Polymer International最新文献

Biopolymers have gained prominence due to their potential in tissue engineering, which includes hydrophilicity, lower toxicity, reduced immune rejection, biocompatibility and biodegradability. However, biopolymers typically exhibit low mechanical strength, which decreases their application potential in tissue engineering. Composites of natural and synthetic polymers offer a robust solution to overcome this challenge, as the stiffness and durability of composites are enhanced by the presence of synthetic polymers. This study investigates two composite sandwich model scaffolds for skin tissue engineering, focusing on their structural and regenerative properties. The composite scaffolds were fabricated by combining freeze-drying and 3D-printing techniques. The outer layers of the scaffolds were fabricated using collagen–carrageenan (CO/CA-PCL) or collagen–carrageenan–chitosan (CO/CA/CH-PCL) through freeze drying, whereas the core layer was formed by 3D-printed polycaprolactone (PCL) mesh. Crosslinking was achieved in the vapor phase of glutaraldehyde and scaffold groups preserved their structure through 28 days after an initial weight loss on day 1. The CO/CA/CH-PCL scaffold showed a lower degradation rate with a cumulative weight loss of 28.6 ± 5.5% compared to the CO/CA-PCL scaffold which indicates improved stability of the three-polymer sponge. Both scaffolds achieved water retention above 800% after 14 days of incubation which is critical for wound healing. Tensile strength of both scaffolds was successfully supported by 3D-printed PCL mesh. In vitro study has shown that the chitosan-bearing CO/CA/CH-PCL scaffold is promising for use in skin tissue engineering by supporting L929 attachment and high L929 cell viability. © 2025 Society of Chemical Industry.

This study explores the development of lightweight thermal insulators based on ethylene propylene diene monomer (EPDM) reinforced with silica aerogel. Silica aerogel was synthesized via a sol–gel process and characterized using Brunauer–Emmett–Teller and scanning electron microscopy analyses, revealing its highly porous structure and low-density properties, making it an ideal reinforcement material. The EPDM composites were formulated with different silica aerogel concentrations (10–30 phr) and evaluated for their mechanical, thermal and ablative properties using Tensile, thermogravimetric analysis/differential scanning calorimetry and an oxyacetylene flame, respectively. The incorporation of silica aerogel significantly enhanced the mechanical performance of the composites. The thermal conductivity of the composites was reduced significantly, demonstrating superior insulation properties over fumed silica-filled EPDM. Thermogravimetric analysis indicated improved thermal stability, with a maximum degradation temperature of 474 °C for the 30 phr silica aerogel-filled composite. Additionally, ablation tests confirmed that the char layer tenacity of the silica aerogel/EPDM composites was enhanced, and demonstrated superior resistance to high-temperature environments, improved by the inclusion of Kevlar pulp, and achieved a linear ablation rate below 0.2 mm s⁻¹. These findings position silica aerogel as a promising reinforcement for EPDM-based thermal insulators, striking a balance between low weight, enhanced mechanical strength and excellent thermal insulation. © 2025 Society of Chemical Industry.

An amphiphilic block copolymer, poly(ethylene glycol)-b-poly(N-vinyl carbazole), functionalized with a 1,8-naphthalimide fluorescent signaling moiety containing a pH-responsive piperazinyl recognition unit (PEG-b-PVK-co-PNA), was synthesized via reversible addition-fragmentation chain transfer polymerization. The block copolymer demonstrates a low molar mass dispersity and spontaneously self-assembles into uniform nanoparticles in aqueous media, serving as a fluorescent sensor for detecting hydrogen ion. The emission from the PVK block is effectively quenched, whereas the 1,8-naphthalimide moiety exhibits a pronounced fluorescence enhancement at 505 nm due to Förster resonance energy transfer between the PVK donor and the 1,8-naphthalimide acceptor in the copolymer nanoparticles. The photoluminescence intensity at 505 nm displays a linear correlation with decreasing pH values in the range 3.0–6.5 for the copolymer nanoparticles in acidic medium, highlighting the block copolymer's potential for quantitative pH sensing in acidic environments. © 2025 Society of Chemical Industry.

Geotextiles are typically used to stabilize steep earthen structures to prevent landslides. Usually, such geotextiles are made from petrol-based polymers (such as polypropylene), but the use of biodegradable geotextiles seems to have specific benefits. Therefore, the present work investigates the mechanical and physicochemical properties of special polymer blends, made from polylactic acid, polybutylene adipate terephthalate and starch. These polymers are receiving increasing attention from industry due to their biodegradability properties and their possibility of economic production. The polymers were mixed with a laboratory extruder and the received homogeneity of the blends was characterized by SEM investigations. The ratio of the different polymers in these blends was varied to understand the relationship between the composition of the blends and the important properties for use in geotextiles. The size of the embedded particles was investigated with SEM and its relation to different mechanical properties was analyzed. The mechanical and viscoelastic properties of the prepared blends were analyzed with quasi-static tensile testing, dynamic mechanical analysis and rheology measurements. In addition, the advanced nanoIR-AFM technique was used to characterize the different prepared polymer blends. © 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

In this work, a high performance thermoset material was made from the natural product honokiol which is a diphenolic lignan derived from magnolia bark extract (Magnolia officinalis). Honokiol was cyanated to form the corresponding honokiol dicyanate ester (HONOCY), which was thermally cured forming honokiol polycyanurate (HONOPC) thermoset which was fully characterized. The cyanate ester resin showed excellent low temperature viscosity (0.2 Pa s at 55 °C), while the cured polycyanurate had char yields of 75% and 64% up to 600 °C in nitrogen and air atmospheres, respectively. The polycyanurate had a high decomposition temperature of 449 °C along with a glass transition temperature greater than 400 °C. HONOCY then represents a significant improvement for low temperature processing of high performance bio-based cyanate ester polymers for high temperature applications. © 2025 Society of Chemical Industry.

With the increasing demand for portable electronic devices, it is urgent to develop a flexible energy storage system with high performance and good stability. In this paper, a new kind of poly(vinyl alcohol)–polypyrrole–acidified carbon nanotube (PVA–PPy–CNT-COOH) conductive composite hydrogel was prepared using a freezing–thawing method for fabricating flexible symmetric solid-state supercapacitors. The PVA–PPy–CNT-COOH conductive composite hydrogel has a unique three-dimensional interpenetrating network structure and functional components, endowing the prepared hydrogel with softness, elasticity, compressibility and formability. Furthermore, the influence of feed mode and feeding ratio on hydrogel preparation was explored. According to the optimal experimental process, a flexible symmetric solid-state supercapacitor with high energy storage capacity and stability was fabricated using PVA–PPy–CNT-COOH as the electrode. The capacitance change of the supercapacitor was almost negligible when subjected to 50% strain. Even at 70% strain, the retention rate of volume specific capacitance was still about 88%. This study not only provides a preparation method for a new electrode material but also develops a new type of high-performance and stable flexible symmetric solid-state supercapacitor, which has potential application prospects in flexible energy devices. © 2025 Society of Chemical Industry.

Acquiring freshwater from seawater, the solar interfacial vapor generator (SIVG) offers a passive and decentralized approach to addressing water shortage problems. However, the performance of current SIVGs is greatly restricted by the disadvantages of poor controllability and manipulation of seawater transport porous structure and the evaporation interface. To realize rapid seawater replenishment and highly efficient vaporization, we developed a novel polyethylene terephthalate (PET) SIVG with small-sized oriented pores and an ultrathin photothermal conversion layer that exhibited a highly efficient water evaporation rate under both simulated solar and outdoor sunlight illumination. The well-arranged and highly oriented pores with controllable size in PET acted as a confined mass transfer fluid pump to spontaneously transport seawater to the evaporation layer, in which a maximum height of 68 mm via the capillary rise mechanism was reached. The resultant PET layer possessed a low density of 0.08 g cm⁻³ that exhibited an ideal floating performance to steady the interfacial evaporation. Moreover, due to the superior dispersion structure in the photothermal conversion layer, the surface temperature of the SIVG greatly increased to 101.2 °C within 45 s, and the evaporation rate reached 1.26 kg m⁻² h⁻¹. This work provides a novel strategy for preparing a high performance SIVG and also paves an innovative way for obtaining fresh water. © 2025 Society of Chemical Industry.

Well-defined poly[(methyl acrylate)-co-(hydroxyethyl acrylate)]-graft-poly(ε-caprolactone) copolymers were synthesized using a completely metal-free strategy by combining atom transfer radical polymerization (ATRP) and ring-opening polymerization (ROP) at ambient temperature. These two orthogonal, metal-free, controlled/living processes, tested in both simultaneous and sequential approaches, were employed to fine-tune grafting density and efficiency by systematically varying monomer concentration and polymerization time. Spectroscopic and chromatographic characterizations confirmed that both ATRP and ROP proceeded in a controlled fashion, yielding graft copolymers with narrowly distributed molecular weights. © 2025 Society of Chemical Industry.