Polymers

15 pages, 1871 KiB

Open AccessArticle

A Gelatin-Based Film with Acerola Pulp: Production, Characterization, and Application in the Stability of Meat Products

by Vitor Augusto dos Santos Garcia, Giovana de Menezes Rodrigues, Victória Munhoz Monteiro, Rosemary Aparecida de Carvalho, Camila da Silva, Cristiana Maria Pedroso Yoshida, Silvia Maria Martelli, José Ignacio Velasco and Farayde Matta Fakhouri

Polymers 2025, 17(13), 1882; https://doi.org/10.3390/polym17131882 (registering DOI) - 6 Jul 2025

Abstract

The objective of this work was to produce and characterize active gelatin–acerola packaging films based on gelatin incorporated with different concentrations of acerola pulp and applied to evaluate the stability of meat products in packaging. The active films were produced by casting using [...] Read more.

The objective of this work was to produce and characterize active gelatin–acerola packaging films based on gelatin incorporated with different concentrations of acerola pulp and applied to evaluate the stability of meat products in packaging. The active films were produced by casting using gelatin (5%), sorbitol (0,1%), and acerola pulp (60, 70, 80, and 90%). The characterization of the acerola pulp was carried out. Visual aspects, thickness, pH, water vapor permeability, and total phenolic compounds were characterized in the films. The commercial acerola pulp presented the characteristics within the identity and quality standards. A good film formation capacity was obtained in all formulations, presenting the color parameters tending to red coloration, characteristic of the acerola pulp. The total phenolic compounds content ranged from 2.88 ± 70.24 to 3.94 ± 96.05 mg GAE/100 g, with 90 g of acerola pulp per 100 g of filmogenic solution. This film formulation was selected to apply in a vacuum pack of beef and chicken samples, analyzing the weight loss, color parameters, pH, water holding capacity, shear strength after 9 days of refrigeration storage, and soil biodegradability. Additionally, beef and chicken (in nature) were stored under the same conditions without using the wrapping film. The beef and chicken samples showed greater water retention capacity and color maintenance over the storage period compared to the control (without film addition). This way, active gelatin–acerola films can be considered a sustainable packaging alternative to preserve meat products. Full article

(This article belongs to the Special Issue Synthesis, Characterization and Applications of Natural Polymers, 2nd Edition)

► Show Figures

Figure 1

24 pages, 3541 KiB

Open AccessReview

Towards Intelligent Wound Care: Hydrogel-Based Wearable Monitoring and Therapeutic Platforms

by Yan Niu, Ziyao Zhao, Lihong Yang, Dan Lv, Rui Sun, Ting Zhang, Yuhan Li, Qianqian Bao, Mingqing Zhang, Lanzhong Wang, Wei Yan, Fei Han and Biwei Yan

Polymers 2025, 17(13), 1881; https://doi.org/10.3390/polym17131881 (registering DOI) - 6 Jul 2025

Abstract

Chronic wounds present clinical challenges due to persistent inflammation, infection, and dysregulated tissue repair, often exacerbated by the passive nature of conventional wound dressings. Recent advancements in hydrogel-based wearable technologies have transformed these biomaterials into multifunctional platforms capable of integrating real-time monitoring and [...] Read more.

Chronic wounds present clinical challenges due to persistent inflammation, infection, and dysregulated tissue repair, often exacerbated by the passive nature of conventional wound dressings. Recent advancements in hydrogel-based wearable technologies have transformed these biomaterials into multifunctional platforms capable of integrating real-time monitoring and targeted therapy, ushering in a new era of intelligent wound care. In this review, we show innovative diagnostic and therapeutic strategies, including wound-monitoring devices and multifunctional healing-promoted platforms, highlighting integrated closed-loop systems that dynamically adapt treatments to wound microenvironments, thus merging diagnostics and therapeutics. Challenges in fabrication engineering and clinical application are discussed, alongside emerging trends like AI-driven analytics and 3D-bioprinted technology. By bridging fragmented research, this work underscores the potential of hydrogels to enable intelligent wound management. Full article

(This article belongs to the Special Issue New Progress in the Polymer-Based Biomaterials)

► Show Figures

Figure 1

19 pages, 3482 KiB

Open AccessArticle

Enhancing the Energy Absorption Performance of 3D-Printed CF/TPU Composite Materials by Introducing a “Rigid–Elastic” Structure Through Multi-Scale Synergies

by Xuanyu Zhou, He Ouyang, Yuan Zhang, Ziqiang Zhu, Zhen Wang, Zirui Cheng, Yubing Hu and Yanan Zhang

Polymers 2025, 17(13), 1880; https://doi.org/10.3390/polym17131880 (registering DOI) - 6 Jul 2025

Abstract

Thermoplastic polyurethane (TPU) combines elastomeric and thermoplastic properties but suffers from insufficient rigidity and strength for structural applications. Herein, we developed novel carbon fiber-reinforced TPU (CF/TPU) composites filaments and utilize melt extrusion for 3D printing to maintain elasticity, while achieving enhanced stiffness and [...] Read more.

Thermoplastic polyurethane (TPU) combines elastomeric and thermoplastic properties but suffers from insufficient rigidity and strength for structural applications. Herein, we developed novel carbon fiber-reinforced TPU (CF/TPU) composites filaments and utilize melt extrusion for 3D printing to maintain elasticity, while achieving enhanced stiffness and strength through multi scale-the control of fiber content and optimization of printing parameters, reaching a rigid–elastic balance. A systematic evaluation of CF content (0–25%) and printing parameters revealed optimal performance to be at 220–230 °C and 40 mm/s for ensuring proper flow to wet fibers without polymer degradation. Compared with TPU, 20% CF/TPU exhibited 63.65%, 105.51%, and 93.69% improvements in tensile, compressive, and impact strength, respectively, alongside 70.88% and 72.92% enhancements in compression and impact energy absorption. This work establishes a fundamental framework for developing rigid–elastic hybrid materials with tailored energy absorption capabilities through rational material design and optimized additive manufacturing processes. Full article

(This article belongs to the Special Issue Research on Additive Manufacturing of Polymer Composites)

► Show Figures

Figure 1

21 pages, 9463 KiB

Open AccessArticle

Exploring the Potential of Cellulose Nanocrystals Originated from Ramie (Boehmeria nivea L. Gaud) in Formation of Microspheres for Enhanced Solubility of Furosemide

by Anis Yohana Chaerunisaa, Yoga Windhu Wardhana, Mayang Kusuma Dewi, Margaretha Efa Putri and Fitriani Jati Rahmania

Polymers 2025, 17(13), 1879; https://doi.org/10.3390/polym17131879 (registering DOI) - 5 Jul 2025

Abstract

Cellulose nanocrystals possess unique properties such as high surface area and excellent biocompatibility. They can disrupt strong hydrogen bonds and other intermolecular forces that hinder the solubility of certain molecules thus enhancing the solubility of poorly soluble materials. The main challenge in formulating [...] Read more.

Cellulose nanocrystals possess unique properties such as high surface area and excellent biocompatibility. They can disrupt strong hydrogen bonds and other intermolecular forces that hinder the solubility of certain molecules thus enhancing the solubility of poorly soluble materials. The main challenge in formulating poorly soluble drugs lies in their limited therapeutic efficacy due to inadequate solubility and bioavailability. Therefore, an innovative approach such as using cellulose nanocrystals to enhance the solubility is highly needed. The aim of this research is to study the potential of ramie (Boehmeria nivea L. Gaud) as a source of cellulose nanocrystals in the development of microspheres for the solubility enhancement of poorly soluble drugs. Nanocrystalline cellulose was isolated from the ramie (Boehmeria nivea L. Gaud) by optimizing hydrolysis conditions with varying acid concentrations and reaction times. Characterizations were performed by measuring particle size, pH, and sulfate content, followed by morphological study by SEM, functional group analysis, and thermal analysis. The use of sulfuric acid in the hydrolysis process of flax cellulose at 45 °C, as the type of acid that gives the best results, at 50% acid concentration for 60 min produces cellulose nanocrystallines with a particle size of 120 nm, sulfate concentration density of 133.09 mmol/kg, crystallinity of 96.2%, and a yield of 63.24 ± 8.72%. Furosemide was used as the poorly soluble drug model and its solubility enhancement in the form of furosemide/RNCC microspheres was evaluated through saturated solubility testing and in vitro dissolution. This study demonstrated that RNCC could improve the solubility of furosemide, which contributes to developing sustainable drug formulations and eco−friendly delivery systems for poorly soluble drugs. Full article

(This article belongs to the Section Polymer Applications)

11 pages, 4295 KiB

Open AccessArticle

Preliminary Study on the Development of a Biodegradable Functional Nasal Packing Material

by Dong Hoon Lee, EunA So, Faizan E Mustafa, Jae-ho Jeong and Bong-Kee Lee

Polymers 2025, 17(13), 1878; https://doi.org/10.3390/polym17131878 (registering DOI) - 5 Jul 2025

Abstract

Introduction: Functional endoscopic sinus surgery is commonly performed to treat paranasal sinus diseases, often necessitating nasal packing to control bleeding and aid healing. However, current materials can cause discomfort or lack adequate antibacterial properties. This study aimed to develop a biodegradable, biocompatible nasal [...] Read more.

Introduction: Functional endoscopic sinus surgery is commonly performed to treat paranasal sinus diseases, often necessitating nasal packing to control bleeding and aid healing. However, current materials can cause discomfort or lack adequate antibacterial properties. This study aimed to develop a biodegradable, biocompatible nasal packing material by combining polyvinyl alcohol (PVA) and carbon dots (CDs), and to evaluate its antibacterial activity and tissue compatibility. Materials and Methods: Electrospun nanofiber membranes were fabricated using PVA and biomass-derived CDs. Antibacterial efficacy of nasal packing variants (PVA, PVA-chitosan [CS], PVA-CS-CDs-1 mL, and PVA-CS-CDs-2 mL) was assessed using the Kirby–Bauer disk diffusion method against Escherichia coli, Salmonella spp., and Staphylococcus aureus. The in vivo biocompatibility was evaluated via histological analysis following implantation into the nasal cavity of mice. Results: All materials demonstrated antibacterial activity, with PVA-CS-CDs-2 mL showing the largest inhibition zones. Histological examination revealed minimal epithelial damage and no inflammation, with PVA-CS-CDs-2 mL yielding the most favorable tissue response. Conclusion: The PVA-CS-CDs composite demonstrates potential as a biocompatible, antibacterial nasal packing material. Further studies are warranted to validate its long-term clinical utility. Full article

(This article belongs to the Section Biobased and Biodegradable Polymers)

18 pages, 2880 KiB

Open AccessArticle

Novel Magnetically Charged Grafts for Vascular Repair: Process Optimization, Mechanical Characterization and In Vitro Validation

by Iriczalli Cruz-Maya, Roberto De Santis, Luciano Lanotte and Vincenzo Guarino

Polymers 2025, 17(13), 1877; https://doi.org/10.3390/polym17131877 (registering DOI) - 5 Jul 2025

Abstract

In the last decade, magnetic nanoparticles (MNPs) have attracted much attention for the implementation of non-invasive approaches suitable for the diagnosis and treatment of vascular diseases. In this work, the optimization of novel vascular grafts loaded with Nickel-based nanoparticles via electrospinning is proposed. [...] Read more.

In the last decade, magnetic nanoparticles (MNPs) have attracted much attention for the implementation of non-invasive approaches suitable for the diagnosis and treatment of vascular diseases. In this work, the optimization of novel vascular grafts loaded with Nickel-based nanoparticles via electrospinning is proposed. Two different polycarbonate urethanes—i.e., Corethane A80 (COT) and Chronoflex AL80 (CHF)—were used to fabricate 3D electrospun nanocomposite grafts. SEM analysis showed a homogeneous distribution of fibers, with slight differences in terms of average diameters as a function of the polymer used—(1.14 ± 0.18) µm for COT, and (1.33 ± 0.23) µm for CHF—that tend to disappear in the presence of MNPs—(1.26 ± 0.19) µm and (1.26 ± 0.213) µm for COT/NPs and CHF/NPs, respectively. TGA analyses confirmed the higher ability of CHF to entrap MNPs in the fibers—18.25% with respect to 14.63% for COT—while DSC analyses suggested an effect of MNPs on short-range rearrangements of hard/soft micro-domains of CHF. Accordingly, mechanical tests confirmed a decay of mechanical strength in the presence of MNPs with some differences depending on the matrix—from (6.16 ± 0.33) MPa to (4.55 ± 0.2) MPa (COT), and from (3.67 ± 0.18) MPa to (2.97 ± 0.22) MPa (CNF). The in vitro response revealed that the presence of MNPs did not negatively affect cell viability after 7 days in in vitro culture, suggesting a promising use of these materials as smart vascular grafts able to support the actuation function of vessel wall muscles. Full article

(This article belongs to the Section Polymer Applications)

► Show Figures

Figure 1

10 pages, 1819 KiB

Open AccessArticle

Design and Synthesis of Fe₃O₄-Loaded Polymer Microspheres with Controlled Morphology: Section II Fabrication of Walnut-like Superparamagnetic Polymer Microspheres

by Florence Acha, Talya Scheff, Nathalia DiazArmas and Jinde Zhang

Polymers 2025, 17(13), 1876; https://doi.org/10.3390/polym17131876 (registering DOI) - 5 Jul 2025

Abstract

A simple and innovative synthesis strategy was established to produce polymer microspheres with a distinctive walnut-like morphology, incorporating Fe₃O₄ nanoparticles within their structure. This was achieved through γ-ray-initiated mini-emulsion polymerization. To ensure high encapsulation efficiency, the surface of the Fe [...] Read more.

A simple and innovative synthesis strategy was established to produce polymer microspheres with a distinctive walnut-like morphology, incorporating Fe₃O₄ nanoparticles within their structure. This was achieved through γ-ray-initiated mini-emulsion polymerization. To ensure high encapsulation efficiency, the surface of the Fe₃O₄ nanoparticles was chemically altered to shift their wettability from hydrophilic to hydrophobic, enabling uniform dispersion within the monomer phase before polymerization. The formation of the walnut-like architecture was found to be significantly influenced by both the polymerization dynamics and phase separation, as well as the shrinkage of the crosslinked polymer network formed between the monomer and the resulting polymer. Divinylbenzene (DVB) was chosen as the monomer due to its ability to generate a mechanically stable polymer framework. The γ-ray irradiation effectively initiated polymerization while preserving structural coherence. A detailed analysis using FTIR, SEM, and TEM confirmed the successful fabrication of the Fe₃O₄-loaded polymer microspheres with their characteristic textured surface. Moreover, magnetic characterization via vibrating sample magnetometry (VSM) indicated pronounced superparamagnetic behavior and strong magnetic responsiveness, highlighting the potential of these microspheres for advanced biomedical applications. Full article

(This article belongs to the Section Innovation of Polymer Science and Technology)

► Show Figures

Figure 1

22 pages, 4077 KiB

Open AccessArticle

Strong Amphoteric Adsorption of Reactive Red-141 onto Modified Orange Peel Derivatives: Optimization, Characterization, and Mechanism

by Behlul Koc-Bilican, Ismail Bilican and Hakan Çelebi

Polymers 2025, 17(13), 1875; https://doi.org/10.3390/polym17131875 - 4 Jul 2025

Abstract

This study investigates the adsorption performance of Reactive Red-141 (ReR-141) using three modified orange peel derivatives: raw orange peel (ROP), oil-free orange peel (NOOP), and cellulose extract (CE). The adsorbents were prepared through sequential treatments and characterized by scanning electron microscopy, energy-dispersive X-ray [...] Read more.

This study investigates the adsorption performance of Reactive Red-141 (ReR-141) using three modified orange peel derivatives: raw orange peel (ROP), oil-free orange peel (NOOP), and cellulose extract (CE). The adsorbents were prepared through sequential treatments and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy to investigate their surface morphology and functional groups. Batch adsorption experiments were conducted under varying conditions of pH, temperature, time, and adsorbent amount. NOOP displayed the highest adsorption capacity (99.72% removal efficiency), followed by CE (86.99%) and ROP (77.55%), under optimal conditions. The adsorption kinetics followed a PSO model, while the equilibrium data were best described by Langmuir, indicating monolayer adsorption. Thermodynamic factors confirmed that the process was self-generated and primarily determined by physisorption. Desorption studies using 0.2 M NaOH demonstrated that NOOP retained 98.16% efficiency after three cycles, indicating its strong reusability. The adsorption mechanism is determined by different interactions, such as electrostatic forces, H-bonding, and π–π stacking. These findings suggest that orange peel derivatives, particularly NOOP, serve as optimal and environmentally sustainable adsorbents for the yield of ReR-141 from synthetic aqueous media. Full article

(This article belongs to the Section Biobased and Biodegradable Polymers)

► Show Figures

Figure 1

18 pages, 7280 KiB

Open AccessArticle

Bionic Bovine Achilles Tendon Collagen Composite Membrane Loaded with Anti-Inflammatory Kukoamine B Promotes Skin Wound Healing

by Ruting Luo, Yujie Mu, Le Zhao, Jinglin Hua, Lixin Cao, Danting Chen, Kun Li, Zhenkai Jin, Yanchuan Guo, Bing Zhang and Min Wang

Polymers 2025, 17(13), 1874; https://doi.org/10.3390/polym17131874 - 4 Jul 2025

Abstract

Skin is the first line of defence between the human body and the outside world, and it is constantly exposed to external injuries and wounds for a variety of reasons. Collagen is a structural protein of the extracellular matrix and an important component [...] Read more.

Skin is the first line of defence between the human body and the outside world, and it is constantly exposed to external injuries and wounds for a variety of reasons. Collagen is a structural protein of the extracellular matrix and an important component of the dermis. As a wound dressing, collagen not only provides nutrients to wounds but also enhances the immune response in the pre-healing phase, making it an excellent biomaterial for healing. In this study, we used electrospinning and freeze-drying technology to prepare a Bovine Achilles Tendon Collagen (BATC) electrospun composite membrane and a BATC freeze-dried composite membrane using BATC as a substrate supplemented with 16.7% Polyethylene oxide (PEO) and 0.2% Kukoamine B (KuB). The physicochemical properties and biocompatibility of the BATC composite membrane were verified via scanning electron microscopy, Fourier-transform infrared spectroscopy, and DSC analysis and by measuring the DPPH radical-scavenging capacity, water absorption, water retention, in vitro drug release, and extract cytotoxicity. The BATC composite membrane was found to have a significant effect on skin wound healing, especially in the middle stage of healing, in a mouse full-thickness skin injury model. The BATC/PEO/KuB electrospun composite membrane (EBPK) had the best capacity for promoting wound healing and can be used as a wound dressing for in-depth research and development, and KuB, a monomer component with a clear structure and mechanism of action, can be used as a candidate component of composite dressings. Full article

(This article belongs to the Section Biobased and Biodegradable Polymers)

► Show Figures

Figure 1

21 pages, 783 KiB

Open AccessReview

Machine Learning in Predicting and Optimizing Polymer Printability for 3D Bioprinting

by Junjie Yu, Danyu Yao, Ling Wang and Mingen Xu

Polymers 2025, 17(13), 1873; https://doi.org/10.3390/polym17131873 - 4 Jul 2025

Abstract

Three-dimensional (3D) bioprinting has emerged as a highly promising technology within the realms of tissue engineering and regenerative medicine. The assessment of printability is essential for ensuring the quality of bio-printed constructs and the functionality of the resultant tissues. Polymer materials, extensively utilized [...] Read more.

Three-dimensional (3D) bioprinting has emerged as a highly promising technology within the realms of tissue engineering and regenerative medicine. The assessment of printability is essential for ensuring the quality of bio-printed constructs and the functionality of the resultant tissues. Polymer materials, extensively utilized as bioink materials in extrusion-based bioprinting, have garnered significant attention from researchers due to the critical need for evaluating and optimizing their printability. Machine learning, a powerful data-driven technology, has attracted increasing attention in the evaluation and optimization of 3D bioprinting printability in recent years. This review provides an overview of the application of machine learning in the printability research of polymers for 3D bioprinting, encompassing the analysis of factors influencing printability (such as material and printing parameters), the development of predictive models, and the formulation of optimization strategies. Additionally, the review briefly explores the utilization of machine learning in predicting cell viability, evaluates the advanced nature and developmental potential of machine learning in 3D bioprinting, and examines the current challenges and future trends. Full article

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

24 pages, 6713 KiB

Open AccessArticle

Modelling and Optimisation of FDM-Printed Short Carbon Fibre-Reinforced Nylon Using CCF and RSM

by Qibin Fang, Jing Yu and Bowen Shi

Polymers 2025, 17(13), 1872; https://doi.org/10.3390/polym17131872 - 4 Jul 2025

Abstract

Nylon reinforced with short carbon fibres exhibits superior mechanical properties. Its use as a feedstock for fused deposition modelling (FDM) can extend its applications to consumer goods and industrial products. To investigate the flexural and impact properties of the FDM-printed short carbon fibre-reinforced [...] Read more.

Nylon reinforced with short carbon fibres exhibits superior mechanical properties. Its use as a feedstock for fused deposition modelling (FDM) can extend its applications to consumer goods and industrial products. To investigate the flexural and impact properties of the FDM-printed short carbon fibre-reinforced nylon, a central composite face-centred (CCF) design with four factors and three levels and the response surface method (RSM) were employed. The four primary process parameters are the extrusion and bed temperatures, printing speed, and layer thickness. The three investigated responses were the flexural strength, flexural modulus, and impact strength. Perturbation curves and contour plots were used to analyse the influences of the individual and two-way interactions of the response parameters, respectively. Second-order statistical models were constructed to predict and optimise the mechanical properties. The optimal comprehensive mechanical properties were determined using a desirability function combined with the entropy weighting method. The predicted results of best comprehensive mechanical properties are 169.881 MPa for the flexural strength, 9249.11 MPa for the flexural modulus, and 29.659 kJ∙m⁻² for the impact strength, achieved under the parameter combination of extrusion temperature of 318 °C, bed temperature of 90 °C, printing speed of 30 mm∙s⁻¹, and layer thickness of 0.1 mm. A small deviation between the predicted and experimental results indicated the high reliability of the proposed method. The optimal outcomes under the studied parameters showed higher robustness and integrity than previously reported results. Full article

(This article belongs to the Section Polymer Fibers)

► Show Figures

Figure 1

24 pages, 4729 KiB

Open AccessArticle

Formulation and Stability of Quercetin-Loaded Pickering Emulsions Using Chitosan/Gum Arabic Nanoparticles for Topical Skincare Applications

by Mathukorn Sainakham, Paemika Arunlakvilart, Napatwan Samran, Pattavet Vivattanaseth and Weeraya Preedalikit

Polymers 2025, 17(13), 1871; https://doi.org/10.3390/polym17131871 - 4 Jul 2025

Abstract

Natural polymer-based nanoparticles have emerged as promising stabilizers for Pickering emulsions, offering biocompatibility, environmental sustainability, and improved protection of active compounds. This study developed chitosan/gum arabic (CH/GA) nanoparticles as solid stabilizers for quercetin-loaded Pickering emulsions to enhance the stability and antioxidant bioactivity of [...] Read more.

Natural polymer-based nanoparticles have emerged as promising stabilizers for Pickering emulsions, offering biocompatibility, environmental sustainability, and improved protection of active compounds. This study developed chitosan/gum arabic (CH/GA) nanoparticles as solid stabilizers for quercetin-loaded Pickering emulsions to enhance the stability and antioxidant bioactivity of quercetin (QE), a plant-derived flavonoid known for its potent radical-scavenging activity but limited by oxidative degradation. A systematic formulation strategy was employed to evaluate the effects of CH/GA concentration (0.5–2.0% w/v), oil type (olive, soybean, sunflower, and coconut), and oil volume fraction (ϕ = 0.5–0.7) on emulsion stability. The formulation containing 1.5% CH/GA and olive oil at ϕ = 0.6 exhibited optimal physical and interfacial stability. Quercetin (0.1% w/w) was incorporated into the optimized emulsions and characterized for long-term stability, particle size, droplet morphology, rheology, antioxidant activity (DPPH), cytocompatibility, and intracellular reactive oxygen species (ROS) protection using HaCaT keratinocytes. The olive oil-based formulation (D1-QE) exhibited greater viscosity retention and antioxidant stability than its soybean-based counterpart (E2-QE) under both room temperature (RT) and accelerated heating–cooling (H/C) storage conditions. Confocal microscopy confirmed the accumulation of CH/GA nanoparticles at the oil–water interface, forming a dense interfacial barrier and enhancing emulsion stability. HPLC analysis showed that D1-QE retained 92.8 ± 0.5% of QE at RT and 82.8 ± 1.5% under H/C conditions after 30 days. Antioxidant activity was largely preserved, with only 4.7 ± 1.7% and 14.9 ± 4.8% loss of DPPH radical scavenging activity at RT and H/C, respectively. Cytotoxicity testing in HaCaT keratinocytes confirmed that the emulsions were non-toxic at 1 mg/mL QE and effectively reduced H₂O₂-induced oxidative stress, decreasing intracellular ROS levels by 75.16%. These results highlight the potential of CH/GA-stabilized Pickering emulsions as a polymer-based delivery system for maintaining the stability and functional antioxidant activity of QE in bioactive formulations. Full article

(This article belongs to the Special Issue Sustainable Biopolymer-Based Composites: Processing, Characterization, and Application II)

► Show Figures

Figure 1

11 pages, 6984 KiB

Open AccessArticle

Self-Assembly of Amphiphilic Comb-like Copolymers into Micelles and Vesicles in Solution

by Qiaoyue Chen, Kun Tian, Ruiqi Zhu, Mingming Ding and Zhanwen Xu

Polymers 2025, 17(13), 1870; https://doi.org/10.3390/polym17131870 - 4 Jul 2025

Abstract

Combining Brownian dynamics simulations and self-consistent field theory, we demonstrate that stable assembled structures, such as vesicles, toroidal micelles, bowl-like micelles, sheet-like micelles, non-spherical vesicles, and cylindrical micelles, are dependent on the molecular parameters of amphiphilic comb-like copolymers. Importantly, we find that vesicle [...] Read more.

Combining Brownian dynamics simulations and self-consistent field theory, we demonstrate that stable assembled structures, such as vesicles, toroidal micelles, bowl-like micelles, sheet-like micelles, non-spherical vesicles, and cylindrical micelles, are dependent on the molecular parameters of amphiphilic comb-like copolymers. Importantly, we find that vesicle formation involves two intermediate states, sheet-like and bowl-like micelles, and the difference in their free energies is minimal, which illustrates the coexisting phase between them. Moreover, the assembled vesicles can be modulated in the membrane thickness with overall size, unchanged only by adjusting the backbone length. We also demonstrate the coexistence of toroidal and cylindrical micelles because neither structure has a significant advantage over the other in free energy. Our work points out how to obtain different morphologies by adjusting the molecular parameters of amphiphilic comb-like copolymers, instilling confidence in their potential for stable drug encapsulation and enhanced targeted drug delivery. Full article

(This article belongs to the Special Issue Advances and Applications of Block Copolymers II)

► Show Figures

Figure 1

24 pages, 7709 KiB

Open AccessArticle

Quaternized Polysulfones as Matrix for the Development of Broad-Spectrum Antimicrobial Coatings for Medical Devices

by Oana Dumbrava, Irina Rosca, Daniela Ailincai and Luminita Marin

Polymers 2025, 17(13), 1869; https://doi.org/10.3390/polym17131869 - 3 Jul 2025

Abstract

The development and application of antimicrobial coatings has become increasingly important in both medical and industrial settings due to the rising threat of microbial contamination and antibiotic resistance. This paper focuses on the formulation, characterization, and investigation of coatings based on quaternized polysulfone, [...] Read more.

The development and application of antimicrobial coatings has become increasingly important in both medical and industrial settings due to the rising threat of microbial contamination and antibiotic resistance. This paper focuses on the formulation, characterization, and investigation of coatings based on quaternized polysulfone, which are designed to encapsulate two broad-spectrum antimicrobial drugs with complementary activity, amphotericin B (AmB) and norfloxacin (NFX), with the primary aim of inhibiting pathogen colonization on surgical instruments. Structural characterization using FTIR, ¹H-NMR, and UV-Vis spectroscopy, along with supramolecular analysis via X-ray diffraction and polarized optical microscopy (POM), revealed strong physical interactions between the drugs and the quaternized polysulfone matrix. Scanning electron microscopy (SEM) confirmed a uniform distribution of the antimicrobial agents within the polymeric matrix. Surface wettability, assessed through water contact angle measurements, indicated moderate hydrophilicity (70–90°). The coatings also exhibited notable antioxidant activity, showing a 12-fold increase in DPPH radical inhibition compared to the control. Furthermore, all formulations demonstrated strong antimicrobial efficacy against three reference strains frequently associated with hospital-acquired infections, S. aureus, E. coli, and C. albicans, with inhibition zones ranging from 32 to 39.67 mm for bacterial strains and 13.86 to 20.86 mm for C. albicans. These data points indicate that these materials may be useful as antimicrobial coatings. Full article

(This article belongs to the Special Issue Polymer Coatings for High-Performance Applications)

► Show Figures

Graphical abstract

16 pages, 2087 KiB

Open AccessArticle

Predictive Modelling and Optimisation of Rubber Blend Mixing Using a General Regression Neural Network

by Ivan Kopal, Ivan Labaj, Juliána Vršková, Marta Harničárová, Jan Valíček, Alžbeta Bakošová, Hakan Tozan and Ashish Khanna

Polymers 2025, 17(13), 1868; https://doi.org/10.3390/polym17131868 - 3 Jul 2025

Abstract

This paper presents an intelligent predictive system designed to support real-time decision making in the control of rubber blend mixing processes. The core of the system is a General Regression Neural Network (GRNN), which accurately predicts key process parameters, such as viscosity (expressed [...] Read more.

This paper presents an intelligent predictive system designed to support real-time decision making in the control of rubber blend mixing processes. The core of the system is a General Regression Neural Network (GRNN), which accurately predicts key process parameters, such as viscosity (expressed as torque), temperature, and energy consumption across varying masses of the processed material. The model can evaluate the mixing progress based on the initial 10% of input data, allowing early intervention and process optimisation. Experimental validation was conducted using a Brabender Plastograph EC Plus with a natural rubber-based blend in the mass range of 60–75 g. The GRNN kernel width parameter (σ) was optimised through a 10-fold cross-validation. High predictive accuracy was confirmed by values of the coefficient of determination (R²) approaching 1, and consistently low values of the root mean square error (RMSE). This system offers a robust and scalable solution for intelligent process control, productivity enhancement, and quality assurance across diverse industrial applications, beyond rubber blending. Full article

(This article belongs to the Special Issue Artificial Intelligence in Polymers)

► Show Figures

Figure 1

20 pages, 15028 KiB

Open AccessArticle

Development and Characterization of Self-Adhesive Polymeric Films with Antiallergic Effect

by Ioana Savencu, Sonia Iurian, Cătălina Bogdan, Valentin Toma, Rareș Știufiuc and Ioan Tomuță

Polymers 2025, 17(13), 1867; https://doi.org/10.3390/polym17131867 - 3 Jul 2025

Abstract

This study aimed to design self-adhesive cutaneous films with an antiallergic effect using a Design of Experiments approach. The active pharmaceutical ingredient (API) was diphenhydramine hydrochloride (DPH). A full factorial experimental design with three factors and two levels was created. The factors were [...] Read more.

This study aimed to design self-adhesive cutaneous films with an antiallergic effect using a Design of Experiments approach. The active pharmaceutical ingredient (API) was diphenhydramine hydrochloride (DPH). A full factorial experimental design with three factors and two levels was created. The factors were the polyvinyl alcohol (PVA) ratio, the polyacrylic acid (PAA) ratio, and the type of plasticizer. The responses evaluated were hardness, deformation at hardness, adhesive force, and in vitro DPH release profile. Eleven formulations were generated, prepared in two steps via solvent casting, and characterized in terms of mechanical and adhesive properties, as well as the in vitro DPH release profile. The PVA ratio had the most significant impact on the responses, followed by PEG 400 and PEG 4000. Four film formulations were investigated using Raman spectroscopy, which revealed that the API was distributed in both the base and adhesive layers. Consequently, an optimal formulation was prepared and characterized. Good mechanical properties (a hardness of 463.7 g and a deformation at hardness of 16.56 mm) and an increased adhesive force (76 g) were observed, while the DPH was released up to 68% over 12 h. In conclusion, a novel self-adhesive film was developed, which may enhance patients’ adherence to local antiallergic treatment. Full article

(This article belongs to the Section Polymer Membranes and Films)

► Show Figures

Graphical abstract

16 pages, 2745 KiB

Open AccessArticle

Next-Generation Nafion Membranes: Synergistic Enhancement of Electrochemical Performance and Thermomechanical Stability with Sulfonated Siliceous Layered Material (sSLM)

by Valeria Loise and Cataldo Simari

Polymers 2025, 17(13), 1866; https://doi.org/10.3390/polym17131866 - 3 Jul 2025

Abstract

Nafion, while a benchmark proton exchange membrane (PEM) for fuel cells, suffers from significant performance degradation at elevated temperatures and low humidity due to dehydration and diminished mechanical stability. To address these limitations, this study investigated the development and characterization of Nafion nanocomposite [...] Read more.

Nafion, while a benchmark proton exchange membrane (PEM) for fuel cells, suffers from significant performance degradation at elevated temperatures and low humidity due to dehydration and diminished mechanical stability. To address these limitations, this study investigated the development and characterization of Nafion nanocomposite membranes incorporating sulfonated silica layered materials (sSLMs). The inherent lamellar structure, high surface area, and abundant sulfonic acid functionalities of sSLMs were leveraged to synergistically enhance membrane properties. Our results demonstrate that sSLM incorporation significantly improved ion exchange capacity, water uptake, and dimensional stability, leading to superior water retention and self-diffusion at higher temperatures. Critically, the nanocomposite membranes exhibited remarkably enhanced proton conductivity, particularly under demanding conditions of 120 C and low relative humidity (i.e., 20% RH), where filler-free Nafion largely ceases to conduct. Single H₂/O₂ fuel cell tests confirmed these enhancements, with the optimal sSLM-Nafion nanocomposite membrane (N-sSLM₅) achieving a two-fold power density improvement over pristine Nafion at 120 C and 20% RH (340 mW cm⁻² vs. 117 mW cm⁻² for Nafion). These findings underscore the immense potential of sSLM as a functional filler for fabricating robust and high-performance PEMs, paving the way for the next generation of fuel cells capable of operating efficiently under more challenging environmental conditions. Full article

(This article belongs to the Section Polymer Membranes and Films)

► Show Figures

Figure 1

21 pages, 8987 KiB

Open AccessArticle

Modeling and Compensation Methods for Trajectory Errors in Continuous Fiber-Reinforced Thermoplastic Composites Using 3D Printing

by Manxian Liu, Sheng Qu, Shuo Li, Xiaoqiang Yan, Wei Li and Yesong Wang

Polymers 2025, 17(13), 1865; https://doi.org/10.3390/polym17131865 - 3 Jul 2025

Abstract

Defects arising from the 3D printing process of continuous fiber-reinforced thermoplastic composites primarily hinder their overall performance. These defects particularly include twisting, folding, and breakage of the fiber bundle, which are induced by printing trajectory errors. This study presents a follow-up theory assumption [...] Read more.

Defects arising from the 3D printing process of continuous fiber-reinforced thermoplastic composites primarily hinder their overall performance. These defects particularly include twisting, folding, and breakage of the fiber bundle, which are induced by printing trajectory errors. This study presents a follow-up theory assumption to address such issues, elucidates the formation mechanism of printing trajectory errors, and examines the impact of key geometric parameters—trace curvature, nozzle diameter, and fiber bundle diameter—on these errors. An error model for printing trajectory is established, accompanied by the proposal of a trajectory error compensation method premised on maximum printable curvature. The presented case study uses CCFRF/PA as an exemplar; here, the printing layer height is 0.1~0.3 mm, the fiber bundle radius is 0.2 mm, and the printing speed is 600 mm/min. The maximum printing curvature, gauged by the printing trajectory of a clothoid, is found to be 0.416 mm⁻¹. Experimental results demonstrate that the error model provides accurate predictions of the printed trajectory error, particularly when the printed trajectory forms an obtuse angle. The average prediction deviations for line profile, deviation kurtosis, and deviation area ratio are 36.029%, 47.238%, and 2.045%, respectively. The error compensation effectively mitigates the defects of fiber bundle folding and twisting, while maintaining the printing trajectory error within minimal range. These results indicate that the proposed method substantially enhances the internal defects of 3D printed components and may potentially be applied to other continuous fiber printing types. Full article

(This article belongs to the Special Issue Advances in Polymers Science and Technology: From Nano-Engineering to Multifunctional Applications)

► Show Figures

Figure 1

19 pages, 11146 KiB

Open AccessArticle

Effect of Build Orientation on Surface Finish and Hydrodynamic Stability of Inkjet 3D-Printed Microfluidic Channels

by Emanuela Cutuli, Lorena Saitta, Nunzio Tuccitto, Gianluca Cicala and Maide Bucolo

Polymers 2025, 17(13), 1864; https://doi.org/10.3390/polym17131864 - 3 Jul 2025

Abstract

This study examined the effect of build orientation on the surface finish of micro-optofludic (MoF) devices fabricated via a polydimethylsiloxane (PDMS)-based 3D-printing primary–secondary fabrication protocol, where an inkjet 3D-printing technique was implemented. The molds (i.e., primaries) for fabricating the MoF devices were 3D-printed [...] Read more.

This study examined the effect of build orientation on the surface finish of micro-optofludic (MoF) devices fabricated via a polydimethylsiloxane (PDMS)-based 3D-printing primary–secondary fabrication protocol, where an inkjet 3D-printing technique was implemented. The molds (i.e., primaries) for fabricating the MoF devices were 3D-printed in two orientations: along

X Y

(Dev-1) and across

Y X

(Dev-2) the printhead direction. Next, the surface finish was characterized using a profilometer to acquire the primary profile of the surface along the microchannel’s edge. The results indicated that the build orientation had a strong influence on the latter, since Dev-1 displayed a tall and narrow Gaussian distribution for a channel width of 398.43 ± 0.29 µm; Dev-2 presented a slightly lower value of 393.74 ± 1.67 µm, characterized by a flat and broader distribution, highlighting greater variability due to more disruptive, orthogonally oriented, and striated patterns. These results were also confirmed by hydrodynamically testing the two MoF devices with an air–water slug flow process. A large experimental study was conducted by analyzing the mean period trend in the slug flow with respect to the imposed flow rate and build orientation. Dev-1 showed greater sensitivity to flow rate changes, attributed to its smoother, more consistent microchannel geometry. The slightly narrower average channel width in Dev-2 contributed to increased flow velocity at the expense of having worse discrimination capability at different flow rates. This study is relevant for optimizing 3D-printing strategies for the fabrication of high-performance microfluidic devices, where precise flow control is essential for applications in biomedical engineering, chemical processing, and lab-on-a-chip systems. These findings highlight the effect of microchannel morphology in tuning a system’s sensitivity to flow rate modulation. Full article

(This article belongs to the Section Polymer Analysis and Characterization)

► Show Figures

Figure 1

Journal Description

Polymers

Latest Articles

Journal Menu

Journal Browser

Highly Accessed Articles

Latest Books

E-Mail Alert

News

Topics

Conferences

Special Issues

Topical Collections

Further Information

Guidelines

MDPI Initiatives

Follow MDPI