Journal of Applied Polymer Science最新文献

Membranes are applied across numerous fields, including the separation of pharmaceutical waste, due to their affordability, high efficiency in contaminant removal, and versatile functionality. Nevertheless, the efficiency of membranes is substantially compromised by fouling. Incorporating hydrophilic inorganic components has proven effective in mitigating membrane fouling. This study focuses on developing novel mixed-matrix membranes for separating and recovering ascorbic acid (vitamin C) from aqueous solutions using manganese nanoparticles (MnO₂, Mn₂O₃) in polysulfone (PSF) casting solutions. The membranes underwent analysis via thermogravimetric analysis, microscopic and spectroscopic techniques, and evaluations of their mechanical properties, contact angle, and internal membrane-specific area. Characterization of the synthesized nanoparticles included X-ray diffraction and transmission electron microscopy. UV spectrophotometry at 260 nm was used to measure ascorbic acid concentrations in feed and fitrate solutions. Incorporating Mn₂O₃ Nanoparticles in flat sheet nanofiltration membranes and a pilot-scale nanofiltration unit demonstrated enhanced permeate flux and effective pharmaceutical rejection. The resulting membranes are applicable across various industrial sectors. When MnO₂ NPs were embedded in the polysulfone matrix, mechanical testing exhibited an increase in tensile strength. MnO₂, NP-blended PSF casting solutions exhibited enhanced surface hydrophilicity as proved by contact angle measurements. Fouling tests highlighted the $�\; ��\; �\mathrm{PSF}�\; �/��$Mn₂O₃ Membrane's superior antifouling properties indicate that nanoparticle addition enhances membrane porosity, hydrophilicity, water flux, and antifouling characteristics.

In this paper, air plasma is used to modify polypropylene (PP) to improve the compatibility of PP and poly olefin elastomer (POE), and then improve the electrical and mechanical properties of PP/POE cable insulation materials. Firstly, PP insulation material was modified by air plasma, and PP/POE blends of different proportions were prepared. Secondly, the physicochemical properties of PP/POE blends before and after modification were characterized, and their electrical and mechanical properties were tested. Finally, the mechanism of enhancing the compatibility between PP and POE by air plasma and the effect of compatibility on the electrical–mechanical properties of PP/POE blends were analyzed. The experimental results show that after the modification of PP by plasma treatment, the compatibility between the modified PP and POE is significantly improved, and the electrical and mechanical properties of the modified PP/POE (m-PP/POE) blend are enhanced. Furthermore, the higher the content of POE in the blend sample, the more significant the improvement in the electrical and mechanical properties of the m-PP/POE blend. When the ratio of PP to POE component is 6:4, the power frequency dielectric loss of modified PP/POE (m-PP/POE) sample is reduced by about 31.5% (from 9.10 × 10⁻⁴ to 6.23 × 10⁻⁴), the volume resistivity is increased by about 2 times (from 3.57 × 10¹⁵ to 6.14 × 10¹⁵ Ω cm), the breakdown field strength is increased by 14.2% (from 63.5 to 72.5 kV/mm), and the elongation at break is increased by 15% (from 1164.88% to 1339.61%). This work provides a new idea for improving the compatibility of PP and POE, and has great reference significance for improving the performance of high-voltage polypropylene cables under dual-carbon background.

Conductive hydrogels have great potential as flexible sensors in wearable devices. However, it remains a challenge to integrate excellent mechanical properties, high conductivity, and sensitivity into hydrogels using simple green methods. Here, cellulose nanofibers (CNFs) and MXene were introduced into a polyvinyl alcohol (PVA) hydrogel system based on the multi-scale synergistic enhancement mechanism of nanocomposites. By forming interfacial hydrogen bonds and entanglement of molecular chains, a nanofiber-reinforced PVA/CNF/MXene (PCM) hydrogel was developed. MXene enhances the electrical conductivity of the hydrogel, reaching 0.175 S/m, which represents a 191.7% increase compared to the hydrogel without MXene. The synergistic enhancement between CNF and MXene confers the PCM hydrogel with high mechanical strength (334 kPa) and high stretchability (339%). Moreover, PCM hydrogel serves as a strain sensor with outstanding strain sensitivity (GF = 3.25), wide dynamic detection range (0%–220%), and low detection threshold (0.3%), demonstrating excellent stability and durability in response to stimulus signals. The hydrogel sensor enables accurate detection of subtle human movements and synchronized control of robotic arms, demonstrating its broad applicability in motion monitoring and human–machine interaction (HMI).

Visbreaking is a widely employed strategy to fine-tune the molecular weight distribution (MWD) of polypropylene (PP), yet direct comparisons of polydispersity index (PDI) across analytical techniques remain limited. In this study, polypropylene homopolymer (H-PP) powder was visbroken using varying concentrations of an organic peroxide (0 to 800 ppm), aiming to achieve high melt flow rate (MFR) grades while optimizing peroxide consumption. Molecular weight averages and polydispersity index were evaluated using triple detection size exclusion chromatography (SEC) equipped with infrared (IR5), online viscometer, and multi-angle light scattering (MALS) detectors. Rheological crossover modulus measurements were used to estimate PDI independently. The SEC studies confirmed systematic chain scission with increasing peroxide concentration, reflected in declining M_n and M_w values. Notably, PDI trends from MALS closely aligned with rheological estimates across all peroxide levels, while IR5 and viscometer-based values showed significant deviations. These findings demonstrate that MALS is a reliable SEC detector for detecting molecular weight distribution changes relevant to melt relaxation and processability. The study provides a framework linking chromatographic characterization with rheological behavior in polypropylene, offering a practical analytical pathway for industrial polyolefin evaluation.

This work reports, for the first time, the fabrication of poly(vinyl alcohol)–methylcellulose (PVA–MC)/BaTiO₃-SiO₂ nanocomposite films via a simple casting method. This innovative approach enables the synergistic integration of the flexibility and film-forming ability of PVA–MC with the high dielectric and optical properties of BaTiO₃-SiO₂ nanoparticles. As a result, the hybrid films exhibit enhanced structural integrity and superior optical performance compared to conventional nanocomposite membranes. The microstructural, morphological, and optical characteristics of the PVA–MC/BaTiO₃SiO₂ films were systematically investigated. Results show that absorbance increased by 88.7% in the UV region (λ = 320 nm) and by 92% in the near-infrared region (λ = 760 nm) at a BaTiO₃SiO₂ content of 6.7 wt%. Moreover, the allowed indirect band gap decreased from 4.1 to 1.6 eV with increasing nanoparticle loading, confirming the improved optical performance. These findings highlight the novelty and potential of PVA–MC/BaTiO₃SiO₂ hybrid films as cost-effective, high-performance nanomaterials for nano-optical and optoelectronic applications. The (PVA–MC)/BaTiO₃SiO₂ nanocomposite films were tested for gamma radiation shielding application. The results showed these nanocomposite films included high attenuation coefficients, good flexibility, and low cost.

The growing demand for multifunctional sensors in wearable systems has prompted the need for materials that simultaneously support gas sensing and mechanical strain detection. However, current flexible sensing materials still suffer from issues such as response hysteresis, poor humidity resistance, and lack of antibacterial properties. Herein, we developed a ternary flexible composite by integrating defect-engineered ZIF-8, conductive polypyrrole (PPY), and bacterial cellulose (BC), which was further encapsulated with polydimethylsiloxane (PDMS) to form the Def-ZIF-8/PPY/BC@PDMS composite. The results demonstrated that with 2–3 layers of PDMS, the sensor achieved a fast and stable NO₂ response (9.3% at 10 ppm), with reliable recovery. Under 80% relative humidity, PDMS reduced humidity-induced signals from 34% to 10.3%, confirming markedly improved moisture resistance. The incorporation of a PDMS layer enabled enhanced stress sensing, reducing the response/recovery times to 0.4/0.3 s from 0.9/0.8 s in the uncoated structure. The sensor demonstrated high fidelity in recognizing complex biomechanical signals such as swallowing, walking, and finger articulation. Furthermore, antibacterial testing confirmed 42.18% and 64.69% inhibition against Escherichia coli and Staphylococcus aureus, respectively. This multifunctional composite simultaneously optimizes gas sensing, mechanical flexibility, humidity resistance, and antibacterial efficacy, paving the way for advanced materials in fully integrated wearable sensing technologies.

Acrylonitrile-butadiene-styrene (ABS) resin faces significant fire hazards due to inherent flammability, necessitating halogen-free flame retardants with minimal mechanical compromise. Herein, novel cerium diethylenetriamine penta(methylene phosphonate) (CeDETPMP) complexes were molecularly engineered via hydrothermal synthesis, systematically tuning Ce³⁺-to-ligand ratios (from 1:3 to 3:1) to optimize coordination geometry. At 1 wt% loading, CeDETPMP synergized with an intumescent flame retardant (IFR, 19 wt% ADP/PAPP) to enable ABS composites to achieve UL-94 V-0 rating and a limiting oxygen index (LOI) of 24.8%, while reducing peak heat release rate (PHRR) by 73.8% and total smoke release (TSR) by 35.4% in cone calorimetry. Crucially, Ce³⁺/Ce⁴⁺ redox cycling catalyzed graphitized char formation, suppressing crack propagation and enhancing barrier integrity. The optimal CeDETPMP (1:3) and CeDETPMP (3:1) ratios minimized mechanical sacrifice compared to ABS/IFR systems, retaining tensile strength within 26 MPa and 11 kJ/m². This work establishes a structure–property paradigm for rare-earth synergists in high-safety polymer engineering.

Manganese ferrite (MnFe₂O₄, MnF) nanoparticles were synthesized via a co-precipitation route and subsequently surface-functionalized with polyethylene glycol (PEG) through a mass titration method. Structural and morphological analyses (SEM, XRD, EDX, FTIR) confirmed a monophasic cubic spinel structure with an average crystallite size of 23 nm and a slight grain growth after PEG modification. DM simulation revealed the homogeneous grafting of PEG without interfering with the parent spinel structure of MnF. Magnetic measurements (VSM, ZFC) revealed superparamagnetic behavior for pristine MnF (M_s = 37.25 emu g⁻¹) and a transition to weak ferromagnetism for PEG@MnF (M _s = 22.7 emu g⁻¹), attributed to surface modification. Dielectric studies further highlighted the multifunctional nature of the material. Photocatalytic performance was evaluated via the degradation of thiamethoxam, a widely used pesticide. Under optimal conditions (80 min, 10 ppm, 0.04 g catalyst, 65°C), PEG@MnF exhibited significantly enhanced degradation efficiency compared to unmodified MnF, owing to improved dispersibility, reduced agglomeration, and a higher density of active sites imparted by PEG. Degradation intermediates were identified using GC–MS and FTIR, and a plausible degradation pathway was proposed. These results demonstrate that PEG functionalization markedly improves the magnetic, dielectric, and photocatalytic performance of MnF, establishing PEG@MnF as a promising catalyst for sustainable environmental remediation.