaf fibers after consecutive alkali, silane, and starch treatments for polymer composites. The treatments reduces hemicellulose, moisture absorption and improving fiber stability. X-ray diffraction Analysis showed intensified (002) peaks that confirming improved crystalline ordering, while Fourier Transform Infrared spectra showed the reduction of hemicellulose and lignin and after alkali and silane treatments by the peaks around 1730cm−1 band and the peak 750cm−1 confirms the emergence of siloxane linkages. Subsequently, thermal analysis using Thermogravimetry showed improved thermal stability with onset and maximum degradation temperatures were rising from ~285 to 305 °C and ~340 to 355 °C respectively. Mechanical testing shows starch coating increases stiffness to 23.42 GPa. Scanning Electron Microscopic image observations confirmed the gradual surface modifications. The result makes that the fibers were more suitable for high-performance, moisture-resistant and polymer composites.

Resumo em Inglês:

Abstract Responding to the growing interest in lignocellulosic materials for 3D printing, this research addresses the need for sustainable solutions, employing Amazonian wood waste and Brazil nut oil (BNO) as a natural binder for polylactic acid (PLA). We successfully developed filaments from a composition of 4% powdered sawdust of Nectandra rubra and Zygia racemosa, respectively with medium and high density, with 91% PLA and 5% BNO, which were extruded and printed. Physical-mechanical and characterization tests were performed using SEM, TGA, and FTIR. The incorporation of wood increased flexural strength, but reduced compression and tensile strength. FTIR analysis showed compatibility between the components, although the addition of wood caused agglomeration as indicated by SEM. The high-density species increased the thermal stability, as indicated by TGA. This study confirms the potential of filament developed with Amazonian woods and BNO, opening new avenues for sustainable additive manufacturing.

Resumo em Inglês:

Abstract Solid-phase extraction is an efficient strategy for preconcentrating several analytes. Studies of the relationship between the monomeric composition of polymers and sorption capacity of polycyclic aromatic hydrocarbons (PAHs) need to be expanded, seeking to contribute to the identification of the most suitable polymers for preconcentrating this pollutant. We selected crosslinked polymers with different monomer compositions for this study. These polymers were prepared by combining divinylbenzene or ethylene glycol dimethacrylate, with several comonomers. The polymers crosslinked with DVB had higher removal efficiency than those crosslinked with EGDMA. At equilibrium, the amount of phenanthrene adsorbed was 0.314 mg g−1 for poly(DVB) and 0.271 mg g−1 for poly(Sty-co-DVB). Poly(DVB) demonstrated a working capacity of 0.152 g cm-3. Notably, complete removal of phenanthrene from the aqueous leachate of drill cuttings was achieved using poly(DVB), indicating that this contaminant was effectively retained by the solid-phase extraction (SPE) column utilizing this polymer.

Resumo em Inglês:

Abstract The manufacture and industrial use of dyes generate highly colored, often non-biodegradable effluents that pose serious environmental and public health risks.The aim of this study was to evaluate the capacity of ferula stems from the Saida region to serve as a biosorbent in the treatment of water synthetically contaminated with two dyes, Congo Red (CR) and Methylene Blue (MB). The results of XRD, FTIR, SEM, and EDS analyses confirm that ferula stems biomass has an amorphous lignocellulosic structure with functional groups and surface characteristics that favor dye adsorption. MB shows a higher adsorption capacity than CR, with a maximum retention of 33.83 mg/g versus 21.0 mg/g for CR. In competitive adsorption, the biomass showed a greater affinity for MB with 85% at higher concentrations. Adsorption data were well described by the Langmuir isotherm (R2 ≈ 0.95). These results demonstrate the promising applicability of Ferula biomass for treating dye-contaminated waters.

Resumo em Inglês:

Abstract Biodegradable food packaging comprises plastic materials that decompose in the appropriate environment (e.g., moisture and temperature). It could represent a solution for micro- and macroplastic generation. This paper is the first to evaluate the addition of oat oil (OO) to PLA for use as a food packaging material. Samples were evaluated by FTIR, SEM, XRD, Raman, texture and degradation tests. The PLA crystallites and the porosity of the samples increased with increasing oat oil content, while strength decreased (0.14MPa). Regarding degradation, oat oil in the samples facilitated it. Samples with the same composition degraded more in soil (15 weeks) than in seawater (25 weeks). After degradation, the PLA-OO samples were porous, facilitating the entry of fluids and the adhesion of microorganisms. PLA matrix degradation in soil begins with hydrolysis, followed by aerobic microorganisms’ degradation. The highest biodegradation occurred in the PLA-1500 sample in soil, suggesting the potential to achieve biodegradability/compostability.

Resumo em Inglês:

Abstract This study presents a novel glycerol-based polymeric material doped with 0.12% (w/w) copper (II) sulfate pentahydrate for high-dose gamma dosimetry. Upon irradiation with doses ranging from 10 to 250 kGy using a Cobalt-60 source, the initially greenish material exhibited a progressive color change from yellow to dark red. Two analytical approaches were employed to evaluate the dosimetric potential: UV-Vis spectrophotometry, which demonstrated an exponential increase in absorbance at 456 nm up to 70 kGy, and digital image analysis using ImageJ, which extended the useful dose range to 250 kGy through measurements of green channel optical measurements. Both methods yielded reproducible calibration curves, highlighting the material’s potential as a low-cost, easy-to-handle dosimeter. This short communication reports preliminary findings that support further investigation into the material’s dosimetric mechanisms and optimization.