Advances in Polymer Technology最新文献

This study investigated the preparation and self-association behavior in water of amphiphilic statistical copolymers, poly(vinyl alcohol-co-vinyl laurate) [P(VA/LA_x)] (x = 0, 7, 25, 32, and 41 mol%), composed of hydrophilic vinyl alcohol (VA) and hydrophobic vinyl LA units. These copolymers were synthesized via reversible addition–fragmentation chain transfer (RAFT) radical polymerization. Due to their amphiphilic nature, P(VA/LA_x) formed micelles in aqueous solution. Dynamic light scattering (DLS) measurements showed that both the hydrodynamic radius (R_h) and light scattering intensity (LSI) values increased with increasing LA content, indicating that enhanced hydrophobicity promoted the formation of larger micelles. The copolymers exhibited unimodal size distributions with R_h values ranging from 57.3 to 100.4 nm, suggesting the formation of interpolymer aggregates driven by hydrophobic interactions among pendant lauryl units. Transmission electron microscopy (TEM) confirmed the formation of spherical micelles, with sizes consistent with R_h values. Static light scattering (SLS) measurements further revealed that the aggregation number increased with higher LA content. The critical micelle concentration (CMC), determined using a pyrene fluorescence probe, decreased with increasing LA composition, ranging from 3.3 to 0.62 × 10⁻³ g/L. These findings demonstrate that amphiphilic P(VA/LA_x) copolymers form stable interpolymer micelles in water, with tunable properties governed by their hydrophobic content.

The ability of polymeric materials to maintain their mechanical properties in humid environments is important for products across many industries, including paints and coatings, packaging, and personal care industries, amongst others. In this study, we utilize humidity-controlled dynamic mechanical analysis (RH-DMA) to evaluate the mechanical behavior of film-forming sulfopolyester polymers subjected to sustained stress in high-humidity environments. Our results demonstrate how these sulfopolyester polymer films respond to both oscillatory and creep deformations when exposed to high humidity. Our aim is to link their mechanical properties under elevated humidity conditions to their potential use as film formers that maintain hair curl retention in personal care applications. We propose the use of a force-controlled creep test using a 0.02 N load to simulate the gravitational force relevant to a 2 g hair sample. Under these testing conditions, we found the material with the highest Tg resulted in a 0.3% elongation after 5 h at 90% RH, which would suggest durable performance in hair styling applications. The results highlight the value of RH-DMA as a predictive tool for screening film formers in the development of personal care products.

Aerogel-modified polyamide 6 draw textured yarns (AE/PA6 DTYs) were prepared through melt spinning and subsequent drawing processes. The influence of draw temperature on the structural characteristics and mechanical properties of AE/PA6 DTYs were thoroughly investigated. The results demonstrated that the drawing process significantly improved the molecular the orientation and crystallinity of AE/PA6 DTYs. When the draw temperature was set at 148°C, the AE/PA6 DTY exhibited a higher content of hydrogen-bonded groups, an increased proportion of the α-form crystals, and enhanced crystallinity. These structural features contributed to superior tensile strength and crimp performance compared to samples processed at draw temperatures ranging from 143 to 173°C. Additionally, at this optimal draw temperature, the crimp contraction and crimp stability reached 51.62% and 66.69%, respectively, with a tensile strength of 4.36 cN/dtex. These findings provide meaningful insights and practical references for the optimization of the false twist texturing process for AE/PA6 DTYs.

Polymer–lipid hybrid (PLH) nanoparticles have become an appealing therapeutic delivery system owing to their special properties. These nanoparticles are made with polymer and lipid components and have garnered significant interest across therapeutic applications. The combined properties of the polymers and lipids enable improved drug delivery by enhancing the stability, biocompatibility, and controlled drug release of the nanoparticle. The versatility of this form of drug carrier, including biomimetic and biocompatible features, allows the encapsulation of a wide range of therapeutic agents, including hydrophilic and hydrophobic compounds, proteins, and nucleic acids. These drug carriers can be modified and adapted to target the desired site of action, specific cells, and tissues, while minimizing the possibility of off-target and adverse effects. Thus, this review provides an in-depth analysis into PLH nanoparticles as a novel delivery system, their inherent characteristics, the functionalization strategies, and their wide applications, while providing their potential for future possibilities.

Drug-eluting embolic microspheres are receiving increasing attention in transarterial chemoembolization (TACE), which is one of the most important approaches for the treatment of unresectable hepatocellular carcinoma (HCC). However, currently most commercial microspheres are radiolucent and their position in vivo needs to be indirectly monitored by X-ray angiography. In addition, microspheres reflux may cause nontargeted embolism. The aim of this study is to develop an inherently radiopaque embolic agent capable of delivering drugs and enhancing the embolic effect. In this study, using emulsification (S/W/O) and photocrosslinking, the mixture of methacrylated polyvinyl alcohol (PVAMA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and barium sulfate was prepared into BaSO₄/PVA/AMPS beads. Barium sulfate act as computed tomography (CT) contrast agent, while sulfonic acid groups give the hydrogel beads drug loading and sustained release properties. The embolic performance of beads is enhanced by loading etamsylate. The results indicate that the prepared beads are radiopaque, biocompatible, with good drug sustained release performance. In vivo embolization and imaging properties were demonstrated by a rabbit ear central artery embolization model.

Additive manufacturing (AM) via material extrusion (MEx) offers customizable, cost-effective routes to patient-specific bone scaffolds, but balancing mechanical performance, production efficiency, and pore architecture in biodegradable composites remains challenging. In this study, we compounded 12 wt% silicon into polylactic acid (Si–PLA) filament and evaluated 12 MEx parameter clusters varying nozzle temperature (200–220 °C), bed temperature (70–90°C), infill patterns (hexagonal/line/triangular), infill density (60%–80%), print/travel speeds (40–60 mm/s), and firstlayer thickness (2–4 mm) using a SpiceLogic analytic hierarchy process (AHP) framework. Nine criteria spanning estimated vs. actual print time, ultimate tensile/flexural strength and moduli, and morphological quality (pore uniformity, surface defects, and infill fidelity) were weighted and ranked. The A4 cluster (200°C/70°C, line infill, 60%, 60 mm/s speeds, and 2 mm layer) emerged as optimal, delivering a 4.3 MPa tensile strength (+12%) and 17.2 MPa flexural strength (+15%) while reducing print time by 10%. Sensitivity analysis confirmed ranking robustness across ±10% weight variations. This decision science approach not only outperformed traditional Taguchi/response surface methodology (RSM) methods in multiresponses’ trade-off but also provides a scalable pathway for translating Si–PLA scaffold fabrication from lab to commercial production.

Hybrid jute–banana fiber-reinforced recycled high-density polyethylene (rHDPE) composites present a sustainable alternative for achieving improved mechanical performance and ecological durability. This study addresses the challenge of simultaneously optimizing flexural and impact properties along with structural integrity by employing a novel (0°/90°/0°/90°) stacking configuration using both plasma-treated and untreated fiber preforms. Composites were fabricated through compression molding, placing rHDPE sheets strategically within a four-layer fiber stack and applying 5-ton pressure at 160°C for 15 min, followed by a 24-h curing period. Plasma treatment drastically influenced the adhesion of fiber and matrix, leading to an increased impact strength and altered behavior of water absorption. The greatest impact strength of 31.86 kJ/m²—a 45.4% improvement over its untreated counterpart—was found in the plasma-treated hybrid composite (plasma jute–banana composite [PJBC]) with a 7.6% flexural strain, signifying improved energy dissipation and ductility. However, flexural strength in hybrid composites decreased marginally (from 21.3 to 20.3 MPa) due to increased surface brittleness. Plasma treatment improved water absorption in jute composites (0.13%) via increased porosity, but hybridization minimized the effect to yield balanced moisture absorption and mechanical properties. The synergistic combination of jute stiffness and banana flexibility in hybrid form, with plasma-induced surface activation, resulted in composites with optimal structural integrity and sustainability. These findings demonstrate the viability of plasma-treated hybrid rHDPE composites for resource-efficient application in packaging, automotive, and construction sectors, in line with the goal of the circular economy.

The growing demand for personalized biomedical devices positions polylactic acid (PLA) as a useful material because it is biodegradable and biocompatible while being easily processed by additive manufacturing. This study seeks toward optimization of key process parameters in fuzed filament fabrication (FFF). Improving the mechanical integrity and adaptability of biomedical-grade PLA components is the goal. Researchers systematically designed experiments that evaluated how four critical FFF parameters, layer thickness, wall thickness, infill density, along with infill pattern, influence tensile strength and fatigue life. For fabricated PLA specimens, standardized tensile tests in addition to low-cycle fatigue tests were used through varying combinations regarding these parameters. The results demonstrated that a layer that was 0.3 mm thick greatly improved fatigue life (1099 cycles) as well as tensile strength (39.8 MPa), while thinner layers performed worse. Wall thicknesses upto 3 mm improved fatigue performance however tensile strength gains lessened with later increases. At the 0.75 infill density, the mechanical performance was optimal (fatigue life: 1070 cycles, tensile strength: 39.6 MPa) but lower densities decreased durability. The grid structure has provided for the best balance between the strength and the fatigue resistance among all the infill patterns. It had better performance than Tri-hexagon and gyroid structures. One-way analysis of variance (ANOVA), that is a statistical validation, confirmed the importance of layer thickness and infill density for the mechanical outcomes at p < 0.0001. These findings suggest PLA components suitable for load bearing and bioresorbable medical applications can be yielded by careful tuning of FFF parameters. The researchers did study the issue for laying the groundwork. Engineers are allowed by this work to develop smart, patient-specific PLA composites later in biomedical engineering.

This study incorporates celery pulp microfibers into styrene–ethylene–butylene–styrene (SEBS) composites, aiming to generate value from waste. The study addresses compatibility issues between hydrophilic fibers and the hydrophobic polymer matrix by using ethylene vinyl alcohol (EVOH) as a compatibilizer. Results show significant enhancement of mechanical properties in EVOH-compatibilized composites. The compatibilized fiber composite (SE-05) exhibits higher tensile strength (7.437 MPa) and Young’s modulus (63.766 MPa) compared to the uncompatibilized composite (SEBS/cellulose [SC]-05) and SEBS matrix. Both composites exhibit decreased elongation at break with increased fiber loading. Fourier transform infrared spectroscopy (FTIR) analysis indicates the incorporation of EVOH and its interaction with cellulose microfibers, as evidenced by enhanced O─H and C─O stretching regions. Scanning electron microscopy (SEM) micrographs further show improved fiber dispersion and reduced pull out in EVOH-containing composites, suggesting enhanced interfacial adhesion and load transfer. The composites demonstrate enhanced dynamic mechanical behavior, with higher storage modulus and glass transition temperature than the matrix polymer. These improvements suggest the potential of eco-friendly, sustainable composites for diverse applications, including biomedical and packaging industries. By utilizing cellulosic fibers which obtained from celery pulp residue, this study creates advanced polymeric materials with enhanced properties through melt mixing and molding techniques. This approach highlights an innovative solution to environmental concerns while adding value to waste materials.

The study aimed to prepare alginate–carboxymethylcellulose (ALG–CMC) composite membranes containing natamycin (NA) and tetracycline hydrochloride (TCH) for use as antimicrobial wound dressings. The membranes were fabricated using a solvent casting method with varying mass ratios of NA:TCH (0:1, 0.5:1, 1:1, and 2:1) and subsequently cross-linked with calcium chloride. Scanning electron microscopy (SEM) analysis demonstrated that the membranes were structures without visible NA crystals, indicating good compatibility between the antimicrobial agents and the polymer matrix. Fourier transform infrared spectroscopy results suggested that the interactions between the bioactive compounds and the ALG–CMC matrix were relatively weak. The incorporation of antimicrobial agents did not cause significant changes in the swelling behavior (~603%–636%), weight loss profile (75%–77%), tensile strength (~22−24 MPa), and water vapor transmission rate (WVTR; 1.3–1.5 mg/cm²·h) of the membranes. The agar diffusion assay showed that the M-0.5 membrane formulation demonstrated inhibition zones of 2.1 cm for Staphylococcus aureus, 1.3 cm for Escherichia coli, and 1.6 cm for Candida albicans. The release profile of TCH followed a diffusion-degradation mechanism, and cytotoxicity assessments indicated that M-0.5 exhibited ~87% cell viability, indicating noncytotoxicity to mouse fibroblast cells. These results demonstrate that ALG–CMC composite membranes containing NA and TCH have the potential to be useful antimicrobial wound dressing materials.