Polymers最新文献

{"title":"Density-Based Topology-Optimized 3D-Printed Fixtures for Cyclic Mechanical Testing of Lattice Structures.","authors":"Josué Castro, Rodrigo Valle, Jorge Leiva, Angelo Oñate, Enrico Saggionetto, Anne Mertens, Víctor Tuninetti","doi":"10.3390/polym17182468","DOIUrl":"10.3390/polym17182468","url":null,"abstract":"<p><p>The reliable experimental characterization of architected lattice materials under cyclic loading requires accurate fixture systems that ensure proper load transfer without introducing parasitic effects. This study presents the design and validation of testing fixtures optimized using density-based topological optimization techniques for performing cyclic load tests on lattice structures. The supports were manufactured with PLA filaments and evaluated using finite element simulation and experimental testing. The results show that the final design achieved a safety factor of 4.25, significantly improving on the initial value of 2.08. Likewise, the optimized supports showed reduced deformations by around 80% compared to the machine clamps, ensuring rigid and reliable stress transfer. In particular, while the metal structure of the test system showed deformations of several millimeters, the optimized PLA supports recorded displacements around 0.73 mm, confirming that they remain virtually rigid and ensure correct transmission of forces to the Kelvin-type structure. These findings confirm the viability of using PLA as an alternative to conventional metal devices in fixtures for mechanical testing of lattice materials.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473619/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation-Based Analysis and Optimization of High-Performance Dielectric Strength Polymers in the Injection Molding of Electrical Connectors.","authors":"Fuat Tan","doi":"10.3390/polym17182465","DOIUrl":"10.3390/polym17182465","url":null,"abstract":"<p><p>In this research, the thermal and structural responses of high-performance dielectric strength polymers in the injection molding process for multi-pin electrical connectors were thoroughly studied using Moldflow simulations and optimized via a Box-Behnken experimental design under the Response Surface Methodology (RSM). Injection molding analyses were performed on Polyether-ether-ketone (PEEK), Polyetherimide (PEI), and Polyamide-imide (PAI) polymers using the MS3102A 16S-1P electrical connector model. In the conducted simulations, the melt temperature, injection time, and mold open time were evaluated as three fundamental process parameters through multivariate analysis. The volumetric shrinkage, sink mark depth, residual stress, warpage, and surface temperature homogeneity were considered as the major output qualities. According to the results, the PAI material provided superior thermal stability with an average heat removal capacity of 0.127 kW, whereas the PEI material exhibited the most homogeneous cooling behavior with a surface temperature of 45.5 °C. The minimum warpage was found to be 0.254 mm, whereas the sink mark depth was recorded within the range of 0.018-0.031 mm and the rate of volume shrinkage was between 1.03% and 1.41% in the investigations. The PAI material gave the maximum residual stress of 81.9 MPa in oriented regions of the mold. This study fills a considerable gap in the field by investigating material choice and process parameter adjustments via multivariate analysis, particularly for decision making in the production of high-reliability electrical components.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473634/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-Component Response Regulators CitT, YvcP, and YycI Differentially Control Pectin and Hemicellulose Degradation in Degumming of Ramie Fibers by <i>Bacillus subtilis</i> Strain 168.","authors":"Qi Yang, Shihang Ma, Lifeng Cheng, Xiang Zhou, Guoguo Xi, Chen Chen, Zhenghong Peng, Yuqin Hu, Si Tan, Shengwen Duan","doi":"10.3390/polym17182473","DOIUrl":"10.3390/polym17182473","url":null,"abstract":"<p><p>Exploring the metabolic regulatory mechanisms of bacteria for ramie degumming and constructing more efficient engineered strains are preferred strategies to solve the technical bottleneck of high residual gum content in fibers. <i>Bacillus subtilis</i> strain 168, an advantageous bacterium for microbial degumming, was previously found to significantly up-regulate the expression of bast two-component system (TCS) response regulators CitT, YvcP, and YycI when using ramie as the sole carbon source. In this study, the genes encoding CitT, YvcP, and YycI proteins were knocked out and compared the effects between these gene knockouts and the original strain on the degumming efficiency. The aim was to identify the key TCS response regulators that significantly affect degumming efficiency and to explore the functions of these different response regulators. The results demonstrated that knockout of <i>citT</i>, <i>yvcP</i>, or <i>yycI</i> genes significantly reduced degumming efficiency. Specifically, CitT protein primarily regulated the degradation of pectin, YvcP protein mainly regulated the degradation of hemicellulose, and YycI protein was involved in the regulation of both pectin and hemicellulose degradation. Notably, the absence of CitT protein caused the most significant reduction in degumming efficiency. These findings provide valuable insights into the construction of engineered strains with high degumming efficiency for ramie fibers.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473414/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inhibition of <i>Pseudomonas aeruginosa</i> Biofilms Using Robust Silk Fibroin-Poly(ethyleneimine) Microparticles.","authors":"Grace Neven, Tippabattini Jayaramudu, Mingyang Mao, Tugba Ozdemir","doi":"10.3390/polym17182470","DOIUrl":"10.3390/polym17182470","url":null,"abstract":"<p><p>Controlling bacterial growth and biofilm formation remains a major challenge in the treatment of chronic wounds and in preventing infection after biomedical device implantation. Thus, creating materials with inherent antibacterial potential is necessary. Here, we report silk fibroin-polyethylenimine-based (SF-PEI) microparticles to control the growth of <i>Pseudomonas aeruginosa</i>, which is a highly infectious and biofilm-forming pathogen. SF-PEI microparticles were fabricated using a solvent displacement method, and their microparticle formation was confirmed using Fourier-transform infrared spectroscopy (FTIR). The morphology and size of the microparticles were characterized using scanning electron microscopy (SEM) and dynamic light scattering (DLS). The SEM and DLS methods revealed that the microparticles formed showed a uniform, spherical morphology with a consistent size distribution, showing a Z-average of 834.82 nm. The antibacterial and biofilm inhibition properties of the SF-PEI microparticles were tested against <i>P. aeruginosa</i>. The results show significant control of bacterial growth and biofilm formation when treated with the SF-PEI particles. Further, a cell viability assay was evaluated using human dermal fibroblasts, and the results demonstrated that the SF-PEI microparticles developed demonstrated cytocompatibility, with no significant cytotoxic effects observed. These results suggest that SF-PEI microparticles offer a promising biocompatible strategy for reducing bacterial growth and their biofilm-associated infections, particularly in wound healing and medical device applications.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473277/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of Textile Dye Mixture by Fe₃O₄/Acrylamide/Triacryloylhexahydro Triazine Composite Hydrogel Polymer.","authors":"Sude Sena Erdağı, Can Serkan Keskin, Semra Yılmazer Keskin, Ayşe Avcı","doi":"10.3390/polym17182469","DOIUrl":"10.3390/polym17182469","url":null,"abstract":"<p><p>A swellable magnetic polymer with high removal capacity was produced. The copolymer consisting of acrylamide and 2,4,6-triallyloxy-1,3,5-triazine was synthesized via the radical polymerization method. Previously prepared magnetic Fe₃O₄ particles with the co-precipitation method were added during the synthesis, and then the obtained composite was hydrolyzed. The composite became a swellable hydrogel after hydrolysis. The synthesized magnetic composite hydrogel polymer was used for Malachite Green (MG) and Acid Violet 19 (AV19) binary textile dye mixture removal. A derivative method was developed to calculate the individual concentration of dyes in mixture solutions. The accuracy and precision of the developed method were examined by calculating the recovery percentage (R%) and relative standard deviation (RSD%). The highest removal percentages (~99% for MG and ~100% for AV19) were achieved at the dye mixture's natural pH (pH 4). Antibacterial tests were examined against Gram-negative and Gram-positive bacteria, and the synthesized composite hydrogel polymer showed higher activity. The FTIR, XRD, SEM, and EDS analyses were also performed to characterize the synthesized materials.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473609/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Doping of PDMS-NQS Sensors to Modify Their Response and Sustainability: Ammonia Quantitation in Farm Atmospheres as a Case Study.","authors":"Belén Monforte-Gómez, Camila Soto, Pilar Campíns-Falcó","doi":"10.3390/polym17182466","DOIUrl":"10.3390/polym17182466","url":null,"abstract":"<p><p>In this work, different passive solid composites of 1,2-naphthoquinone-4-sulfonic acid sodium salt (NQS) embedded in polydimethylsiloxane (PDMS) and tetraorthoethylsilicate (TEOS) doped with silica nanoparticles (SiO₂NPs) were obtained. New composites including deep eutectic solvent (DES) and choline chloride (ChCl) were synthetized and compared here vs. ionic liquid (IL) which was previously proposed, from their passive response with time. Monitoring and controlling of ammonia levels inside poultry and rabbit farming facilities are essential for animal welfare, workers' exposure assessment, and measurement of environmental emissions. Real poultry and rabbit farm atmosphere samples were analyzed at different sensor exposition times, obtaining results between two and eight ppmv of NH₃ in all cases. The results were compared by air sampling with Tedlar bags and analysis by UHPLC-QTOF from a miniaturized SPE supported derivatization that was developed. As primary amine group NH₃ was the major component in the farm atmosphere, the presence of methylamine was negligible. PDMS-based sensors with DES or ChCl add new potential for previously developed composites, improving the versatility for controlling ammonia by using new sustainable composites with different time responses.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473573/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Performance Evolution and Elasto-Plastic Damage Modeling of Basalt Fiber-Reinforced EPS Geopolymer Lightweight Concrete.","authors":"Feng Liang, Qingshun Yang, Jutao Tao","doi":"10.3390/polym17182471","DOIUrl":"10.3390/polym17182471","url":null,"abstract":"<p><p>To elucidate the multi-performance evolution mechanisms of basalt fiber-reinforced lightweight expanded polystyrene geopolymer concrete (LEGC), a two-tiered investigation was conducted. In the first part, a series of LEGC mixtures with varying volume fractions of EPS (10-40%) and basalt fiber (BF) (0.4-0.8%) were designed. Experimental tests were carried out to evaluate density, flowability, compressive strength, flexural strength, and splitting tensile strength. Crack propagation behavior was monitored using DIC-3D speckle imaging. Additionally, X-ray CT scanning revealed the internal clustering of EPS particles, porosity distribution, and crack connectivity within LEGC specimens, while SEM analysis confirmed the bridging effect of basalt fibers and the presence of dense matrix regions. These microstructural observations verified the consistency between the synergistic effects of EPS weakening and fiber reinforcement at the microscale and the macroscopic failure behavior. The results indicated that increasing EPS content led to reduced mechanical strength, whereas the reinforcing effect of basalt fiber followed a rising-then-falling trend. Among all specimens, LEGC20BF06 exhibited the best comprehensive performance, achieving a compressive strength of 40.87 MPa and a density of 1747.6 kg/m³, thus meeting the criteria for structural lightweight concrete. In the second part, based on the experimental data, predictive models were developed for splitting tensile and flexural strengths using compressive strength as a reference, as well as a dual-factor model incorporating EPS and fiber contents. Both models were validated and demonstrated high predictive accuracy. Furthermore, a splitting tensile elasto-plastic damage constitutive model was proposed based on composite mechanics and energy dissipation theory. The model showed excellent agreement with experimental stress-strain curves, with all fitting coefficients of determination (R²) exceeding 0.95. These findings offer robust theoretical support for the performance optimization of LEGC and its application in green construction and prefabricated structural systems.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473786/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The State of the Art and Innovations in Active and Edible Coatings and Films for Functional Food Applications.","authors":"Sandra Mariño-Cortegoso, Antía Lestido-Cardama, Raquel Sendón, Ana Rodríguez Bernaldo de Quirós, Letricia Barbosa-Pereira","doi":"10.3390/polym17182472","DOIUrl":"10.3390/polym17182472","url":null,"abstract":"<p><p>Edible coatings and films are gaining the attention of researchers, consumers, and the food industry as a sustainable alternative to conventional plastic packaging. This review provides an overview of recent advances in their development, with a particular focus on new natural sources of biomaterials (e.g., proteins and polysaccharides) and natural additives (antioxidants and antimicrobials). Special attention is given to high-technology preparation methods, including electrohydrodynamic atomization (EHDA), as well as controlled release systems for bioactive compounds designed to preserve foodstuffs and extended their shelf life. The application of edible coatings as carriers of nutrients (vitamins) and bioactives (probiotics and polyphenols) to improve the nutritional value and support the development of functional foods is also discussed. In addition, this review addresses safety considerations and regulatory aspects that are crucial for commercialization and consumer acceptance. Finally, key challenges are highlighted, including the improvement of mechanical and barrier properties, scalability of innovative technologies, consumer education, regulatory support, and the integration of circular economy principles, to encourage the adoption of these sustainable solutions.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473381/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Durability of Basalt- and Glass Fiber-Reinforced Polymers: Influence of Internal Stresses, Mass Loss Modeling, and Mechanical/Thermomechanical Properties Under Extreme Cold Climate Exposure.","authors":"Anatoly K Kychkin, Oleg V Startsev, Mikhail P Lebedev, Anatoly S Krotov, Aisen A Kychkin, Anna A Gavrilieva","doi":"10.3390/polym17182457","DOIUrl":"10.3390/polym17182457","url":null,"abstract":"<p><p>The durability of basalt fiber-reinforced polymer (BFRP) and glass fiber-reinforced polymer (GFRP) composites was evaluated under extreme cold conditions in Yakutsk (-54 to +36 °C. Laminates (18 layers, epoxy CYD-128) were exposed outdoors for three years. Mechanical testing showed tensile strength and modulus reductions of 22-32% for GFRP, compared with only 6-12% for BFRP. Dynamic mechanical analysis indicated that the glass transition temperature decreased by 11-14 °C in GFRP and 4-6 °C in BFRP. Mass loss kinetics were studied on specimens of different sizes (10 × 10, 20 × 20, and 40 × 40 mm) over 405 days. Seasonal sorption ranged between 0.01-0.19%, while long-term degradation followed a Fickian law with diffusion coefficients of degradation products from 1×10-4 to 0.29mm2/day. A diffusion-based model was proposed, where total mass change is represented as the superposition of reversible sorption and irreversible degradation. The model accurately reproduced experimental trends, highlighting the higher resistance of BFRP. Surface morphology analysis revealed matrix erosion and microcracking on exposed surfaces, with average roughness increasing from 1.61-5.61 µm to 5.86-11.73 µm. Thermomechanical analysis confirmed that BFRP maintained more stable coefficients of linear thermal expansion (-60 to 100 °C) than GFRP, reducing thermally induced stresses during seasonal cycles. These findings demonstrate the superior stability of BFRP compared with GFRP under cold-climate exposure. Comparison of experimental results with mathematical modeling demonstrated that the primary cause of polymer matrix degradation is the action of abrupt internal stresses arising during thermal cycling under extreme cold climate conditions.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473502/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermo-Compression of Thermoplastic Chitosan Films Reinforced with Microcrystalline Cellulose for Antibacterial Food Packaging Application.","authors":"Prasong Srihanam, Theeraphol Phromsopha, Aphidech Sangdee, Nuanchai Khotsaeng, Pham Ngoc Lan, Yodthong Baimark","doi":"10.3390/polym17182460","DOIUrl":"10.3390/polym17182460","url":null,"abstract":"<p><p>Thermoplastic chitosan/microcrystalline cellulose (TPC/MCC) composite films were prepared by thermo-compression and are reported here for the first time. L-lactic acid (LLA) was used as a plasticizer in the formation of TPC. TPC films with varying LLA contents and the TPC/MCC composite films with different MCC contents were produced for evaluation. The physicochemical, mechanical, and antibacterial properties of the thermo-compressed TPC and TPC/MCC films were characterized. LLA enhanced thermal stability and crystallinity, improved film flexibility, and reduced the water solubility of the chitosan matrix. Incorporation of MCC further improved mechanical properties and decreased water dissolution. Tensile testing showed that the addition of 5 wt% MCC increased maximum tensile strength by 82% and Young's modulus by 124%. All TPC and TPC/MCC films exhibited antibacterial activities against both Gram-positive <i>Staphylococcus aureus</i> and Gram-negative <i>Escherichia coli</i>. Antibacterial efficacy decreased as MCC content increased to 20 wt%. These thermo-compressed TPC/MCC films can be tailored to display a range of properties by adjusting the contents of LLA and MCC, making them well suited for antibacterial food-packaging applications.</p>","PeriodicalId":20416,"journal":{"name":"Polymers","volume":"17 18","pages":""},"PeriodicalIF":4.9,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12473501/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145177814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}