You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.

Search for Articles:

Title / Keyword

Author / Affiliation / Email

Journal

Article Type

Advanced Search

Section

Special Issue

Volume

Issue

Number

Page

Logical OperatorOperator

Search Text

Search Type

Effect of Electron Beam Irradiation on the Percentage Loss of Tensile Modulus of Epoxy Polymer

Journal Description

Polymers

Polymers is an international, peer-reviewed, open access journal of polymer science published semimonthly online by MDPI. Belgian Polymer Group (BPG), European Colloid & Interface Society (ECIS), National Interuniversity Consortium of Materials Science and Technology (INSTM) and North American Thermal Analysis Society (NATAS) are affiliated with Polymers and their members receive a discount on the article processing charges.

Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
High Visibility: indexed within Scopus, SCIE (Web of Science), Ei Compendex, PubMed, PMC, FSTA, CAPlus / SciFinder, Inspec, and other databases.
Journal Rank: JCR - Q1 (Polymer Science) / CiteScore - Q1 (General Chemistry & Polymers and Plastics)
Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.5 days after submission; acceptance to publication is undertaken in 2.6 days (median values for papers published in this journal in the second half of 2024).
Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in MDPI journals, in appreciation of the work.
Testimonials: See what our authors and editors say about Polymers.

Impact Factor: 4.7 (2023); 5-Year Impact Factor: 4.9 (2023)

Imprint Information Journal Flyer Open Access ISSN: 2073-4360

Latest Articles

24 pages, 4111 KiB

Open AccessArticle

Interactions and Curing Dynamics Between UV-Triggered Epoxy Acrylate Binder, Curing Agents and Photoinitiators

by Ji-min Choi, Sang Jang and Keon-Soo Jang

Polymers 2025, 17(9), 1252; https://doi.org/10.3390/polym17091252 (registering DOI) - 4 May 2025

This study investigated the interaction between UV-triggered curing binders and photoinitiators, focusing on their thermal, mechanical, and morphological properties. Using epoxy acrylate as the matrix and three potential photoinitiators with varying phosphorus contents, UV curing systems were fabricated and analyzed. 2-hydroxy-2-methyl-1-phenyl-1-propanone (HMPP), 2,4,6-trimethyl [...] Read more.

This study investigated the interaction between UV-triggered curing binders and photoinitiators, focusing on their thermal, mechanical, and morphological properties. Using epoxy acrylate as the matrix and three potential photoinitiators with varying phosphorus contents, UV curing systems were fabricated and analyzed. 2-hydroxy-2-methyl-1-phenyl-1-propanone (HMPP), 2,4,6-trimethyl benzoyl diphenyl phosphine oxide (TPO), and their mixture were utilized as photoinitiators. We observed that the curing process significantly reduced residual double bonds within the first 5 s of UV irradiation time. The glass transition temperature (T_g) increased with curing time due to enhanced network density. For instance, in the MyA–TPO formulation, T_g of the cured sample tended to increase to 67.3 °C for 3 s to 79.8 °C for 15 s. Mechanical analysis revealed that HMPP facilitated the formation of robust network structures. Notably, the MyA–HMPP formulation exhibited a tensile strength of 63 MPa and a Young’s modulus of 21 MPa, indicating excellent mechanical strength. SEM imaging confirmed these findings, illustrating distinct fracture morphologies that correlated with mechanical performance. These results provide insights into optimizing UV-curable materials for applications requiring high precision and durability. In particular, the combination of high T_g, superior tensile strength, and uniform fracture morphology indicates excellent thermal stability, mechanical integrity, and crack resistance—critical requirements in semiconductor packaging. These properties, along with rapid UV curing, support the suitability of the proposed systems for advanced applications such as system-in-package (SiP) and 3D integration. Full article

(This article belongs to the Special Issue Advanced Epoxy-Based Materials, 5th Edition)

► Show Figures

Figure 1

13 pages, 3837 KiB

Open AccessArticle

Automotive Application of Chemically Foamed rPET

by Veronika Anna Szabó, András Kovács, Sándor Kálmán Jakab, Tamara Zsuzsanna Böcz and Gábor Dogossy

Polymers 2025, 17(9), 1251; https://doi.org/10.3390/polym17091251 (registering DOI) - 4 May 2025

This study investigated the automotive applicability of parts produced from a newly developed foamed recycled polyethylene terephthalate (rPET). The injection molded part contained a combination of both endothermic and exothermic foaming agents and phosphorus (Exolit OP 1240) (OP)- and melamine polyphosphate (MPP)-based flame [...] Read more.

This study investigated the automotive applicability of parts produced from a newly developed foamed recycled polyethylene terephthalate (rPET). The injection molded part contained a combination of both endothermic and exothermic foaming agents and phosphorus (Exolit OP 1240) (OP)- and melamine polyphosphate (MPP)-based flame retardant agents. The parts were produced using a breathing mold technique to achieve a suitable level of foaming. The aim was to produce lighter parts made of recycled material that also complied with the fire safety automotive industry standards. Computer tomographic scans revealed the foam structure formed successfully, which contributed to an improved strength-to-weight ratio. The scans further showcased that larger cells tended to form in the thicker areas within the part, while smaller cells generally formed in the thinner areas. Finite element simulations showed that the large cell formation in the thicker parts had no effect on the part’s load bearing property, and there were not stress concentration points after the boundary conditions were defined. The sample produced from the material was determined to be a possible replacement of small-sized automotive components. Full article

(This article belongs to the Section Polymer Fibers)

► Show Figures

Figure 1

24 pages, 5754 KiB

Open AccessArticle

Mechanical and Ultrasonic Evaluation of Epoxy-Based Polymer Mortar Reinforced with Discrete Fibers

by Eyad Alsuhaibani

Polymers 2025, 17(9), 1250; https://doi.org/10.3390/polym17091250 (registering DOI) - 4 May 2025

This research investigates the ultrasonic pulse velocity (UPV) and mechanical performance of epoxy-based polymer mortar (PM) reinforced with discrete fiber types to enhance structural behavior and promote sustainable construction practices. Four fiber types, polypropylene (PPF), natural date palm leaf fiber (DPL), glass fiber [...] Read more.

This research investigates the ultrasonic pulse velocity (UPV) and mechanical performance of epoxy-based polymer mortar (PM) reinforced with discrete fiber types to enhance structural behavior and promote sustainable construction practices. Four fiber types, polypropylene (PPF), natural date palm leaf fiber (DPL), glass fiber (GF), and carbon fiber (CF), were incorporated at varying volume fractions (0.5%, 1.0%, and 1.5%) into PM matrices. A total of thirteen mixtures, including a fiber-free control, were prepared. UPV testing was conducted prior to mechanical testing to evaluate internal quality and homogeneity, followed by compressive and flexural strength tests to assess structural performance. The results demonstrated that fiber type and dosage significantly influenced fiber-reinforced PM (FRPM) behavior. UPV values showed strong positive correlations with compressive strength for PPF, DPL, and CF, confirming UPV’s role as a non-destructive quality indicator. GF at 0.5% yielded the highest compressive strength (54.4 MPa), while CF and GF at 1.5% provided the greatest flexural enhancements (15 MPa), indicating improved ductility and energy absorption. Quadratic regression models were developed to predict strength responses as functions of fiber dosage. Although statistical significance was not achieved due to limited sample size, models for PPF and CF exhibited strong predictive reliability. Natural fibers such as DPL demonstrated moderate performance while offering environmental advantages through local renewability and low embodied energy. The study concludes that low fiber dosages, particularly 0.5%, enhance mechanical performance and material efficiency in FRPMs. The findings underscore the potential of FRPM as a durable and sustainable alternative to traditional cementitious materials. Full article

(This article belongs to the Section Polymer Fibers)

► Show Figures

Figure 1

28 pages, 4098 KiB

Open AccessReview

Advances in the Study of Flame-Retardant Cellulose and Its Application in Polymers: A Review

by Quan Yuan, Shaodong Wang, Liping He and Shiwei Xu

Polymers 2025, 17(9), 1249; https://doi.org/10.3390/polym17091249 (registering DOI) - 3 May 2025

Cellulose, as a green and renewable polymer material, has attracted the attention of a wide range of scholars for its excellent mechanical strength, easy chemical modification and degradability. However, its flammability limits its application in automotive, aerospace, construction, textile and electronic fields. This [...] Read more.

Cellulose, as a green and renewable polymer material, has attracted the attention of a wide range of scholars for its excellent mechanical strength, easy chemical modification and degradability. However, its flammability limits its application in automotive, aerospace, construction, textile and electronic fields. This review recapitulates the modification methods of flame-retardant cellulose and their applications in polymers in recent years. This paper discusses the fabrication of flame-retardant cellulose from various aspects such as boron, nitrogen, phosphorus, sulphur, inorganic and heterogeneous synergistic modification, respectively, and evaluates the flame retardancy of flame-retardant cellulose by means of thermogravimetry, cone calorimetry, limiting oxygen index, the vertical combustion of UL94, etc. Finally, it discusses the application of flame-retardant cellulose in actual composites, which fully reflects the extraordinary potential of flame-retardant cellulose for applications in polymers. Currently, flame-retardant cellulose has significantly improved its flame-retardant properties through multi-faceted modification strategies and has shown a broad application prospect in composite materials. However, interfacial compatibility, environmental protection and process optimisation are still the key directions for future research, and efficient, low-toxic and industrialised flame-retardant cellulose materials need to be realised through innovative design. Full article

(This article belongs to the Special Issue Recent Developments in Polymeric Composites and Hybrid Materials Through Advanced Manufacturing)

► Show Figures

Figure 1

37 pages, 15841 KiB

Open AccessArticle

Experimental, Simulation and Theoretical Insights into Anisotropic Thermal Behavior of Epoxy Nanocomposites Reinforced with Carbonaceous Nanofillers

by Giovanni Spinelli, Rosella Guarini, Liberata Guadagno, Carlo Naddeo, Luigi Vertuccio and Vittorio Romano

Polymers 2025, 17(9), 1248; https://doi.org/10.3390/polym17091248 (registering DOI) - 3 May 2025

Understanding and optimizing thermal conductivity in epoxy-based composites is crucial for efficient thermal management applications. This study investigates the anisotropic thermal conductivity of a tetra-functional epoxy resin filled with low concentrations (0.25–2.00 wt%) of carbonaceous nanofillers: 1D multiwall carbon nanotubes (MWCNTs) and 2D [...] Read more.

Understanding and optimizing thermal conductivity in epoxy-based composites is crucial for efficient thermal management applications. This study investigates the anisotropic thermal conductivity of a tetra-functional epoxy resin filled with low concentrations (0.25–2.00 wt%) of carbonaceous nanofillers: 1D multiwall carbon nanotubes (MWCNTs) and 2D exfoliated graphite (EG) nanoparticles. Experimental measurements conducted using the Transient Plane Source (TPS) method reveal distinct behaviors depending on the nanofiller’s geometry. Epoxy formulations incorporating MWCNTs exhibit a ~60% increase in in-plane thermal conductivity (λ_{I-p dir.}) compared to the unfilled resin, with negligible changes in the through-plane direction (λ_{T-p dir.}). Conversely, EG nanoparticles enhance thermal conductivity in both directions, with a preference for the in-plane direction, achieving a ~250% increase at 2 wt%. In light of this, graphene-based fillers establish a predominant thermal transport direction in the resulting nanocomposites due to their layered structure, whereas MWCNTs create unidirectional thermal pathways. The TPS results were complemented by multiphysics simulations in COMSOL and theoretical studies based on the theory of thermal circuits to explain the observed phenomena and justify the experimental findings. This integrated approach, combining experiments, theoretical analyses, and simulations, demonstrates the potential for tailoring the thermal properties of epoxy nanocomposites. These insights provide a foundation for developing advanced materials optimized for efficient thermal management in high-performance systems. Full article

(This article belongs to the Special Issue Advances in Functional Polymers and Composites: 2nd Edition)

► Show Figures

Figure 1

20 pages, 4879 KiB

Open AccessArticle

Design, Characterization, and Preparation of New Smart Photoactive Polymers and Their Capacity for Photodynamic Antimicrobial Action in Organic Film

by Oscar G. Marambio, Franco I. Barrera, Rudy Martin-Trasancos, Julio Sánchez, Christian Erick Palavecino and Guadalupe del C. Pizarro

Polymers 2025, 17(9), 1247; https://doi.org/10.3390/polym17091247 (registering DOI) - 3 May 2025

The photosensitive properties of smart photoactive polymers give them a wide range of potential applications across various fields. This study focuses on designing polymeric systems that incorporate hydrophilic polymers, with the primary goal of adapting these materials for biological applications. Specifically, it aims [...] Read more.

The photosensitive properties of smart photoactive polymers give them a wide range of potential applications across various fields. This study focuses on designing polymeric systems that incorporate hydrophilic polymers, with the primary goal of adapting these materials for biological applications. Specifically, it aims to contribute to the development of photochromic materials for optical processing, utilizing both molecular and macromolecular components. Additionally, this study evaluates the effectiveness of photoactive polymers in photodynamic therapy (PDT). It details the synthesis and characterization of photoactive copolymers derived from maleic anhydride (MAn) combined with vinyl monomers such as 2-methyl-2-butene (MB) and 1-octadecene (OD), as well as the organic compound 1-(2-hydroxyethyl)-3,3-dimethylindoline-6-nitrobenzopyran (SP). The two novel optically active alternating polymeric systems, poly(maleic anhydride-alt-octadecene) and poly(maleic anhydride-alt-2-methyl-2-butene), were functionalized with SP through an esterification process in a 1:1 monomer feed ratio, using pyridine as a catalyst. This methodology incorporated approximately 100% of the photoactive molecules into the main acrylic chain to prepare the alternating copolymers. These copolymers were characterized by UV-visible, FTIR, and 1H-NMR spectroscopy and analysis of their optical and thermal properties. When exposed to UV light, the photoactive polymer films can develop a deep blue color (566 nm in the absorption spectra). Finally, the study also assesses their capacity for photodynamic antimicrobial action in organic film. Notably, the photoactive P(MAn-alt-2MB)-PS significantly enhances the photodynamic antimicrobial activity of the photosensitizer Ru(bpy) against two bacterial strains of Staphylococcus aureus, reducing the minimum inhibitory concentration (MIC) from 2 µg/mL to 0.5 µg/mL. Therefore, 4 times less photosensitizer is required when mixed with the photoactive polymer to inhibit the growth of antibiotic-sensitive and -resistant bacteria. Full article

(This article belongs to the Special Issue Smart and Bio-Medical Polymers: 2nd Edition)

► Show Figures

Graphical abstract

15 pages, 2434 KiB

Open AccessArticle

Innovative Sericin-Based Film-Forming Gel for Wound Healing: Development and Performance Evaluation

by Suprawee Wongtechanon, Chayanee Noosak, Pavarish Jantorn, Papitchaya Watcharanurak, Piyawut Swangphon, Warapond Wanna and Dennapa Saeloh Sotthibandhu

Polymers 2025, 17(9), 1246; https://doi.org/10.3390/polym17091246 (registering DOI) - 3 May 2025

The development of effective wound dressings remains a critical challenge in medical treatments, requiring materials that promote healing, minimize infection, and enhance tissue regeneration. This study evaluated the wound-healing potential of sericin-based film-forming gels. Six formulations were developed by combining varying concentrations of [...] Read more.

The development of effective wound dressings remains a critical challenge in medical treatments, requiring materials that promote healing, minimize infection, and enhance tissue regeneration. This study evaluated the wound-healing potential of sericin-based film-forming gels. Six formulations were developed by combining varying concentrations of sericin, a protein derived from silk cocoons, with polyvinyl alcohol (PVA). These formulations were evaluated for physical properties including drying time, pH, spreadability, stability, swelling ratio, flexibility, and adhesion. Film-forming gel is an attractive option for wound dressing due to its flexibility, adhesion, and infrequent reapplication. The F4 formulation (1% sericin) demonstrated superior performances in drying time, spreadability, stability, swelling ratio, flexibility, and skin adhesion, was easy to apply, and formed a stable film on drying. Biological evaluations showed that F4 exhibited excellent compatibility with skin fibroblast cells, maintained a suitable pH, and significantly promoted cell proliferation and migration. The F4 formulation also demonstrated anti-inflammatory effects by inhibiting iNOS expression and nitric oxide production, offering mechanical stability, biological activity, and ease of use with significant potential for treating acute and chronic wounds. Full article

(This article belongs to the Special Issue Advanced Biodegradable Polymers for Biomedical Applications)

► Show Figures

Graphical abstract

28 pages, 17005 KiB

Open AccessArticle

Impact and Failure Analysis of U-Shaped Concrete Containing Polyurethane Materials: Deep Learning and Digital Imaging Correlation-Based Approach

by Saleh Ahmad Laqsum, Han Zhu, Sadi I. Haruna, Yasser E. Ibrahim, Mohammed Amer, Ali Al-Shawafi and Omar Shabbir Ahmed

Polymers 2025, 17(9), 1245; https://doi.org/10.3390/polym17091245 - 2 May 2025

This study investigates the use of advanced convolutional neural networks (CNNs) to analyze and classify the fracture behavior of U-shaped concrete modified with polyurethane (PU) under repeated drop-weight impact loads. A total of 17 U-shaped specimens were tested under multiple drop-weight impact loads [...] Read more.

This study investigates the use of advanced convolutional neural networks (CNNs) to analyze and classify the fracture behavior of U-shaped concrete modified with polyurethane (PU) under repeated drop-weight impact loads. A total of 17 U-shaped specimens were tested under multiple drop-weight impact loads for each PU binder content (0%, 10%, 20%, and 30%) by weight of cement. By integrating digital image correlation (DIC) with dynamic and static mechanical testing, this research evaluates the concrete’s impact resistance and flexural behavior with varying PU binder content. Three CNN architectures, InceptionV3, MobileNet, and DenseNet121, were trained on a dataset comprising 1655 high-resolution crack images to classify the failure stages into no crack, initial crack, and advanced failure. Experimental results revealed that 20% PU content optimally enhances impact resistance and flexural strength, while mechanical properties declined significantly with 30% PU content. The strain localization in DIC analysis indicated reduced matrix cohesion, which was measured by the extent of strain concentration in the material, highlighting the importance of maintaining PU content below 20% to avoid compromising structural integrity. Among the models, InceptionV3 demonstrated superior accuracy (96.67%), precision, and recall, outperforming MobileNet (94.56%) and DenseNet121 (90.03%). The combination of DIC and deep learning offers a robust, automated framework for crack assessment, significantly improving accuracy and efficiency over traditional methods such as visual inspections, which are time-consuming and reliant on expert judgment. Full article

(This article belongs to the Special Issue Advances in the Preparation, Properties and Application of Polyurethane, Cellulose and Their Composites (3rd Edition))

► Show Figures

Figure 1

23 pages, 2570 KiB

Open AccessArticle

Thermal Degradation of Palm Fronds/Polypropylene Bio-Composites: Thermo-Kinetics and Convolutional-Deep Nueral Networks Techniques

by Abdulrazak Jinadu Otaru and Zaid Abdulhamid Alhulaybi Albin Zaid

Polymers 2025, 17(9), 1244; https://doi.org/10.3390/polym17091244 - 2 May 2025

Identifying sustainable and efficient methods for the degradation of plastic waste in landfills is critical for the implementation of the Saudi Green Initiative, the European Union’s Strategic Plan, and the 2030 United Nations Action Plan, all of which are aimed at achieving a [...] Read more.

Identifying sustainable and efficient methods for the degradation of plastic waste in landfills is critical for the implementation of the Saudi Green Initiative, the European Union’s Strategic Plan, and the 2030 United Nations Action Plan, all of which are aimed at achieving a sustainable environment. This study assesses the influence of palm fronds (PFR) on the thermal degradation of polypropylene plastic (PP) using TGA/FTIR experimental measurements, thermo-kinetics, and machine learning convolutional deep learning neural networks (CDNN). Thermal degradation operations were conducted on pure materials (PFR and PP) as well as mixed (blended) materials containing 25% and 50% PFR, across degradation temperatures ranging from 25 to 600 °C and heating rates of 10, 20, and 40 °C·min⁻¹. The TGA data indicated a synergistic interaction between the agricultural waste (PFR) and PP plastic, with decreased thermal stability at temperatures below 500 °C, attributed to the hemicellulose and cellulose present in the PFR biomass. In contrast, at temperatures exceeding 500 °C, the presence of lignin retards the degradation of the PFR biomass and blends. Activation energy values between 81.92 and 299.34 kJ·mol⁻¹ were obtained through the application of the Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) model-free methods. The application of CDNN facilitated the extraction of significant features and labels, which were crucial for enhancing modeling accuracy and convergence. This modeling and simulation approach reduced the overall cost function from 41.68 to 0.27, utilizing seven hidden neurons, and 673,910 epochs in 13.28 h. This method effectively bridged the gap between modeling and experimental data, achieving an R² value of approximately 0.992, and identified sample composition as the most critical parameter influencing the thermolysis process. It is hoped that such findings may facilitate an energy-efficient pathway necessary for the thermal decomposition of plastic materials in landfills. Full article

(This article belongs to the Special Issue Multiscale Modeling of Polymeric Systems for Time-Dependent Nonlinear Properties)

17 pages, 14504 KiB

Open AccessArticle

Construction of a Transparent, Robust, Shape-Memory and Self-Healing MDI-Based Polyurethane Elastomer

by Haichun Dang, Ziliang Zhang, Ruibing Sun, Yunlun Li, Mengyu Lin, Siting Yang, Maoyong He, Zhaozan Xu and Xiangcheng Bian

Polymers 2025, 17(9), 1243; https://doi.org/10.3390/polym17091243 - 2 May 2025

Integrating strong mechanical properties and excellent optical properties for self-healing materials is challenging in both academia and industry. Robust self-healing polyurethane elastomers are expected to have superior mechanical properties, transparency, remarkable healing capability, and shape-memory performance via the adjustment of chemical and microphase [...] Read more.

Integrating strong mechanical properties and excellent optical properties for self-healing materials is challenging in both academia and industry. Robust self-healing polyurethane elastomers are expected to have superior mechanical properties, transparency, remarkable healing capability, and shape-memory performance via the adjustment of chemical and microphase separation structure. Herein, a robust transparent self-healable 4,4′-diphenylmethane diisocyanate (MDI)-based polyurethane elastomer containing disulfide bonds and branched structure (MPUE-SS) was synthesized. The chemical and topological structures, compatibility of soft–hard phases, and hard domain size of polyurethane could be adjusted via branched structure and mixed chain extender containing disulfide bonds and 1,4-butanediol (BDO), leading to enhanced self-healing, transparency, and mechanical properties. MPUE-SS exhibited a maximal tensile strength of 40 MPa. The microphase separation structure and reduced crystallinity led to a high transparency of about 91%, close to that of alicyclic polyurethane elastomers. After cutting in half and splicing, the MPUE-SS film recovered more than 95% of the original mechanical properties in 24 h. The shape recovery ratio at 40 °C and shape fixity ratio at −20 °C of MPUE-SS were 96.0% and 99.6%, respectively, higher than those of MPUE without disulfide bonds. Therefore, the chemical, topological structures, and microphase separation of polyurethane could be adjusted to achieve desired self-healing, transparency, shape-memory, and mechanical properties. Full article

(This article belongs to the Special Issue Functional Polymers: Interaction, Surface, Processing and Applications: 3rd Edition)

► Show Figures

Figure 1

12 pages, 3536 KiB

Open AccessArticle

Rapid Assembly of Block Copolymer Thin Films via Accelerating the Swelling Process During Solvent Annealing

by Tian-en Shui, Tongxin Chang, Zhe Wang and Haiying Huang

Polymers 2025, 17(9), 1242; https://doi.org/10.3390/polym17091242 - 2 May 2025

Block copolymer (BCP) lithography is widely regarded as a promising next-generation nanolithography technique. However, achieving rapid assembly with defect-free morphology remains a significant challenge for its practical application. In this study, we presented a facile and efficient solvent annealing method for fabricating well-ordered [...] Read more.

Block copolymer (BCP) lithography is widely regarded as a promising next-generation nanolithography technique. However, achieving rapid assembly with defect-free morphology remains a significant challenge for its practical application. In this study, we presented a facile and efficient solvent annealing method for fabricating well-ordered BCP thin films within minutes on both flat and topographically patterned substrates. By accelerating the swelling process, rapid film swelling was observed within just 10 s of annealing, leading to well-ordered morphologies in 1~3 min. Furthermore, we systematically investigated the influence of swelling ratio (SR) on film morphology by precisely tuning solvent vapor pressure. For cylinder-forming poly(styrene-block-2-vinylpyridine) (PS-b-P2VP) films, we identified three distinct SR-dependent ordering regimes: (I) Excessive SR led to a disordered morphology; (II) near-optimal SR balanced long-range and short-range orders, and a slight increase in SR enhanced the long-range order but introduced short-range defects. (III) Insufficient SR failed to provide adequate chain mobility, limiting long-range order development. These findings highlight the critical role of SR in controlling defect density in nanopatterned surfaces. Long-range-ordered BCP nanopatterns can only be achieved under optimal SR conditions that ensure sufficient chain mobility. We believe this rapid annealing strategy, which is also applicable to other solvent-based annealing systems for BCP films, may contribute to next-generation nanolithography for microfabrication. Full article

(This article belongs to the Special Issue Advances in Block Copolymers: Synthesis, Characterization and Applications)

► Show Figures

Figure 1

21 pages, 8241 KiB

Open AccessArticle

Chemical Recycling of Bio-Based Thermosetting Epoxy Composite Produced by Vacuum-Assisted Resin Infusion Process

by Liberata Guadagno, Raffaele Longo, Marialuigia Raimondo, Luigi Vertuccio, Francesca Aliberti, Lorenzo Bonadies, Simone Morciano, Luigia Longo, Roberto Pantani and Elisa Calabrese

Polymers 2025, 17(9), 1241; https://doi.org/10.3390/polym17091241 - 2 May 2025

This research work focuses on the chemical recycling of a Carbon Fiber-Reinforced Composite (CFRC) manufactured through a vacuum-assisted resin infusion (VARI) process, characterized by a high Young’s modulus of approximately 7640 MPa. The recycling reaction was performed using a mixture of eco-sustainable solvents, [...] Read more.

This research work focuses on the chemical recycling of a Carbon Fiber-Reinforced Composite (CFRC) manufactured through a vacuum-assisted resin infusion (VARI) process, characterized by a high Young’s modulus of approximately 7640 MPa. The recycling reaction was performed using a mixture of eco-sustainable solvents, composed of acetic acid and hydrogen peroxide, and was conducted at three different temperatures (70, 80, and 90 °C). The reaction yield values, evaluated with an innovative approach that involved the use of thermogravimetric analysis (TGA), confirmed the importance to recycle at a temperature corresponding to the glass transition temperature (Tg = 90.3 °C) of the resin. Spectroscopic investigations highlighted that the chemical bond cleavage occurred through the selective breaking of the C-N bonds of the cross-linked matrix structure, allowing the recovery of both the reinforcing phase of the epoxy matrix and the initial oligomers/monomers of the epoxy matrix. The morphological and electrical investigations carried out on the recovered fibers further confirmed the efficiency of the recycling process conducted at the highest explored temperature, allowing the recovery of cleaner fibers with an electrical conductivity value (8.04 × 10² S/m) closer to that of virgin fibers (2.20 × 10³ S/m). The proposed strategy is a true challenge in terms of saving energy, solving waste disposal problems, preserving the earth, and preventing the depletion of planet resources. Full article

(This article belongs to the Section Circular and Green Sustainable Polymer Science)

► Show Figures

Figure 1

19 pages, 3566 KiB

Open AccessArticle

Isolation and Characterization of Cellulose Nanocrystals from Bacterial Cellulose Synthesized via Ancylobacter sp. STN1A Using Residual Glycerol

by Manuel Peña-Ortiz, Araceli García, Sophie Marie Martirani-Von Abercron, Patricia Marín, Silvia Marqués, Ramzi Khiari, Alain Dufresne and Luis Serrano

Polymers 2025, 17(9), 1240; https://doi.org/10.3390/polym17091240 - 1 May 2025

Given the growing interest in the functional properties of nanocellulosic forms, bacterial cellulose nanocrystals (BCNCs) have gained attention as sustainable, high-performance materials for diverse applications. Although recent research has addressed the use of agro-industrial waste for BCNCs production, limited attention has been given [...] Read more.

Given the growing interest in the functional properties of nanocellulosic forms, bacterial cellulose nanocrystals (BCNCs) have gained attention as sustainable, high-performance materials for diverse applications. Although recent research has addressed the use of agro-industrial waste for BCNCs production, limited attention has been given to residual crude glycerol, a widespread byproduct of the biodiesel industry. Therefore, this work aimed to synthesize and thoroughly characterize BCNCs from bacterial nanocellulose (BNC) obtained through the metabolism of crude glycerol via the novel bacterial strain Ancylobacter sp. STN1A. The influence of sulfuric acid (H₂SO₄) hydrolysis time on BCNCs´ morphology and physicochemical properties was evaluated. Severe hydrolysis conditions yielded shorter, narrower nanocrystals (0.91 μm × 40 nm; L/D = 22.8) with increased crystallinity (63%) and high colloidal stability (−40.17 ± 0.68 mV), as well as slightly reduced thermal stability. In contrast, milder conditions produced longer BCNCs (1.13 μm × 42 nm; L/D = 26.9) with similarly high zeta potential (−44.13 ± 0.73 mV), while maintaining the thermal and crystalline features of the starting BNC. These findings demonstrate the potential to tailor BCNCs´ properties through controlled hydrolysis and support the viability of producing versatile nanocellulosic materials from residual byproducts, contributing to both cost-effective production and environmental sustainability. Full article

(This article belongs to the Special Issue Advanced Cellulose Polymers and Derivatives)

► Show Figures

Figure 1

20 pages, 10692 KiB

Open AccessArticle

Optimization of Adhesion in Textile Cord–Rubber Composites: An Experimental and Predictive Modeling Approach

by Merve Pehlivan, Bora Atalik, Sezgin Gokcesular, Sunullah Ozbek and Belma Ozbek

Polymers 2025, 17(9), 1239; https://doi.org/10.3390/polym17091239 - 1 May 2025

The adhesion between rubber compounds and textile cords plays a critical role in determining the overall performance and durability of rubber-based composites, particularly in tire applications. Despite extensive research on adhesion mechanisms, optimizing adhesion through systematic modeling remains challenging due to the complex [...] Read more.

The adhesion between rubber compounds and textile cords plays a critical role in determining the overall performance and durability of rubber-based composites, particularly in tire applications. Despite extensive research on adhesion mechanisms, optimizing adhesion through systematic modeling remains challenging due to the complex interactions between rubber formulations, textile treatment, and processing conditions. This study presents an integrated experimental and predictive modeling approach to investigate and optimize the adhesion performance of nylon 6.6 textile cords in rubber compounds. Initially, the effects of different accelerator types—including diphenyl guanidine (DPG), 2,2′-Dithiobis(benzothiazole) (MBTS), N-tert-butyl-2-benzothiazole sulfenamide (TBBS), and N-cyclohexyl-2-benzothiazole sulfenamide (CBS)—on adhesion properties were systematically evaluated. Key parameters such as cure characteristics, Mooney viscosity, and mechanical properties of the rubber compounds were analyzed using a moving die rheometer (MDR), Mooney viscometer, and tensometer. To enhance adhesion performance, a statistical optimization approach based on the Box–Behnken design was employed, focusing on the influence of accelerator, curing agent, and resin contents. The results indicate that an optimized rubber formulation comprising 1.6 phr curing agent, 0.3 phr resin (HMMM), and 0.5 phr accelerator (MBTS) yields the highest adhesion strength. This study provides the first systematic modeling of adhesion between nylon 6.6 textile cords and rubber compounds using response surface methodology (RSM), offering valuable insights into the material design for improved interfacial bonding in tire manufacturing. Full article

(This article belongs to the Special Issue Polymer-Based Adhesives: Preparation, Characterization and Applications)

► Show Figures

Figure 1

14 pages, 7525 KiB

Open AccessArticle

Novel Molecular Weight Gradient Hyaluronate Dissolving Microneedles for Sustained Intralesional Delivery and Photodynamic Activation of Hematoporphyrin in Port-Wine Stain Therapy

by Xueli Peng, Chenxin Yan, Nengquan Fan, Chaoguo Sun, Suohui Zhang and Yunhua Gao

Polymers 2025, 17(9), 1238; https://doi.org/10.3390/polym17091238 - 1 May 2025

Port-wine stain (PWS), a progressive congenital vascular malformation characterized by ectatic dermal capillaries, demonstrates age-dependent lesion expansion and chromatic intensification, resulting in significant psychosocial comorbidity. While systemic hematoporphyrin (HP) administration remains the clinical paradigm for photodynamic therapy (PDT), its therapeutic utility is severely [...] Read more.

Port-wine stain (PWS), a progressive congenital vascular malformation characterized by ectatic dermal capillaries, demonstrates age-dependent lesion expansion and chromatic intensification, resulting in significant psychosocial comorbidity. While systemic hematoporphyrin (HP) administration remains the clinical paradigm for photodynamic therapy (PDT), its therapeutic utility is severely constrained by non-targeted biodistribution. Pharmacokinetic analyses reveal prolonged dermal retention and suboptimal lesion accumulation, predisposing 42% of patients to phototoxic reactions. To address these limitations, this work creatively suggested a local targeted drug delivery method based on soluble microneedles in response to the difficulties mentioned above. The rational design of a molecular weight (MW) HA gradient system enabled the engineering of ternary nanocomposite microneedles with enhanced biomechanical integrity (0.49 N/needle) and superior HP loading capacity, which collectively facilitated spatiotemporally controlled transdermal delivery of hematoporphyrin with complete dissolution within 30 min. The release performance, skin permeability, and storage stability of hematoporphyrin dissolving microneedles (HP-DMNs) have all been demonstrated in vitro. This study applies soluble microneedle technology to the delivery of HP in PWS for the first time. It avoids the risk of systemic exposure through precise local administration. It uses the rapid dissolution properties of microneedles to achieve high concentration and rapid release of drugs in skin lesions. This study provides a new strategy for sustained intralesional release and rapid drug delivery treatment of PWS and provides novel ideas for the development of new formulations of HP and related photosensitizers. Full article

(This article belongs to the Special Issue Polymers and Their Role in Drug Delivery, 2nd Edition)

► Show Figures

Figure 1

34 pages, 7574 KiB

Open AccessReview

Recent Advances in Polyphenylene Sulfide-Based Separators for Lithium-Ion Batteries

by Lianlu Wan, Haitao Zhou, Haiyun Zhou, Jie Gu, Chen Wang, Quan Liao, Hongquan Gao, Jianchun Wu and Xiangdong Huo

Polymers 2025, 17(9), 1237; https://doi.org/10.3390/polym17091237 - 30 Apr 2025

Polyphenylene sulfide (PPS)-based separators have garnered significant attention as high-performance components for next-generation lithium-ion batteries (LIBs), driven by their exceptional thermal stability (>260 °C), chemical inertness, and mechanical durability. This review comprehensively examines advances in PPS separator design, focusing on two structurally distinct [...] Read more.

Polyphenylene sulfide (PPS)-based separators have garnered significant attention as high-performance components for next-generation lithium-ion batteries (LIBs), driven by their exceptional thermal stability (>260 °C), chemical inertness, and mechanical durability. This review comprehensively examines advances in PPS separator design, focusing on two structurally distinct categories: porous separators engineered via wet-chemical methods (e.g., melt-blown spinning, electrospinning, thermally induced phase separation) and nonporous solid-state separators fabricated through solvent-free dry-film processes. Porous variants, typified by submicron pore architectures (<1 μm), enable electrolyte-mediated ion transport with ionic conductivities up to >1 mS·cm⁻¹ at >55% porosity, while their nonporous counterparts leverage crystalline sulfur-atom alignment and trace electrolyte infiltration to establish solid–liquid biphasic conduction pathways, achieving ion transference numbers > 0.8 and homogenized lithium flux. Dry-processed solid-state PPS separators demonstrate unparalleled thermal dimensional stability (<2% shrinkage at 280 °C) and mitigate dendrite propagation through uniform electric field distribution, as evidenced by COMSOL simulations showing stable Li deposition under Cu particle contamination. Despite these advancements, challenges persist in reconciling thickness constraints (<25 μm) with mechanical robustness, scaling solvent-free manufacturing, and reducing costs. Innovations in ultra-thin formats (<20 μm) with self-healing polymer networks, coupled with compatibility extensions to sodium/zinc-ion systems, are identified as critical pathways for advancing PPS separators. By addressing these challenges, PPS-based architectures hold transformative potential for enabling high-energy-density (>500 Wh·kg⁻¹), intrinsically safe energy storage systems, particularly in applications demanding extreme operational reliability such as electric vehicles and grid-scale storage. Full article

(This article belongs to the Section Polymer Applications)

23 pages, 1381 KiB

Open AccessArticle

Size and Shape of Primary (Bio)Polyelectrolyte Complexes Chitosan/Gelatin: Study Using Small-Angle X-Ray Scattering from Synchrotron Radiation

by Podshivalov Aleksandr, Litvinov Mikhail, Kashurin Aleksandr and Danilova Ksenia

Polymers 2025, 17(9), 1236; https://doi.org/10.3390/polym17091236 - 30 Apr 2025

In this work, using small-angle X-ray scattering from synchrotron radiation, the macromolecular structure of chitosan and gelatin polyelectrolytes and their mixtures at various pH values and ratios was studied to determine the size and shape of primary supramolecular (bio)PEC. Analysis of the scattering [...] Read more.

In this work, using small-angle X-ray scattering from synchrotron radiation, the macromolecular structure of chitosan and gelatin polyelectrolytes and their mixtures at various pH values and ratios was studied to determine the size and shape of primary supramolecular (bio)PEC. Analysis of the scattering profiles of the initial solutions of chitosan and gelatin with the building of the pair distance function showed the formation of single-modal distributions with a maximum molecular size of 46 and 32.2 nm, respectively. Ab initio reconstruction of the macromolecule’s shape showed the formation of objects shaped like an oblate spheroid. In mixtures of chitosan and gelatin at a pH below the isoelectric point, it was found that the scattering structures correspond to the initial biopolymers. However, it is observed that values of the aspect ratio at a ratio above 1:10 gradually increase, which indicates a slight elongation of the average particle and indirectly indicates the formation of dissipative structures of (bio)PEC. In mixtures at a pH above the isoelectric point, it was shown that at ratios above 1:5, the formation of primary supramolecular complexes is observed, which is accompanied by an increase in zero-scattering intensity by about three times, maximum molecular size by two to two-and-a-half times relative to the initial polymers, and the formation of elongated structures corresponding to the cylinder (swollen spiral). It may be a consequence of the increased efficiency of the polyelectrolyte associative interaction between chitosan and gelatin. Full article

(This article belongs to the Special Issue Advances in Polyelectrolytes and Polyelectrolyte Complexes)

16 pages, 7475 KiB

Open AccessArticle

Environmental and Economic Impacts of Substituting Single-Use Plastic Straws: A Life-Cycle Assessment for Greece

by Panagiota Eleni and Christos Boukouvalas

Polymers 2025, 17(9), 1235; https://doi.org/10.3390/polym17091235 - 30 Apr 2025

The usage of more than 30 billion straws a year has been reported in the European Union (EU), in 2020, one year before the official ban of single-use plastics in Europe. The impacts of this plastic waste on the environment and on our [...] Read more.

The usage of more than 30 billion straws a year has been reported in the European Union (EU), in 2020, one year before the official ban of single-use plastics in Europe. The impacts of this plastic waste on the environment and on our health are global and can be drastic. Since then, various alternative straws have emerged. This study assesses their effectiveness, primarily from an environmental perspective, to determine the best option among those available. Life-cycle assessment (LCA) was conducted using ReCiPe 2016 methodology and ISO 14040/44 standards, alongside a preliminary cost analysis and a consumer preference survey. The findings reveal that wheat straws demonstrated the lowest overall environmental impact, with a climate change contribution of only 0.0568 kg CO₂ eq. per year, while plastic straws showed the lowest cost at EUR 0.30 per year but contributed 0.084 kg CO₂ eq. Metallic straws, despite being reusable, had the highest washing-related emissions, with 85% of their annual impact (~0.169 kg CO₂ eq.) attributed to dishwashing. Paper and bioplastic alternatives showed up to 2.5 times higher climate impacts than plastic. Cost-wise, bamboo straws reached EUR 7.97/year, while silicone and metal straws were more economically favorable at EUR 1.17 and EUR 2.81, respectively. The consumer survey highlighted that 85% of users preferred traditional plastic straws, but 76% were open to reusable alternatives. From a socio-economic point of view, cost seems to play a minor role. However, consumers’ preferences towards the new products and their awareness of health and environmental risks are very significant factors affecting their approval of new alternatives and their displeasure towards traditional straw elimination. Full article

(This article belongs to the Special Issue From Biomass Fractionation to Final Biobased Polymer Nanocomposites in European Sustainable Biobased Nanomaterials Community (BIOMAC))

► Show Figures

Figure 1

17 pages, 1820 KiB

Open AccessArticle

Biomimetic Grooved Ribbon Aerogel Inspired by the Structure of Pinus sylvestris var. mongolica Needles for Efficient Air Purification

by Bo Zhao, Zikun Huang, Mingze Han, Bernardo Predicala, Qiushi Wang, Yunhong Liang, Mo Li, Xin Liu, Jiangtao Qi and Li Guo

Polymers 2025, 17(9), 1234; https://doi.org/10.3390/polym17091234 - 30 Apr 2025

Air pollutants, such as particulate matter (PM) and ammonia (NH₃), generated by intensive animal farming pose considerable threats to human health, animal welfare, and ecological balance. Conventional materials are often ineffective at simultaneously removing multiple pollutants, maintaining a low pressure drop, [...] Read more.

Air pollutants, such as particulate matter (PM) and ammonia (NH₃), generated by intensive animal farming pose considerable threats to human health, animal welfare, and ecological balance. Conventional materials are often ineffective at simultaneously removing multiple pollutants, maintaining a low pressure drop, and ensuring durability in heavily polluted environments. Inspired by the dust-retention properties of Pinus sylvestris var. mongolica (PS) needles, this study developed a biomimetic grooved ribbon fiber using electrospinning technology. These fibers were further assembled into a three-dimensional bioinspired aerogel structure through freeze-forming technology to achieve efficient dust capture. Additionally, the introduction of UiO-66-NH₂ nanoparticles significantly enhanced the properties of the aerogels for NH₃ adsorption. Among the various prepared aerogels (PG, UPG-5, UPG-10, UPG-15, and UPG-20), UPG-10 demonstrated the best performance, achieving a filtration efficiency of 99.24% with a pressure drop of 95 Pa. Notably, it exhibited a remarkable dust-holding capacity of 147 g/m², and its NH₃ adsorption capacity reached 99.89 cm³/g, surpassing PG aerogel by 31.46 cm³/g. Additionally, UPG-10 exhibited outstanding elasticity, maintaining over 80% of its original shape after 30 compression cycles. This biomimetic aerogel presents a promising solution for air purification, contributing to improved agricultural efficiency and environmental sustainability. Full article

(This article belongs to the Special Issue Electrospun Polymer Nanofibers: Preparation, Design, and Characterization)

27 pages, 6454 KiB

Open AccessArticle

Low-Temperature Sealing Material Database and Optimization Prediction Based on AI and Machine Learning

by Honghao Jia, Zhongxu Tai, Rui Lyu, Kousuke Ishikawa, Yixiao Sun, Jianting Cao and Dongying Ju

Polymers 2025, 17(9), 1233; https://doi.org/10.3390/polym17091233 - 30 Apr 2025

Optimization of low-temperature sealing materials is of great significance to improving low-temperature performance and durability. This study leverages DeepSeek-v3 (DS) and GPT-generated data and applies machine learning methods, including XGBoost and neural networks, to perform 3D prediction and analysis of key properties of [...] Read more.

Optimization of low-temperature sealing materials is of great significance to improving low-temperature performance and durability. This study leverages DeepSeek-v3 (DS) and GPT-generated data and applies machine learning methods, including XGBoost and neural networks, to perform 3D prediction and analysis of key properties of low temperature sealing materials. Data expansion techniques were employed to enhance data quality and improve model prediction accuracy. Additionally, the study evaluates the applicability of AI-generated data in material performance prediction. The results demonstrate the effectiveness of machine learning in material optimization and provide valuable insights for future optimization strategies. Full article

(This article belongs to the Section Artificial Intelligence in Polymer Science)

More Articles...

Submit to Polymers Review for Polymers

Journal Menu

Journal Browser

► Journal Browser

Highly Accessed Articles

View More...

Latest Books

More Books and Reprints...

E-Mail Alert

News

30 April 2025
Richard DiMarchi and Rolf Müller Share the 2024 Tu Youyou Award

30 April 2025
MDPI INSIGHTS: The CEO's Letter #22 - 300 Journals in WoS, Norway & Sweden Consortiums, Self-citations

30 April 2025
Announcing the Award Committee for the 2024 Tu Youyou Award

More News & Announcements...

Topics

Propose a Topic

Topic in Chemistry, Materials, Molecules, Polymers, Pharmaceutics

Advanced Biomaterials: Processing and Applications Topic Editors: Vincenzo Guarino, Roberto De Santis, Ugo D'Amora
Deadline: 31 May 2025

Topic in Biomolecules, Energies, Foods, IJMS, Polymers

Microbes and Their Products for Sustainable Human Life Topic Editors: Shashi Kant Bhatia, Ranjit Gurav
Deadline: 7 July 2025

Topic in Fibers, J. Compos. Sci., Materials, Polymers

Advanced Carbon Fiber Reinforced Composite Materials, Volume II Topic Editors: Michela Simoncini, Archimede Forcellese
Deadline: 31 July 2025

Topic in Analytica, Molecules, Nanomaterials, Polymers, Separations, Chemosensors, Magnetochemistry

Nanomaterials in Green Analytical Chemistry Topic Editors: George Zachariadis, Rosa Peñalver, Natalia Manousi
Deadline: 15 August 2025

More Topics

Conferences

Announce Your Conference

3–5 November 2025 The 4th International Online Conference on Materials

19–21 November 2025 The 3rd International Online Conference on Polymer Science

3–5 December 2025 1st International Online Conference on Gels 2025

More Conferences...

Special Issues

Propose a Special Issue

Special Issue in Polymers

Polymer-Based Dielectric Composite Materials for Energy Applications Guest Editors: Gang Jian, Zixiong Sun
Deadline: 5 May 2025

Special Issue in Polymers

Advances in Functional Polymer Materials for Biomedical Applications Guest Editors: Libo Nie, Li Tang
Deadline: 5 May 2025

Special Issue in Polymers

Simulation and Calculation of Polymer Composite Materials Guest Editors: Han Liu, Maja Kuzmanović, Zhenhua Wei
Deadline: 5 May 2025

Special Issue in Polymers

Additive Manufacturing of Polymer Based Materials Guest Editors: Dana Luca Motoc, Santiago Ferrándiz-Bou
Deadline: 10 May 2025

More Special Issues

Topical Collections

Topical Collection in Polymers

Polymeric and Biopolymeric Materials: Recovery, Recycling and Reuse Collection Editors: Sławomir Borysiak, Łukasz Klapiszewski, Teofil Jesionowski

Topical Collection in Polymers

Polymerization and Kinetic Studies Collection Editors: Shin-Ichi Yusa, Binyuan Liu

Topical Collection in Polymers

Polymeric Coatings Collection Editor: Ilker S. Bayer

Topical Collection in Polymers

State-of-the-Art Polymer Science and Technology in Singapore Collection Editors: Somen K. Bhudolia, Wei Min Huang, Sunil Chandrakant Joshi, Swee Leong Sing

More Topical Collections

Back to TopTop