Journal of Polymer Research最新文献

In this study, to address the issues of uneven dispersion and fracture damage of glass fibers (GF) during the preparation of traditional polyamide-based GF composites, a PA9T prepolymer (molecular weight: 2200; relative viscosity: 1.04) was innovatively adopted as the matrix. PA9T/GF composites were then fabricated by combining three-screw extrusion with melt viscosity-enhanced in-situ polymerization technology. Compared with finished polyamides, the low melt viscosity of the PA9T prepolymer provides a low-shear-stress dispersion environment for GF, which effectively maintains the consistency of fiber aspect ratio—fiber length concentrates in the range of 1.75–3.25 mm even at high screw speeds. By regulating the screw rotation speed (50–100 r/min) and feeding rate (2.0–3.0 Hz), uniform dispersion and interfacial compatibility of GF in the PA9T matrix were achieved. The results show that the composite prepared via this process exhibits a maximum tensile strength of 213.5 MPa and bending strength of 268.4 MPa, and the performance retention rate exceeds 84% after 2000 h of thermo-oxidative aging at 180 ℃. Additionally, it demonstrates excellent fatigue life (achieving 88.2 × 10⁴ cycles under a stress of 70 MPa) and creep resistance (exhibiting only 3.653% strain under a 90 MPa load for 1000 h). This study provides a new path for the preparation of high-performance polyamide-based composites based on prepolymer melt viscosity enhancement in-situ polymerization.

In this study, fluorine-free Si-based polyurethane (Si-PU) membranes were prepared via electrospinning. The electrospinning parameters were optimized in the presence of sodium chloride (NaCl) as an electrolyte, thereby affecting jet formation, stability, and nanofiber fineness. Four different amounts of Si nanoparticles (SNPs) (0.5, 1, 1.5, and 2 wt% in relation to PU) were dispersed in the polymer solution, and the effect on the static water contact angle, water vapor transfer, and the mechanical properties of the membranes was investigated. The results indicated that under the applied condition, 2 wt% of SNPs resulted in the highest hydrophobicity (105 ± 9°), appropriate breathability (2100 ± 68 g m^− 2 day^− 1), and the least fiber diameter (232 ± 57 nm). The fibrous membrane obtained from PU, NaCl, and SNPs could be a promising candidate for various applications including protective clothing, sportswear and etc.

This study explores the impact of using maleated PBAT (PBAT-g-MA) as a compatibilizer on the thermal and mechanical characteristics of composites made from polybutylene adipate-co-terephthalate (PBAT), Palm Fronds (PF) and Palm Stearin (PS). The issue arises from the use of single-use plastics which is non-biodegradable and raises concern for the environment. Additionally, the insufficient use of OPF PS, and PBAT-g-MA restricts the potential benefits they could offer. The research aims to improve the thermal and mechanical properties of PBAT/PF/PS blend by using PBAT-g-MA which includes enhancing the tensile strength, elongation, and thermal stability of the composite. In this research, a biodegradable composite blend was created by blending PBAT with PF and PS as a filler and subsequently incorporating PBAT-g-MA as a compatibilizer. The PBAT, PF, PS and PBAT-g-MA mixture was melted using an internal mixer. The result indicates that adding PBAT-g-MA significantly improved tensile strength and elongation at break, while reducing Young’s modulus. Thermal analysis showed a slight reduction in initial thermal stability with increasing PBAT-g-MA but demonstrated more uniform thermal degradation. Thus, these findings show that PBAT-g-MA can be an effective compatibilizer to enhance the mechanical and thermal properties of PBAT/PF/PS composites.

This study explores the mechanical, fatigue, creep, and water absorption properties of silane-treated epoxy composites reinforced with natural pineapple fiber and collagen powder derived from tuna fish skin. The use of these renewable materials promotes sustainability while enhancing performance without compromising strength, making the composites suitable for marine, automotive, aerospace, packaging, biomedical, and infrastructure applications. Surface treatment with 3-Aminopropyltrimethoxysilane (3-APTMS) significantly improves fiber-matrix bonding, resulting in stronger interfacial adhesion and more efficient load transfer. Specimen D (40% fiber, 3% collagen) showed the best mechanical and fatigue performance, with a tensile strength of 147 MPa and fatigue life of 24,179 cycles at 25% ultimate tensile strength (UTS), due to the balanced fiber and filler content that enhances load transfer and crack resistance. In contrast, Specimen E (40% fiber, 5% collagen) exhibited superior creep resistance (0.0062 strain at 5000 s) and the highest water absorption (0.043%), attributed to the hydrophilic nature of the higher collagen content. Scanning electron microscope (SEM) analysis confirmed improved fiber-matrix adhesion in treated specimens, with evidence of fiber breakage supporting efficient load transfer. However, higher filler content occasionally led to agglomeration, affecting mechanical properties. Overall, the study presents a promising approach to creating sustainable, high-performance composites using natural reinforcements.

In this study, N,N-diallyl-3-aminopropionic acid methyl ester (monomer N) was synthesized from diallylamine and methyl acrylate by the Michael addition reaction. The EPEG-type polycarboxylate superplasticizer PCE-N were prepared by free-radical polymerization of ethylene glycol monovinyl polyoxyethylene ether (EPEG) monomer with acrylic acid (AA), monomer N and AMPS in a H₂O₂-Vc redox initiator system. The synthesis parameters of PCE-N were investigated using single-factor experimental method, and the molecular structures were characterized by FT-IR, NMR and GPC techniques, and the mechanistic investigations of PCE-N were carried out by means of techniques such as the Zeta potential, optical microscopy, total organic carbon (TOC), X-ray photoelectron spectroscopy (XPS) and rheological properties. The optimal synthesis process parameters were obtained through the cement slurry fluidity tests: m(H₂O₂): m(EPEG) = 1.5%, m(Vc): m(EPEG) = 0.5%, m(MPA): m(EPEG) = 0.4%, n(AA): n(EPEG) = 3.5:1, n(monomer N): n(EPEG) = 0.5:1, n(AMPS): n(EPEG) = 0.4:1, reaction temperature: 30 °C, reaction time: 3.5 h, here m, n denote the mass ratio and molar ratio, respectively. The performance test results of PCE-N are as follows: 28.89% water reduction for mortar, the concrete compressive strengths are 26.6 MPa (3-day), 30.7 MPa (7-day) and 40.9 MPa (28-day), respectively, which imply that the PCE-N has excellent dispersion, water reduction and compression resistance properties. The results of the mechanistic study showed that the excellent water reduction and dispersion properties of PCE-N were attributed to both the electrostatic repulsion effect and the steric hindrance effect.

Arecanut organic residue (AR) incorporated polyvinyl alcohol (PVA)-chitosan (CH) films were successfully synthesized using the solvent casting method, aiming to enhance structural rigidity and dielectric performance. The novelty of this work lies in utilizing AR, a sustainable agricultural byproduct, as a natural functional additive to enhance the dielectric and thermal stability of PVA–chitosan blends. This eco-friendly approach introduces a biogenic interfacial modifier that improves polymer compatibility and performance without relying on synthetic fillers or chemical cross-linkers. FTIR spectra revealed the existence of cross-linking between PVA, chitosan and AR. Thermogravimetric analysis revealed that AR-PVA-CH films exhibited enhanced thermal stability compared to pure PVA, chitosan and PVA-CH blend. The dielectric constant, dielectric loss, DC conductivity, polarization and permittivity of pure PVA, pure chitosan, PVA-CH and AR-PVA-CH films were analysed in the frequency range from 100 Hz to 100 kHz. The optimized formulation (AR-C4) exhibited a maximum dielectric constant of 224.31 at 1 kHz, significantly higher than that of the pristine PVA–CH blend. The improvement in thermal stability has also been emphasized by indicating the increase in the T₅₀ value from 279.66 °C for PVA–CH to 358.37 °C for AR-C4. Furthermore, the enhancement in AC conductivity from 1.23 × 10⁻¹⁰ S/m for the PVA–CH blend to 5.93 × 10^–8 S/m for AR-C5 has been mentioned, demonstrating the synergistic influence of arecanut residue on charge transport and interfacial polarization. This research showcases that AR-induced structural changes in PVA-chitosan films lead to a notable improvement in their dielectric properties, making them promising candidates for advanced dielectric and thermal applications.

The linear structure, narrow molecular weight distribution, and low molecular weight of poly (butylene succinate) (PBS) result in poor melt viscoelasticity, which significantly affects its supercritical CO₂ foaming performance. In this paper, benzoyl peroxide (BPO) was introduced into PBS via reactive extrusion to prepare PBS with branched structure. Molecular weight test results showed that the molecular weight of PBS increased with increasing BPO concentration, from 103,877 g/mol to 181,409 g/mol. The results of shear and extensional rheology indicated that increasing BPO concentration enhanced the branching degree of PBS and promoted strain hardening behavior. Supercritical CO₂ foaming results showed that the foaming performance of the modified PBS has been significantly improved. The cells are regular and uniform, and the expansion ratio can reach up to 31.9 times, while the unmodified PBS can only reach up to 10.1 times. The method used in this paper is simple, efficient and does not form gel formation, deepening the understanding of the foaming behavior of PBS, and has significant industrial application value for the preparation of PBS materials suitable for foaming.

In the area of smart materials, self-healing polymer matrices have been the focus of study ever since they were developed. They can self-repair minor fractures and are provided with self-diagnostic capabilities. A lot of investigation has been done on polymeric hydrogels as materials for biomedical uses. Nevertheless, they are naturally specified by specialties such as lower mechanical strength and weak stimulus resistance. Because it can restore its previous mechanical properties by reforming its shape, injectability, and stretchability, it is more stable and long-lasting. This review focuses on the different extrinsic and intrinsic self-healing mechanisms of these hydrogels, covalent as well as non-covalent, how to estimate their self-healing capabilities, and how they are used in drug delivery, wound healing, cell encapsulation, and sensors.

Biopolymers have emerged as sustainable and versatile alternatives to synthetic polymers due to their biodegradability, biocompatibility, and environmental friendliness. Among these, chitin has gained considerable attention for its broad spectrum of biological activities, particularly its antimicrobial potential. Chitin and its derivatives exhibit inherent antimicrobial properties attributed to their cationic nature and ability to disrupt microbial cell membranes. Over the years, extensive efforts have been made to enhance the antimicrobial efficacy of chitin-based materials through various modification strategies, including physical, chemical, and biological approaches, as well as through nanotechnology and the incorporation of antimicrobial agents. This review provides a comprehensive analysis of recent advancements (2020–2025) in the structural modification and functionalization of chitin-based materials aimed at improving their antimicrobial performance. The mechanisms underlying the antimicrobial action, structure–activity relationships, and synergistic interactions with incorporated agents are critically examined. Furthermore, the review explores the diverse applications of these enhanced materials in fields such as food packaging, wound healing, water treatment, and biomedical devices. By summarizing the current progress and identifying ongoing challenges, this work aims to guide future research directions in the design of effective chitin-based antimicrobial systems.

This study investigates electrospun polyvinyl chloride/thermoplastic polyurethane (PVC/TPU) nanocomposite membranes embedded with 0, 0.05, 0.10, and 0.15 wt% functionalized multi-walled carbon nanotubes (fMWCNTs). The fMWCNTs were thermally treated and functionalized to improve dispersion and interfacial adhesion. SEM analysis revealed uniform nanofibers with diameters of 70–85 nm and no bead defects. FTIR confirmed the presence of hydrophilic functional groups on fMWCNTs. Mechanical tests showed a substantial increase in elastic modulus from 30 MPa (pristine membrane) to 334 MPa with 0.15 wt% fMWCNTs. Water contact angle decreased from 127° to 68°, indicating enhanced hydrophilicity and improved wettability of the electrospun membranes incorporated with fMWCNTs. Permeation experiments using humic acid (HA) as a model pollutant demonstrated high water flux: 551 L.m^− 2.h^− 1 for pure water and 388 L.m^− 2.h^− 1 for HA solution with the 0.15 wt% fMWCNT membrane. This membrane also achieved over 99% HA rejection and a low irreversible fouling ratio (6.7%) after 240 min, highlighting excellent antifouling performance. The incorporation of fMWCNTs significantly enhances mechanical strength, hydrophilicity, permeability, fouling resistance, and performance stability of the membranes. These results indicate that PVC/TPU/fMWCNT nanofiber membranes are highly promising for efficient removal of organic pollutants in wastewater treatment applications.