Search Results (976)

Background/Objectives: Wettability is a key surface property of denture base resins and is related to denture retention through interfacial cohesive–adhesive forces; conversely, compromised material wettability facilitates bacterial adhesion and colonization. Although three-dimensional (3D) printing has become an increasingly popular method for fabricating dentures, there is insufficient evidence regarding the wettability of 3D-printed denture base resins. This study aims to evaluate the wettability of 3D-printed, heat-polymerized, and milled denture base resins by comparing their contact angles. Methods: A search was conducted in MEDLINE, Scopus, and Web of Science, while grey literature was also assessed. The risk of bias was evaluated using the Quality Assessment Tool for In Vitro Studies (QUIN). Meta-analyses were conducted using inverse variance and the random effects model. Results: A total of nine and seven studies were included in the quantitative synthesis comparing 3D-printed denture base resins with heat-polymerized and milled resins, respectively. A statistically significant difference of −6.50 degrees was observed in favor of 3D-printed denture base resins compared to heat-polymerized ones (95% CI: −12.11 to −0.90, I² = 99%), while the comparison between 3D-printed and milled resins showed a non-statistically significant mean difference (MD: 0.87, 95% CI: −5.08 to 6.82, I² = 98%). Conclusions: The available in vitro evidence indicates that 3D-printed denture base resins tend to exhibit improved surface wettability compared with heat-polymerized resins and perform similarly to milled resins. However, given the extremely high heterogeneity, these findings should be interpreted with caution, as clinical performance depends on the complex interplay between surface characteristics and microbial adhesion rather than solely on wettability. Full article

Conventional flexible substrates for strain sensors generally exhibit good flexibility and processability; however, their limited heat resistance restricts their long-term application in high-temperature environments. Aiming at the problem of insufficient heat resistance of high-temperature flexible strain sensing matrix, triphenyltetramethylcyclotrisiloxane (P₃), trimethyltrivinylcyclotrisiloxane (V₃) and octamethylcyclotetrasiloxane (D₄) were used as raw materials in this paper. Methyl vinyl phenyl silica gel (MVMPS) with high phenyl and vinyl content was prepared by anionic ring-opening polymerization, and condensed with KH-570 (3-Methacryloxypropyltrimethoxysilane) to obtain a condensed modified gel (C-MVMPS). Subsequently, a methyl vinyl phenyl silicone rubber composite was fabricated using fumed silica as the reinforcing filler and Si69 as the coupling agent and vulcanization assistant. In addition, flake silver powder was incorporated to prepare an Ag/MVMPS conductive adhesive, and a sandwich-structured strain sensor with a silicone rubber/Ag-MVMPS conductive adhesive/silicone rubber configuration was fabricated. The synthesized methyl vinyl monophenyl silicone gum exhibited a number-average molecular weight of 170,449, a phenyl content of 25.19%, and a vinyl content of 24.44%. The composite showed the best overall performance at 3 phr (parts per hundred of rubber) Si69 (Bis(gamma-triethoxysilylpropyl) tetrasulfide) and 30 phr SiO₂ (Fumed silica), with a 5% weight-loss temperature (T_5%) of 367.14 °C and a 10% weight-loss temperature (T_10%) of 529.6 °C. The prepared sandwich-structured sensor exhibited clear and stable resistance responses within the strain range of 10–80%. The sensitivity increased with increasing strain, and good reproducibility was maintained under different loading rates. Moreover, the sensor still exhibited continuous and distinguishable cyclic responses after 1000 cycles at 20% strain. These results provide an experimental basis and a feasible design strategy for the application of methyl vinyl phenyl silicone rubber in high-temperature flexible strain sensors. Full article

Background/Objectives: Denture stomatitis is closely associated with Candida albicans colonization of denture-base surfaces. This in vitro study compared early adhesion (1 h) and initial biofilm formation (24 h) of C. albicans across five denture-base-related material groups using adhered cell counts and adhered/inoculum proportions. Methods: A 5 × 2 factorial design (five material groups; 1 and 24 h) evaluated a comparator pattern resin, heat-polymerized acrylic resin, autopolymerizing acrylic resin, milled CAD/CAM PMMA, and microwave-polymerized acrylic resin. All specimens underwent standardized finishing and mechanical polishing before microbiological testing. Data were log10-transformed and analyzed by two-way ANOVA (material group, time) with Tukey’s post hoc test. An external SEM-based qualitative laboratory report was used as complementary documentation of C. albicans presence after 1 h and 24 h; representative micrographs and quantitative SEM image outputs were unavailable. Results: Material group, time, and their interaction significantly affected adhered C. albicans counts (p < 0.05). At 1 h, the comparator pattern resin showed the highest adhesion, whereas at 24 h, milled CAD/CAM PMMA showed the highest adhered load. For the adhered/inoculum fraction, both material group and time were significant; at 24 h, the heat-polymerized acrylic resin showed the lowest adhered fraction. Conclusions: Under the standardized finishing and mechanical polishing conditions of this in vitro model, the tested material groups showed different C. albicans adhesion/biofilm patterns over time; clinical extrapolation should be made with caution. Full article

Paraffins are attractive as phase-change materials (PCMs) due to their high latent heat capacity and adjustable phase transition temperatures. However, the individual high-purity paraffins, especially the long-chain ones, are labor-intensive and costly to produce and capable of storing and releasing latent heat only within a limited temperature range. Herein, we demonstrate the feasibility of a high-purity paraffin wax fraction (C13–C49) obtained via the Fischer–Tropsch (FT) process as a versatile latent heat storage additive within a wide range of phase transition temperatures (8.1–98.2 °C). To avoid the leakage, the FT wax was encapsulated via nanoemulsion interfacial polymerization of melamine formaldehyde (MF) shells with various core-to-monomer and melamine/formaldehyde ratios. Differential scanning calorimetry revealed that the latent heat storage capacity of the FT/MF capsules was 104.5–163.4 J/g depending on the FT loading efficiency, with the heat storage and release range of −0.7–100.2 °C and −9.8–85.8 °C, respectively. The capsules were tested as a thermoregulating additive to commercially available gypsum plaster. Unlike employment of the additives based on individual paraffins, the addition of FT/MF capsules led to a smooth reduction in heating/cooling rates of plaster layers in an extended temperature range. This makes FT/MF capsules a promising and versatile additive for a diversity of thermal energy storage applications. Full article

Three crosslinked polyurethane copolymers were successfully synthesized as polymeric solid–solid phase change materials (SSPCMs) for thermal energy storage. These materials were fabricated utilizing trihydroxy compounds (glycerol, triethanolamine, and trimethylolethane) as chain extenders and polyethylene glycol (PEG) as the phase change functional segment. A comprehensive suite of characterization techniques was employed to investigate the chemical structures, thermal properties, and crystalline behaviors of the resulting SSPCMs. Fourier transform infrared (FTIR) spectroscopy confirmed the successful synthesis of the crosslinked polyurethane network. Polarizing optical microscopy (POM) and wide-angle X-ray diffraction (WAXD) analyses revealed that all three SSPCMs exhibit regular spherulitic morphologies with sharp diffraction peaks resembling those of pure PEG, although variations in spherulite size and diffraction intensity were observed among the samples. Differential scanning calorimetry (DSC) demonstrated the reversible latent heat storage and release capabilities of the synthesized SSPCMs, with a maximum endothermic enthalpy (ΔH_endo) of 115.7 J/g. Furthermore, thermal cycling tests and thermogravimetric (TG) analysis verified their exhibit excellent reusability, thermal reliability, and high thermal stability. Full article

Bio-based, biodegradable, and renewable polymers offer a promising alternative to traditional synthetic polymers derived from petroleum or other non-renewable resources. However, their use is limited by suboptimal properties and high costs. Incorporating sustainable reinforcements into the polymer matrix significantly improves biopolymer performance while preserving key properties, sustainability, and cost-effectiveness. Bio-based polymeric composites have emerged as a crucial category of biopolymers, playing a key role in advancing a sustainable, circular economy. This review provides an updated overview of bio-based polymer composites and nanocomposites, focusing on reinforcement strategies using natural nanofillers and engineered nanoparticles. We summarize key synthesis and processing methods, discuss structure–property relationships, and highlight recent advances in applications such as food packaging, biomedical devices, energy systems, environmental remediation, 3D printing, and supercapacitors. Polymer nanocomposites are versatile, with their performance depending on the type, size, and interactions between the fillers and the polymer matrix. Progress in metallic, ceramic, carbon-based, natural, and hybrid fillers has improved their properties. Using bio-based polymers and renewable fillers supports sustainability. Natural nanofillers derived from renewable sources and industrial byproducts offer a sustainable approach to developing high-performance, biodegradable nanocomposites. Smart nanocomposites can react to external stimuli by integrating specialized fillers that enhance their mechanical and mobility properties. Shape memory nanocomposites can be remotely activated—using heat, electricity, magnets, or light—enabling advanced applications. Finally, we address major challenges and outline future directions for scalable, circular-material solutions, drawing on perspectives from the circular economy and life cycle assessment (LCA). Full article

Polyphenols have attracted considerable scientific interest over recent years due to their broad spectrum of biological activities, including antioxidant, cardioprotective, anti-inflammatory, antidiabetic, and anticancer properties. However, their practical application is often limited by unfavorable physicochemical characteristics, particularly low aqueous solubility. Consequently, amorphous solid dispersions (ASDs) have been extensively investigated as a formulation strategy to overcome these limitations. This article represents the first part of a two-part review and presents the current state of the art in amorphous solid dispersions of polyphenols. The available literature is systematically summarized with respect to the investigated polyphenolic compounds, the employed carriers (with particular emphasis on polymeric systems), the preparation methods, and the solid-state characterization techniques used to confirm amorphization. Both single-component systems and binary combinations of polyphenols reported in the literature are considered. The collected data are presented in tabular form and complemented by a heat map illustrating the frequency of reported polyphenol–carrier combinations. The aim of this review is to organize the available knowledge, identify the most extensively studied systems, and highlight research areas that remain underexplored. A detailed discussion of the pharmaceutical benefits and mechanistic aspects of polyphenols in ASD systems will be provided in Part II. Full article

Sorghum (Sorghum bicolor L.) is an environmentally friendly crop known for its nutritional and bioactive properties. This study investigated the effects of sorghum on the antioxidant properties and consumer acceptance of nurungji, a traditional Korean snack. To understand the antioxidant contribution of ferulic acid in sorghum during non-enzymatic browning, the antioxidant activity of ferulic acid was evaluated using a sugar (glucose or fructose)–lysine Maillard reaction model system. Nurungji samples were prepared with varying sorghum blending ratios (SN0, SN25, SN50, SN75, and SN100) and heating durations (0, 1, 3, and 5 min). The total polyphenol and total flavonoid contents of nurungji increased significantly in a sorghum concentration- and heating duration-dependent manner. Antioxidant activities, including DPPH and ABTS radical scavenging activities, ferric reducing antioxidant power (FRAP), and reducing power, exhibited trends similar to those of the antioxidant components. In the isolated model system, the addition of ferulic acid significantly enhanced the antioxidant capacity of the Maillard reaction products (MRPs), with the fructose–lysine–ferulic acid solution exhibiting the highest activity. These results support the proposed mechanism that during the thermal processing of nurungji, complex polymeric phenolic compounds within the sorghum are degraded, releasing free ferulic acid that actively boosts the overall antioxidant properties of the resulting MRPs. Although the antioxidant properties of nurungji increased with higher sorghum concentration, the consumer acceptance evaluations indicated that SN0 and SN25 received significantly higher scores for overall acceptance, taste acceptance, and purchase intention (p < 0.05). Full article

Current strategies for treating organic dye wastewater are shifting from single-function removal processes and catalytic degradation methods toward more integrated treatment approaches. This study proposes a multifunctional composite integrating adsorption–photodegradation–intelligent recovery for photodegradation and recovery of methylene blue-contaminated wastewater. By optimizing the preparation process to precisely control the pore size and arrangement of the aerogel, a hierarchical porous framework with a high specific surface area is formed, featuring efficient mass transfer and ultra-multiple loading sites. The graphene framework enhances visible-light absorption by optimizing TiO₂ loading, agglomeration behavior and addressing detachable defects through a metal–polyphenol network. After 60 min of illumination, the degradation efficiency exceeds 99.5%, demonstrating superior cycling stability. After 100 cycles, the photocatalytic efficiency remains above 97%, showcasing excellent durability. Furthermore, the in situ polymerized thermoresponsive poly (N-isopropylacrylamide) (PNIPAm) composite exhibits smart responsiveness, enabling reversible temperature-responsive adsorption–desorption behavior within PNIPAm’s LCST range. with an adsorption capacity of 28,000 mg/g at LCST. Heating above LCST desorbs 90.2% of the wastewater, and adsorption stability remains above 98% after 100 thermal cycles, resolving operational challenges in mechanical wastewater recovery. The synergistic integration of an anisotropic porous structure, stable TiO₂ loading, and thermal responsiveness provides an efficient platform for integrated adsorption and recovery. Full article

Thermosensitive nanogels are highly sensitive to temperature fluctuations, making precise thermal control critical for uniform particle formation and consistent product quality. This study introduces a TRIZ-guided reactor design that integrates material-level self-feedback heating with structurally homogenized heat transfer, shifting temperature regulation from conventional multi-point feedback to intrinsic physical adaptation. Experimental evaluation demonstrated that the optimized system reduced the maximum temperature difference from 6.5 °C to 3.2 °C and decreased the standard deviation from 3.9 °C to 1.8 °C, resulting in improved reaction stability. Correspondingly, monomer conversion increased from 90% to 95%, and the particle size distribution narrowed, with PDI decreasing from 0.32 to 0.18. The energy consumption per unit mass of reactant also decreased from 3.6 kJ·g⁻¹ to 2.5 kJ·g⁻¹. These results indicate that the TRIZ-based self-feedback approach effectively enhances temperature uniformity, reaction control, and energy efficiency, providing a transferable strategy for temperature-sensitive polymerization and nanomaterial synthesis. Full article

This study aimed to investigate the effect of time and different disinfecting agents on nanocomposite filler composed of natural clay nanoparticles (modified and non-modified) added to maxillofacial silicone elastomers and readymade pigment additives. A total of 360 disk-shaped samples were divided into nine pigment-based groups, each with four subgroups (n = 10) exposed to different disinfectants: distilled water, 1% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), and effervescent tablets. Color changes (ΔE) were measured before and after disinfection using a colorimeter. The ΔE values were assessed against perceptibility (ΔE = 1.1) and acceptability (ΔE = 3) thresholds. Nanoclay additives were also characterized using FTIR, XRD and EDX. Statistical analysis, including ANOVA and post hoc HSD tests, revealed that while all samples exhibited some color change, most remained below the acceptability threshold. Colorless silicone showed minimal, non-significant change according to perceptibility threshold (ΔE = 1.1). Blue pigments displayed significant change only with effervescent tablets. Red and mixed pigments showed perceptible changes with NaOCl, CHX, and effervescent tablets. However, nanoclay-containing specimens showed no significant perceptible alterations. Overall, despite minor perceptible changes in some pigments, all disinfecting agents tested resulted in color differences below the acceptability threshold, indicating their safe use for disinfecting maxillofacial silicone materials without compromising esthetics. Nevertheless, nanoclays are more reliable agents for the pigmentation of maxillofacial silicone as they show non-significant chromatic alteration. Full article

The aqueous phase (AP) produced during hydrothermal liquefaction (HTL) contains high organic loads and a chemically complex mixture of dissolved intermediates, posing significant environmental management challenges. Aqueous phase recycling (APR) has emerged as a strategy to enhance bio-crude yield, improve energy recovery, and reduce freshwater consumption by reintroducing reactive water-soluble species into subsequent cycles. However, repeated recycling can lead to the accumulation of N-containing compounds and phenolics, potentially diminishing bio-crude quality and heating value through secondary polymerization and condensation reactions. Simultaneously, the carbon and nutrient-rich character of AP presents opportunities for valorization via anaerobic digestion, microalgae cultivation, and supercritical water gasification. Despite growing interest, APR-HTL research remains feedstock-specific, and a systematic understanding of AP compositional evolution across multiple recycling cycles is limited. This review synthesizes recent progress, highlighting mechanistic linkages between AP composition, bio-crude performance, and integrated biorefinery strategies. Full article

The increasing adoption of digital light processing (DLP) three-dimensional (3D) printing in prosthodontics has enabled the rapid fabrication of denture bases with improved dimensional accuracy and reproducibility. However, the mechanical performance and surface characteristics of 3D-printed denture base resins remain inferior to those of conventional heat-polymerized polymethyl methacrylate (PMMA), limiting their long-term clinical reliability. This study aimed to investigate the effect of incorporating zinc oxide (ZnO) and samarium oxide (Sm₂O₃) nanoparticles, individually and as hybrid nanofiller systems, on the mechanical and wettability properties of a DLP 3D-printed denture base resin. ZnO and Sm₂O₃ nanoparticles were incorporated into a photopolymerizable denture base resin at concentrations of 1 and 2 wt.%, producing seven experimental formulations, including a control group. A total of 280 specimens were fabricated using a DLP 3D printer and subjected to standardized post-processing. Nanoparticle dispersion and morphology were examined using field-emission scanning electron microscopy (FE-SEM), while Fourier-transform infrared spectroscopy (FTIR) was employed to assess possible chemical interactions between the nanofillers and the polymer matrix. Mechanical performance was evaluated through impact strength, transverse strength, and flexural strength tests, and surface wettability was assessed using static water contact angle measurements. Statistical analysis was conducted using one-way ANOVA followed by Tukey’s post hoc test (α = 0.05). The results demonstrated that all nanoparticle-reinforced groups exhibited significantly enhanced mechanical properties compared with the unmodified control resin. The incorporation of 1 wt.% nanofillers yielded the most pronounced improvements, with the 1 wt.% ZnO group achieving the highest transverse strength and the 1 wt.% ZnO–Sm₂O₃ hybrid group exhibiting the maximum flexural strength. Increasing the nanofiller concentration to 2 wt.% resulted in partial reductions in impact and flexural strength, which were attributed to nanoparticle agglomeration and increased light scattering during photopolymerization. FTIR analysis revealed no evidence of chemical bonding between the resin matrix and the nanofillers, indicating that the observed enhancements were primarily governed by physical reinforcement mechanisms. Wettability analysis showed that Sm₂O₃-containing formulations significantly reduced the water contact angle, indicating increased surface hydrophilicity, whereas ZnO incorporation produced more hydrophobic surfaces. Within the limitations of this in vitro study, the findings suggest that low-concentration incorporation of ZnO and Sm₂O₃ nanoparticles represents an effective strategy to enhance the mechanical integrity and tailor the surface properties of DLP 3D-printed denture base resins. These results suggest potential clinical relevance of nanoparticle-reinforced printed denture bases, emphasizing the importance of optimized filler loading to avoid agglomeration-induced performance degradation. Full article

Polydicyclopentadiene (PDCPD), an emerging environmentally friendly material, has been widely applied in lightweight structural shells; however, its extension to high-value electronic applications remains challenging. In this work, we developed a novel vinyl-SiO₂@NaNbO₃ (VSN) core–shell structure with a high surface vinyl concentration (1.26 mmol/g) and excellent thermal stability, making it highly suitable for co-polymerization with polymers. Through ring-opening metathesis polymerization, the influence of VSN on the mechanical, thermal, and dielectric properties of PDCPD composites was systematically investigated. The vinyl groups on the VSN surface provide strong interfacial compatibility with the PDCPD matrix. With only 1.0 wt% loading, the composites show significant performance improvements: the heat deflection temperature and glass transition temperature increased to 139.3 °C and 150.43 °C, respectively, while the dielectric constant at 1 kHz rises to 4.13 with an ultralow dielectric loss of 0.035%. Meanwhile, the composites maintain high mechanical strength and solvent resistance. This study not only establishes a facile strategy for fabricating highly compatible inorganic additives but also offers new opportunities for expanding PDCPD into advanced dielectric and electronic applications. Full article

The silkworm, Bombyx mori, is a model organism with significant agricultural and economic importance, but it is threatened by Bombyx mori nucleopolyhedrovirus (BmNPV). A crucial chaperone, heat shock protein 90 (HSP90), can also facilitate the proliferation of viruses, and our previous quantitative acetylome analysis revealed that lysines 550 and 567 in the carboxyl-terminal domain (CTD) of Bombyx mori HSP90 (BmHSP90) were significantly deacetylated following BmNPV infection, but the underlying mechanism remained unknown. In this study, deacetylation-mimetic (K to R) mutants of BmHSP90 exhibited increased dimerization and chaperone activity compared with the wild-type. In addition, the mutants also exhibited higher affinity for actin, promoting F-actin polymerization. Collectively, these changes facilitated BmNPV replication and progeny virion production. This study reveals that the deacetylation of BmHSP90 at K550 and K567 mediates crucial host–virus interactions, providing novel insights into potential antiviral strategies. Full article