Journal of Polymer Science最新文献

Solar-driven interfacial water evaporation technology is recognized as a highly effective method for water purification. By incorporating photocatalytic degradation capabilities, it can further enhance the efficacy of wastewater treatment involving dye pollutants. In this study, poly(arylene ether nitrile) (PEN), a high-performance engineering plastic, was fabricated into a robust nanofibrous membrane substrate through electrospinning technology. The membrane was functionalized with polyaniline (PANI) through in-situ polymerization and subsequently doped with TiO₂. As a result, dual-functional PANI/TiO₂/PEN composite membranes were obtained, exhibiting properties suitable for solar-driven interfacial water evaporation and photocatalytic dye degradation. In this study, by modulating the surface morphology of PANI particles through involving in-situ growth on the PEN membrane using different surfactant pretreatments and varying HCl concentrations, a high evaporation rate of 3.17 kg m⁻² h⁻¹ was ultimately achieved. However, the dye removal rate reached 95.98% for methylene blue (MB) dye pollutant, owing to the adhesion of TiO₂ with photodegradation ability and the porous electrospun membrane with absorption properties. This study demonstrated high-efficiency water evaporation by modulating PANI morphology and offers a valuable strategy for constructing dual-functional nanofibrous membranes with both water evaporation and dye degradation capabilities for wastewater treatment applications.

In this work, in order to achieve the halogen-free magnetic superhydrophobic flame-retardant PU-based sponge for oil–water separation, the pure PU sponge was first coated with the flame-retardant alternate cationic poly(ethylene imine) (PEI) and anionic phytic acid (PA) layers using a self-assembly method, and then was further covered by the hydrophobic hexadecyltrimethoxysilane (HDTMS)-modified magnetic Fe₃O₄ nanoparticles using the hydrophobic Sylgard 184 siloxane adhesive to form a series of H-Fe₃O₄/PU sponges. The structure of the resulting H-Fe₃O₄/PU sponges was studied by scanning electron microscope, energy-dispersive x-ray mapping, Fourier transform infrared spectroscope, wide-angle x-ray diffraction, x-ray photoelectron spectroscope, Raman spectroscope, and thermogravimetry analysis, confirming the existence of PEI, PA, HDTMS, Fe₃O₄ nanoparticles, and Sylgard 184 siloxane adhesive on the PU sponge surface. The H-Fe₃O₄/PU sponge obtained through seven layers of self-assembly not only was superhydrophobic with the water contact angle of 153^o and magnetic with the magnetization strength of 7.9 emu/g at 50,000 Oe but also has the flame-retardancy characteristic. In addition, it was found that the oil–water separation could be realized by direct adsorption and gravity filtration using the H-Fe₃O₄/PU sponge, and the reusing of the H-Fe₃O₄/PU sponge for oil adsorption was stable due to its good mechanical property.

Epoxidized natural rubber (ENR), produced via the epoxidation of natural rubber (NR), has important economic value. The introduced epoxy groups significantly enhance the polarity and reactivity of the polymer matrix, granting ENR considerable potential for applications. This study chooses octadecyl trimethyl ammonium chloride (OTAC) as the surfactant in NR latex to produce ENR by in-situ method. ENR with different epoxidation degrees (EPD) can be rapidly synthesized at higher dry rubber content (DRC) and temperature in OTAC-stabilized latex than nonylphenol ethoxylate (OP-10) stabilized latex. The effects of DRC of latex and temperature on the epoxidation reaction are systematically investigated. The results reveal that the OTAC-stabilized system enables efficient epoxidation at a high DRC (50%), while exhibiting minimal ring-opening of epoxy groups. The viscosity and Zeta potential analysis reveal the contributions to the excellent colloid stability of OTAC modified latex and superior long-term storage stability. Dilution experiments of the ENR latex validate the exceptional stability of the OTAC-stabilized system. Structural analysis of surfactants during the epoxidation process indicates OP-10 underwent oxidative degradation, whereas OTAC maintained structural integrity. This study provides an efficient strategy for the stable production of ENR and ENR latex with different EPD, especially those with EPD higher than 50%.

We developed diselenide-crosslinked polymeric nanoparticles using a ROMP-synthesized amphiphilic block copolymer, PNEG-b-(Nor-SeH). The selenol group was introduced via nucleophilic substitution of sodium diselenide with PNEG-b-(Nor-Cl), followed by self-assembly into PNPs via oxidative crosslinking, forming an ROS-sensitive linker. ¹H NMR study confirmed the successful synthesis of monomer and polymer (PNEG-b-(Nor-Cl)). GPC analysis confirmed the successful synthesis of block copolymer (Mn = 79.9 kDa). EDS analysis of DC PNPs showed a selenium content of ~8.02 wt%, confirming successful Se incorporation. The DLS analysis revealed that blank DC PNPs are at 190 ± 5.3 nm and enlarge slightly to 207 ± 8.9 nm after DOX loading, which is suitable for EPR-mediated tumor accumulation. The diselenide shell endowed PNPs with strong colloidal stability, holding their size essentially constant for 72 h of studies in normal conditions with the least DOX release rate (~10%). In contrast, ROS challenge triggered rapid liberation of drug: at 10 μM H₂O₂ (52%) was released and ~93% at 50 μM H₂O₂ within the same window of 72 h, confirming efficient, tumor-relevant responsiveness. MTT assay showed cytotoxic effects on HeLa cells, with viability decreasing to 35% at higher DOX@DC PNPs concentrations, while normal cells maintained 92% viability. Cellular uptake analysis showed doubled intracellular fluorescence after 12 h.

Neuropsychiatric diseases affect a large part of the world population and, in addition to impacting mental health, compromise the emotional, cognitive, and social well-being of relatives and friends, in addition to representing a significant financial burden for health systems. Current pharmacological treatments often require high dosages to achieve therapeutic efficacy, leading to a range of adverse effects. In this study, we report on the development and characterization of a biopolymeric nanocarrier based on poly(Ɛ-caprolactone) for the smart delivery of lithium (Li), focusing on the treatment of neuropsychiatric disorders. The nanocarrier was characterized using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), thermogravimetric analysis (TG/dTG), differential scanning calorimetry (DSC), Zeta potential, and dynamic light scattering (DLS). As a result, the nanocarrier presented a spherical morphology and achieved a Li loading efficiency of (83% ± 1%). The Li release kinetics followed a pseudo-first-order controlled model (R ² = 0.9769), highlighting the system's capability for sustained and smart drug release. Biomimetic biological barrier penetration studies confirmed the nanocarrier's ability to transport and release Li effectively. A cell viability assay using VERO cells indicated high biocompatibility and low cytotoxicity. Additionally, fluorescence analysis of albumin revealed significant interaction, suggesting potential transport via the circulatory system.

The high dielectric constant inherent to traditional polyimides (PIs) limits their ability to meet the demands of high-frequency circuit boards. The challenge of reducing this dielectric constant, while simultaneously preserving or enhancing the material's overall performance, is of critical theoretical and practical significance for advancing the use of PIs in the 5G communication sector. In this study, fluorinated graphene/polyimide (FG/PI) was employed as a reinforcing layer to fabricate a double-layer structure that enhances the mechanical and breakdown properties of low-dielectric PIs. PI porous composite films were developed using a layer-by-layer coating method, and their dielectric, mechanical, and thermal properties were investigated. The resulting double-layer PI films exhibited low dielectric constants and robust comprehensive performance. Specifically, the dielectric constants of the three films, PI-1, PI-2, and PI-3, were 2.01, 1.90, and 1.70, respectively, with corresponding tensile strengths of 42.69 MPa, 37.54 MPa, and 24.41 MPa, and breakdown strengths of 180.75 kV mm⁻¹, 138.70 kV mm⁻¹, and 89.77 kV mm⁻¹. These results underscore the importance of multi-layer structural designs in enhancing the breakdown resistance and mechanical properties of porous films, which are critical for the practical application of low-dielectric porous PI materials.

Nanofibers are considered suitable candidates for drug delivery applications due to their high surface-to-volume ratio, which solves the issue of sustained drug delivery suffered by other biocomposite morphologies. However, the complexity is increasing due to the increasing expectations from the drug delivery systems (DDSs), and a more complex system for crucial challenges is needed. Mathematical modeling is essential for drug-related applications since it gives insight into the release mechanism and can help redesign the system. However, the current literature lacks the study of release kinetics from whole biopolymeric nanofibrous DDSs, and the studies mostly involve some inorganic moiety in the DDS, which can potentially be toxic. In addition, literature also lacks the effect of the presence of a drug carrier and the method of drug loading on the release kinetics. The current work uses NES to fabricate polylactic acid (PLA)/chitosan (CS) (10:0.1 w/v%) and polylactic acid/chitosan/nanocrystalline cellulose (NCC) (10:0.1:0.05 w/v%) based nanofibers and studies the effect of the presence of NCC and drug loading method on release kinetics using various models. The DDS with the pre-loaded drug on the nanocarrier NCC showed the best sustained release confirmed by mathematical modeling, while PLA/CS DDS failed to show sustained release and followed the saturation kinetics model. The current study provides insight into the complex biopolymeric nanofibrous system and highlights the importance of the neglected parameter of drug loading on release kinetics.