Macromolecular Rapid Communications最新文献

A simple one-step photopolymerization strategy is presented to fabricate multifunctional shape-memory polymer composites capable of remote and programmable light-triggered actuation. The composites integrate gold nanoparticles and semicrystalline poly(ethylene)-block-poly(ethylene oxide) nanoribbons within a cross-linked epoxy network. During curing, the block copolymer undergoes crystallization-driven self-assembly, generating micrometer-long nanoribbons that act as reversible thermal switching domains, while gold nanoparticles are simultaneously formed in situ, enabling efficient conversion of visible light into localized heat through plasmonic excitation. Spectroscopic and microscopic analyses confirm the successful incorporation of both components without compromising their native morphology. Differential scanning calorimetry reveals two distinct thermal events corresponding to the glass transition of the epoxy matrix and the melting of the polyethylene domains, providing two independently addressable switching temperatures. Under green-light irradiation, the embedded gold nanoparticles rapidly raise the local temperature, enabling not only remote activation of the shape-memory effect but also programmable sequential shape recovery by selectively activating each thermal transition through laser power adjustment. These results demonstrate that combining crystalline block copolymer nanostructures with plasmonic nanoparticles enables remotely controlled multi-stage actuation using a single external stimulus. This scalable and ambient-compatible approach provides a versatile platform for the design of light-responsive composites with tunable thermal and mechanical behavior, offering opportunities for applications in smart coatings, remote actuators, and programmable materials.

Pure organic room-temperature phosphorescence (RTP) polymers have attracted considerable attention for their promising applications in information encryption, anti-counterfeiting, and flexible optoelectronics. Herein, we report a strategy combining physical blending and in situ covalent cross-linking to fabricate processable RTP polymer blends with ultrawide mechanical tunability. Flowable precursors are first prepared by dispersing carbazole-based phosphor-doped polystyrene (PS) into polyethylene glycol (PEG), followed by cross-linking of terminal hydroxyl groups to form a three-dimensional polyurethane network that provides an excellent oxygen barrier and shape fixation. The optimized system exhibits bright yellow RTP with afterglow durations of 1.7–5.5 s, representing a 2–5-fold enhancement compared with non-cross-linked systems. Impressively, Young's modulus can be precisely tuned over 9 orders of magnitude from ∼10⁻¹ to ∼10⁸ Pa. This work provides a universal and scalable route for developing moldable, mechanics-tunable RTP polymers for advanced optical and anti-counterfeiting applications.

Polyimides (PIs) are widely used as advanced substrates due to their excellent thermal and mechanical properties. However, conventional petroleum-based aromatic PIs suffer from intrinsic coloration arising from charge-transfer complex (CTC) formation, limiting their optoelectronic applications. In this study, two camphor-derived alicyclic diamines (CA and CM) were synthesized, along with a reference isosorbide-derived diamine (IS). These monomers were polymerized with 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CB) and a tetracarboxylic dianhydride featuring a cyclopentanone bis-spironorbornane structure (Cp) to prepare six biobased CPIs. Their favorable optical transparency arises from the combined contribution of the non-conjugated dianhydride structures and the alicyclic camphor-derived diamine structures. The structure–property relationships of the biobased CPIs were systematically investigated. The CA series exhibits limited film-forming ability because of its highly rigid molecular structure. In contrast, incorporating a methylene spacer into the CM series enhanced chain flexibility, leading to improved film-forming ability and overall film quality. Among the prepared CPIs, CM–CB exhibited the most balanced performance, achieving 60% biomass content, optical transparency (T₄₀₀ = 82% and YI = 3), and a glass transition temperature above 300°C. These results suggest that camphor-derived diamines can serve as useful biobased units for developing CPIs with balanced optical transparency and thermal properties.

Schiff base derivatives, namely 3-(((2-hydroxynaphthalen-1-yl)methylene)amino)-1-phenyl-1-pyrazole-5-one (3-APPHNA) and 4-(((2-hydroxynaphthalen-1-yl)methylene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3-one (4-APPHNA), were synthesized via the condensation reaction of 3-amino-1-phenyl-2-pyrazolin-5-one (3-APP) and 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one, (4-APP) with 2-hydroxynaphthaldehyde (2-HNA) in ethanol. Synthesized monomers were then converted into their oligomeric derivatives via oxidative polycondensation carried out using NaOCl. The structural, thermal, optical, electrochemical, and morphological properties of the obtained monomers were comprehensively characterized using fourier transform infrared (FT-IR), proton nuclear magnetic resonance (¹H-NMR), carbon-13 nuclear magnetic resonance (¹³C-NMR), ultraviolet-visible spectrophotometer (UV–vis), thermogravimetry-derivative thermogravimetry (TG-DTG), and cyclic voltammetric analyses. Spectroscopic studies confirmed the successful synthesis of Schiff bases and the presence of stable azomethine bonds. Molecular weight, glass transition temperature, and surface morphologies of oligomers were determined by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and field emission scanning electron microscope (FE-SEM) measurements, respectively. The M_n values of oligo(3-APPHNA) and oligo(4-APPHNA) were found to be 3400 and 2900 Da, respectively. The results revealed an oxidative oligomerization process yielding relatively narrow molecular weight distributions. Oligo(4-APPHNA) has shown more pronounced semiconductor properties compared to other oligomers, considering its 2.30 eV optical band gap and frequency-dependent electrical behavior. Additionally, dielectric measurements showed that oligo(4-APPHNA) exhibited higher dielectric constant, dielectric loss, and AC conductivity values throughout the investigated frequency range. These findings suggest that the synthesized oligomers are promising candidate materials for future optoelectronic and semiconductor applications, but further research at the device level is needed.

Fiber-reinforced elastomers can significantly enhance mechanical strength while retaining material softness, thereby expanding the application scope of elastomeric materials in scenarios requiring both high flexibility and high strength. Compared with thermoplastic polymers and ceramic materials, elastomers exhibit low modulus and high fracture strain, which result in more complex fiber–matrix interfacial behaviors. This review systematically elucidates the intrinsic relationships between microscopic stress transfer mechanisms and macroscopic mechanical properties in fiber-reinforced elastomers, summarizes research progress in this field over the past two decades, and highlights the effects of various reinforcement strategies on performance optimization, providing a theoretical basis for the design and development of next-generation high-performance fiber-reinforced elastomers.

UV absorbers are essential for long-term durability, yet boosting UV absorption without visible coloration presents a classic trade-off. We present an automated, high-throughput design platform that balances these objectives by optimizing site–substituent patterns on a benzophenone (BP) scaffold. Solar-weighted kinetic metrics quantify the UV-band rate constant (k_UV) and the visible-band rate constant (k_vis). Guided by favorable site–substituent rules, a focused design yields candidates with high k_UV and near-zero k_vis. The lead candidate is identified as a high-potential candidate, with a predicted k_UV = 5.28 × 10⁻³ s⁻¹ (≈ 260 × that of commercial BP, 2.06 × 10⁻⁵ s⁻¹) with an estimated negligible visible absorption. Compared with BP, the leader one exhibits a broad, strong absorption band in the 275–350 nm range, yielding extended and enhanced UV absorption. These results overturn the perceived trade-off between high UV absorption and colorlessness. The platform provides rapid, computationally-informed design directions that shortens development cycles and reduces costs, replacing ad hoc few-molecule computations with a generalizable, reusable framework across polymer systems.

Dielectric polymers with high glass transition temperatures (T_g) are widely employed in capacitive energy storage applications for electronic equipment and power systems. However, polyetherimide (PEI) suffers from significant leakage current and a pronounced increase in conductivity loss at high temperatures, which prominently restricts its operational reliability under extreme conditions. In this work, an all-organic strategy is proposed by random blocking the 2, 2-Bis [4-(4-aminophenoxy) phenyl] propane (BAPP) into the PEI backbones. The staggered potential barriers between distinct chains create local electronic trap states and increase the energy barrier for trapped carriers to escape. Furthermore, the incorporation of the BAPP segments effectively decreases the interchain spacing and fractional free volume (FFV). Experimental studies and density functional theory (DFT) calculations reveal that a large number of deep traps combined with a reduced FFV, enhance electron capture capability and restrict charge transport. As a result, the random copolymer with 50 mol% BAPP segments (C50PEI) exhibits superior high-temperature capacitive performance, delivering an exceptional discharged energy density (U_e) of 4.68 J/cm³ with a charge–discharge efficiency (𝜂) exceeding 90% at 200°C. This work provides an all-organic design strategy for the development of dielectric capacitors under extreme high-temperature conditions.