RSC Applied Polymers最新文献

Foldable platforms have huge potential in the field of plasmonic engineering thanks to their ability to dynamically reconfigure surface geometries, enabling precise spatial control over nanoscale electromagnetic interactions. Herein, we demonstrate the design and fabrication of light-induced foldable polystyrene (PS) platforms functionalized with plasmonic nanostructures for dynamic control of electromagnetic hot-spot generation and surface-enhanced Raman scattering (SERS) applications. The self-folding behavior of the platforms was actuated via infrared (IR) irradiation, with folding angles modulated by hinge geometry and exposure time. Multi-armed PS platforms were engineered to transform from 2D to 3D configurations, enabling precise spatial localization of analyte molecules through geometric reconfiguration. Plasmonic hot-spot generations were investigated by decorating the platform surfaces with colloidal gold nanoparticles (AuNPs), nanourchins (AuNOs), and nanorods (AuNRs), as well as through the integration of 3D-oriented AuNR assemblies fabricated via the oblique angle deposition method. SERS measurements using methylene blue (MB) demonstrated substantial signal enhancements upon folding, with 3D-AuNR assemblies yielding superior performance due to their anisotropic and ordered architecture. A proof-of-concept application of pesticide detection from a tomato surface validated the integrated platform's capabilities for remote actuation, target collection, and ultrasensitive detection. This work highlights the potential of programmable polymeric actuators as scalable, untethered sensing devices for real-world analytical applications.

The development of light weight polymeric materials with high strength and toughness is a growing research focus. Traditional chemical cross-linking techniques, while improving strength, generally compromise toughness. Particle-based cross-linkers, including small molecules, nanoparticles, or polymer aggregates, on the other hand, can form multiple hydrogen-bonded networks with polymer chains, thereby simultaneously enhancing strength and toughness. In addition to highlighting recent advancements in engineering such networks, this short review addresses the effects of different particle types on the mechanical properties of polymers and highlights key design strategies, performance improvements, and industrial opportunities.

Vitrimers represent a promising class of new-generation materials with covalent adaptive networks (CANs) based on an associative exchange mechanism. Herein, we utilised epoxy-functionalized elastomers, like poly(ethylene-co-vinyl acetate-co-glycidyl methacrylate) (EVA-GMA), for designing a dual dynamic network based on β-hydroxyl ester linkage as well as disulfide metathesis reactions, which were enabled by a new crosslinker, succinic anhydride-modified 4-aminophenyl disulfide (SA-APDS), which has a disulfide linkage in the backbone and a –COOH group at the para position. These dynamic linkages are capable of undergoing exchange reactions at elevated temperatures, thereby allowing the rearrangement of the network topology and exhibiting vitrimer-like behaviour. The resultant elastomeric vitrimer exhibits good mechanical performance, including a tensile strength of ∼6.1 MPa and elongation at break up to 1300%, demonstrating super-elastomeric characteristics. Interestingly, the elastomeric vitrimer showed fluorescence behaviour due to the presence of a conjugated system in the new crosslinker. The ability of this material to maintain and reconfigure crosslink density through dual associative mechanisms showed that vitrimer-like materials have self-healing, recyclable, and reprocessable characteristics. Stress relaxation experiments confirmed the vitrimeric behaviour with an activation energy of 46.8 kJ mol⁻¹ and a vitrification temperature of 83 °C. This new vitrimeric elastomer, with fluorescence characteristics, can have potential applications in areas where a unique combination of mechanical and optical properties is necessary.

Achieving biodegradable and functional food packaging with enhanced mechanical resistance, barrier efficiency, and bioactive properties remains a challenge. This study investigates the incorporation of natural eutectic solvents (NAES) as a strategy to improve the performance of pectin-based films. These NAES, composed of choline chloride (ChCl) and tannic acid (TA) or citric acid (CA), were added at concentrations of 67 and 80 wt% to develop materials suitable for food packaging applications. The films were fabricated via a casting method, and their structural, physicochemical, and functional characteristics were thoroughly analyzed. Results revealed that NAES played a key role in reinforcing the mechanical properties of the films, increasing their tensile strength from ≈0.75 MPa in the control samples to ≈2.2 MPa. Additionally, the presence of NAES significantly improved the films’ capacity to block UV radiation, particularly in the 200–350 nm range, which is crucial for preserving light-sensitive food products like polyunsaturated oils. Environmental sustainability was also confirmed through biodegradation assays, where the films exhibited an 80% weight loss after 20 days in soil. Furthermore, antimicrobial properties conferred by NAES effectively inhibited the growth of E. coli and S. aureus, with inhibition zones surpassing 15 mm. When applied to food preservation, the films provided remarkable oxidative protection to chia oil, reducing hydroperoxide levels from approximately 57 to 7.5 meqO₂ kg⁻¹ oil, while extending the oxidation induction period from 0.25 to ≈4.6 hours over 25 days of storage in oxidative accelerated conditions. These findings underscore the potential of NAES as active additives that enhance the properties of biopolymer-based films while imparting bioactive functionality, paving the way for sustainable and efficient food packaging solutions.

As ancient Earth creatures, scorpions have adapted well to various complex living environments after hundreds of millions of years of biological evolution. Their exoskeleton (cuticle) emits blue-green bioluminescence under UV radiation. This paper studies the synthesis and properties of poly(butyl acrylate-co-N-isopropylacrylamide) (PBN-MDE) film doped with the scorpion's fluorescent molecule macrocyclic diphthalate ester (MDE). The MDE fluorescent molecules can form dynamic hydrogen bonds with the PBN polymer chain, greatly enhancing its mechanical properties, with specific ductility and toughness nearly ten times before doping. In addition, the PBN-MDE film not only has excellent visible light transmittance and can display obvious fluorescence under UV light (365 nm), but also exhibits preeminent UV shielding efficiency (<400 nm) and good bacteriostatic activity for Gram-positive bacteria and Gram-negative bacteria. These special functions of the PBN-MDE film can effectively extend its service life and are expected to achieve UV-resistant coatings with functions such as information protection, adaptive camouflage, or information transmission.

Stimuli-responsive hydrogels have gained significant attention in wound care due to their ability to adapt to dynamic physiological conditions, making them promising candidates for facilitating chronic wound healing. These hydrogels can respond to both internal and external environmental stimuli such as temperature, pH, reactive oxygen species (ROS), glucose levels, MMP, mechanical forces, magnetism, and ultrasound, enabling precise, on-demand therapeutic interventions through controlled drug release. This responsiveness is governed by reversible changes in their polymer network structure caused by interactions with external stimuli. By creating an optimized environment for wound healing, stimuli-sensitive hydrogels can promote moisture retention, cellular migration, and mechanical flexibility while accelerating critical tissue repair processes like angiogenesis or collagen synthesis. Additionally, incorporating bioactive agents such as antimicrobial compounds, growth factors, and other therapeutically active substances like honey, has further expanded their functionality, though such modifications may be secondary to their inherent stimuli-responsive nature. This review provides a comprehensive overview of recent advancements in stimuli-responsive hydrogels for chronic wound management, highlighting their ability to respond to environmental cues and addressing their potential to enhance healing through the controlled release of therapeutic agents, promotion of hemostasis, and tissue regeneration.

Microporous organic polymers (MOPs) have garnered significant attention in recent years due to their unique structural and functional properties. Among them, hypercrosslinked polymers (HCPs) are particularly promising for environmental applications, including the removal of organic contaminants from water. In this study, we report the synthesis of a novel HCP, designated as PBFC, constructed via Friedel–Crafts knitting alkylation of fluorenone and benzene. Post-synthetic functionalization of PBFC with 1,3-diaminopropane yielded an amine-functionalized polymer, PBFA. The adsorption performance of both polymers was evaluated for the removal of bisphenol-A (BPA) from aqueous solutions. Notably, PBFA exhibited a high adsorption capacity of 130 mg g⁻¹, attributed to the presence of amine groups enhancing interaction with BPA molecules. Adsorption behavior followed the Langmuir isotherm and pseudo-second-order kinetic models, indicating monolayer chemisorption. Thermodynamic analyses revealed negative values of ΔG, ΔH, and ΔS, confirming the spontaneous and exothermic nature of the adsorption process. The dominant adsorption mechanisms were identified as hydrogen bonding, π–π interactions, and hydrophobic interactions. These findings highlight the potential of amine-functionalized HCPs as efficient adsorbents for organic pollutant removal from water.

Poly(vinyl alcohol) (PVA) is commonly used in a wide variety of applications due to its desirable characteristics. However, limitations exist regarding its solubility and mechanical properties. To address this, the gelation of syndiotactic-rich polyvinyl alcohol (sPVA) with a regular three-dimensional structure was performed using an organic solvent-free approach. The obtained sPVA exhibited a higher crystallinity than the commonly used atactic PVA (aPVA). However, both systems exhibit low solubilities in solvents such as water and dimethyl sulfoxide due to their high crystallinities, thereby rendering it impossible to exploit their properties. However, since the hot pressing method does not require the dissolution of PVA in a solvent, it is possible to perform gelation using sparingly soluble materials such as sPVA. Consequently, a hydrogel was formed by applying the hot pressing method to water-swollen sPVA. The obtained sPVA hydrogel (sPVA-H) was subsequently dried and heat-treated at different temperatures to compare its crystallinity and thermal and mechanical properties with those of the aPVA hydrogel (aPVA-H). It was found that sPVA-H exhibited comparable properties to the original sPVA-H following heat treatment at higher temperatures, and also when heat-treated at a temperatures lower than those required for aPVA-H. The obtained results indicated that sPVA-H exhibits excellent mechanical properties, suggesting its potential for incorporation in materials for long-term loading applications, such as artificial cartilage.

Developing a straightforward and efficient strategy for incorporating functionality in porous materials is of paramount importance. Functionality can endow these materials with enhanced performance in established applications or enable new performances in emerging application domains. Herein, we present the synthesis of a pyrazole-containing porous organic polymer (PPOP) via a multicomponent tandem polymerization reaction involving tetrakis(4-ethynylphenyl)silane, terephthaloyl chloride, and hydrazine hydrate. The integration of pyrazole units into a porous network bestows new functionality on PPOP and leads to excellent iodine capture performance and suitable support for silver nanoparticles, which can act as an efficient catalyst for nitro reduction reactions. PPOP exhibits an iodine vapor adsorption capacity of 3.52 ± 0.15 g g⁻¹, which is comparable to or higher than many existing iodine adsorbents. Mechanistic investigations reveal that the adsorption is governed by a combination of physisorption and chemisorption. Chemisorption is facilitated by electron transfer from electron-rich moieties, particularly pyrazole groups, within the adsorbent to I₂, leading to the formation of polyiodides and charge-transfer complexes. When loaded with silver nanoparticles, PPOP can catalyze the reduction reactions of nitroaromatics to aminoaromatics with nearly complete conversion within 20 min at room temperature. This research underscores the utility of multicomponent tandem polymerization reactions for the rational design and synthesis of functional POPs with potential applications in diverse fields.

Because of their unique properties, ionogels are very suitable for wide application in fields such as energy storage devices and wearable devices, but poor mechanical strength limits their practical use. Polyols or compounds containing multiple unsaturated double bonds are typically used as cross-linking agents in the construction of gels, but it is difficult to balance mechanical strength with flexibility because these compounds mainly form linear or simple reticular structures. It is, therefore, important to design ionogels with improved mechanical properties. Here, response surface methodology was used to optimize the preparation of light-curing ionogels, using the biomass-derived polymer rutin as an antioxidant cross-linking agent. The prepared ionogels had a tensile strength as high as 639.15 kPa, which was attributed to the three-dimensional cross-linked network structure formed by esterified rutin and to the sacrificial hydrogen bond energy dissipation mechanism. After light curing of the esterified rutin by free radical polymerisation, the structure retained the intact conjugated system and thus provided good UV protection (light transmission in UVB region = 0%). This study offers a new way to rapidly prepare high-performance UV-resistant polymer coatings, which show promise for applications in sunscreen coatings, such as parasols and automotive/architectural sunscreen glass.