Journal of Applied Polymer Science最新文献

The transport properties of binary electrolyte components in ethylene propylene diene monomer (EPDM) and hydrogenated nitrile rubber (HNBR) vulcanizates were systematically investigated using the equilibrium swelling method. The results demonstrated that the transport behavior of binary electrolyte components in EPDM and HNBR matrices was not only dependent on compatibility but also significantly affected by temperature. Enhanced transport behaviors were observed when higher similarity in polarity existed between components and at elevated temperatures. The permeability activation energy of the binary electrolyte components in EPDM increased by approximately 27.2%, while that in HNBR increased by 65.9%, when the EC content in the EC/DEC binary electrolyte components was increased from 25% to 75%. Furthermore, the Flory–Huggins interaction parameter (χ) was calculated and correlated with P using three-dimensional solubility parameters, and it was observed that the fitting curves of HNBR vulcanizate were positioned above those of EPDM vulcanizate, with both systems exhibiting inverse proportional function relationships when EC was present in the binary electrolyte components; otherwise, linear relationships were established. This study provided a key theoretical basis for the design of lithium battery sealing materials.

Polyacrylic acid has a wide range of applications in the field of superhydrophilicity, but due to its single composition, there are problems such as insufficient mechanical strength and functional limitations. In order to extend its application, we prepared a new IPN hydrogel PEI-PAA/PDMC. The results show that the new hydrogel loaded on different substrates (stainless steel mesh/filter cloth) possesses superhydrophilicity (WCA < 10°) and underwater superoleophobicity (OCA > 150°). The hydrogels not only separated oil–water mixtures with high throughput and efficiency (98%, 12,000 L m⁻² h⁻¹), but also separated oil-in-water emulsions by gravity alone (95%, 700 L m⁻² h⁻¹). Due to the large number of quaternary ammonium groups in the DMC, we have tested the antimicrobial properties of the DMC with excellent results (99.2% inhibition). Compared with previous studies, this paper introduces that PEI has the ability to adsorb heavy metals, and we tested Cu²⁺ and found that the adsorption and separation efficiency reached 75%. This study provides new ideas for the direction of wastewater treatment.

Epoxy resins, although valued for their superior mechanical strength and chemical resistance, inherently suffer from brittleness that limits their application in impact-critical domains. Conventional toughening approaches often compromise thermo-mechanical properties or require complex processing. In this study, we developed a novel intrinsic toughening strategy by synthesizing a highly toughened epoxy resin (HDI-T EP) through molecular design, utilizing hexamethylene diisocyanate trimer as the core structural unit. Through block, ring-opening, and ring-closing reactions, flexible aliphatic chains were incorporated into the resin's molecular architecture. The optimized HDI-T EP(15) exhibits remarkable overall enhancements over EP Neat: a 26.7% increase in tensile strength, a 61.9% greater elongation at break, a 29.7% higher compressive strength, and a 114.8% improvement in impact strength. Critically, this substantial improvement in mechanical properties occurred without compromising essential characteristics. The modified resin maintained comparable thermal stability, including a suitable glass transition temperature, alongside excellent chemical resistance in corrosive environments. The synergistic modification strategy in this work overcomes the epoxy's brittleness-toughness trade-off. By integrating flexible chains for energy dissipation and a trifunctional core to raise cross-linking density, it enhances toughness without sacrificing strength or thermal stability, thereby broadening practical applications.

Polyvinyl alcohol (PVA) has superb chemical and physical characteristics, making it important for applications in many areas, but its combustibility limits its broader use. In this work, ZIF-67@BN, a flame-retardant and heat-conducting filler, was synthesized via the in situ growth technique, and its structural and morphological characteristics were studied. ZIF-67@BN and ammonium polyphosphate (APP) were added to PVA. The findings verify that the LOI value of PVA composites with 1 wt.% of ZIF-67@BN and 7 wt.% of APP attained 28.1%, which was 36.4% greater than that of pure PVA. In addition, the total heat rate (THR) was 39.0% lower than that of pure PVA, and the peak heat release rate (pHRR) was 61.6% lower. This is because ZIF-67@BN has a physical barrier effect as a filler and catalyzes the carbonization effect. When heated, APP's decomposition generated non-flammable gas dilution; at the same time, the production of phosphoric acid and metaphosphoric acid contributed to the dehydration during the carbonization of PVA.

Vanadium nitride has garnered extensive attention due to its high specific capacitance and wide electrochemical window (−1.2 to 0 V). Nevertheless, the preparation techniques of vanadium nitride, as well as its dissolution and surface oxidation, have restricted its extensive application. This work proposes a novel approach of interpenetrating polymer network polyvinyl alcohol/polyacrylamide (PVA/PAM) induction to prepare vanadium nitride nanoparticles embedded in a N-doped porous carbon composite (VN/NPC) in an inert atmosphere. The fabricated VN/NPC material shows a specific capacitance of 248.3 F g⁻¹ at 0.5 A g⁻¹ with an excellent cycle life of 96.2% after 10,000 cycles. Further, the assembled Ni(OH)₂//VN/NPC asymmetric supercapacitor device can achieve a high energy density of 32 Wh kg⁻¹ with a good capacitance retention of 91.7% after 10,000 cycles.

This study investigates polyvinyl chloride (PVC) slow pyrolysis in a tubular furnace, focusing on hydrogen chloride (HCl) removal efficiency via calcium oxide (CaO) addition. Key parameters include temperature (500°C–550°C) and Ca/Cl molar ratios (optimized at 2:1). Solid residues from co-pyrolysis were characterized by scanning electron microscopy (SEM)/energy-dispersive x-ray spectroscopy (EDS) and x-ray diffractometry (XRD) for morphology and crystallinity. Liquid products were analyzed via Fourier-transform infrared spectroscopy (FTIR), while gas compositions were determined using gas chromatography (GC). Results show that a 2:1 Ca/Cl ratio provides maximum reactive sites for HCl neutralization. Alkaline calcium chloride concentration peaked at 500°C, indicating optimal HCl removal efficiency at this temperature. Notably, HCl removal reached 93.4% at 550°C with a 2:1 Ca/Cl ratio. Tar and gas byproducts were characterized, though detailed compositional analysis was not emphasized. The findings establish a theoretical framework for HCl mitigation during PVC thermal recycling, highlighting CaO's role in neutralizing acidic chlorides. Temperature and CaO dosage directly influence removal efficiency, offering practical insights for industrial-scale waste PVC processing. This work advances sustainable PVC recycling strategies by optimizing reaction conditions for reduced environmental and health risks.

Series water washable and UV-curable polyurethane acrylate (PUA) resins were prepared using isophorone diisocyanate (IPDI) and polyhydric alcohols as structural units. The structures of PUA resins with different types of polyols, different R values (NCO/OH ratios), and molecular weights were well characterized. Physical properties, water contact angle, and washability of PUA resins were examined. Mechanical properties, thermal stability, and curing shrinkage properties of PUA resins after photopolymerization were also investigated. The optimized formulation (IPDI-PPG-1000-2.5) (PPG: polypropylene glycol) exhibited its superior properties such as mechanical properties, thermal stability, water washable properties, and curing shrinkage rate with a Young's modulus of 325.20 MPa, a tensile strength of 7.25 MPa, and a temperature of 224.5°C at a mass loss of 5%, respectively. This PUA resin is capable of producing 3D physical entities via photopolymerization with smooth surfaces and clearly defined shapes. Also, no sticky touch on the surface was obtained after washing with water. This work provides an innovative strategy to prepare high-performance water washable PUA resin that could be applied in 3D printing.

In this study, a novel diamine 4-(2,6-bis(4-(trifluoromethyl)phenyl)pyridine)phenyl-3,5-diaminobenzoate (FPPAB) containing trifluoromethyl, pyridine, and ester groups was synthesized by a three-step organic reaction. Then, four structures of copolyimides were prepared by a one-step polycondensation reaction using diamine (FPPAB), dianhydride 4,4′-(hexafluoroisopropyl)diphthalic anhydride (6FDA), and four commercial diamines. The synthesized copolyimides exhibited high thermal stability, with the glass transition temperature (T _g) and 5% loss temperature (T _5%) in the range of 210°C–256°C and 343°C–452°C, respectively, and X-ray diffraction analysis indicated that the copolyimides featured a d-spacing of 4.90–5.57 Å. They also showed excellent solubility in both high and low boiling point organic solvents. Furthermore, the membranes not only had outstanding optical properties (wavelength range of 80% transmittance = 378–454 nm) but also had excellent hydrophobicity (water contact angle > 91.96°). Notably, the copolyimide membrane with a fluorene structure showed the highest gas permeability (P(He) = 46.27, P(CO₂) = 21.06, P(N₂) = 1.57 barrer) and favorable selectivity (α(He/N₂) = 29.55, α(CO₂/N₂) = 13.69). This membrane also exhibited the largest fractional free volume (FFV). Overall, the prepared copolyimides exhibited a well-balanced combination of properties, particularly in gas separation performance, indicating that the properties of copolyimides could be effectively optimized by adjusting the structure of monomers.

The development of eco-friendly, high-efficiency surfactants is critical for advancing sustainable waterborne coatings. In this study, a novel Gemini surfactant (TA-TD) was synthesized via solvent-free esterification between tung oil acids (TA) and 2, 5, 8, 11-Tetramethyl-6-Dodecyne-5, 8-Diol Polyoxymethylene Ether (TDDPE). Structural analysis (FTIR, ¹H NMR, GPC, GC–MS) confirmed complete reaction and successful molecular integration at an optimal TA:TDDPE ratio of 2:1. Compared with a commercial wetting agent (CAB-35, FMES, Tween-80 and 1227), TA-TD-2.0 demonstrated superior performance, including lower critical micelle concentration (CMC), faster dynamic surface tension reduction, and significantly reduced contact angle on hydrophobic substrates. Furthermore, TA-TD-2.0 improved coating gloss, water resistance, and salt spray durability, while maintaining excellent defoaming properties and low VOC compatibility. These advantages stem from its unique Gemini structure and long-chain hydrophobicity derived from renewable tung oil. The combination of high efficiency, multifunctionality, and sustainable sourcing highlights the commercial potential of TA-TD as a next-generation green surfactant for environmentally responsible coating systems.