Macromolecular Rapid Communications最新文献

The lithium-ion batteries increasingly require separators that combine high thermal stability, low swelling, and excellent electrolyte wettability, yet conventional ceramic coatings add weight and reduce porosity while acrylate-based polymer coatings often lack heat resistance. Here, we report a rationally engineered class of highly crosslinked, monodisperse polymeric microspheres synthesized via emulsion polymerization of styrene (St), methyl methacrylate (MMA), acrylonitrile (AN), and dipentaerythritol hexaacrylate (DPHA). The synergistic monomer design confers controlled particle nucleation, high thermal robustness (T₃ up to 370°C), and exceptional resistance to electrolyte swelling (<11%). When applied as thin (∼1.5 µm) separator coatings, the microspheres pack into uniform, porous, and strongly wettable architectures that significantly enhance separator performance. The coated separators exhibit minimal thermal shrinkage (5.6% at 150°C), more than double the electrolyte infiltration of ceramic-coated controls, and markedly improved ionic conductivity (0.80 mS cm^{- 1}). Pouch cells assembled with these separators deliver superior cycling stability and rate capability. This work establishes a high-performance, lightweight, and scalable alternative to ceramic coatings for next-generation lithium-ion battery separators.

The fabrication of physiologically relevant microvascular networks remains a major challenge in Organ-on-a-chip (OoC) technologies, largely due the dependence on plastic materials and the generation of channels with non-physiological, rectangular cross-sections. Here, we present a novel approach for the in-situ generation of perfusable micro-vessels within OoC platforms using freeform printing (FFP) of the thermo-responsive poly(2-cyclopropyl-2-oxazoline) (PcycloPrOx). We integrated FFP with a fluidic custom-designed OoC device to directly print suspended sacrificial vascular templates, enabling the creation of circular cross-section channels with resolutions down to 200 µm, without post-processing. Following hydrogel casting and template dissolution, green fluorescent protein human umbilical vein endothelial cells (GFP-HUVECs) were seeded into the channels and cultured under continuous perfusion (unidirectional and bidirectional) for 7 days. Confocal fluorescence microscopy revealed rapid endothelialization, with a confluent monolayer established by day 3. By day seven, immunostaining confirmed expression of endothelial markers CD31 and VE-cadherin, indicating proper endothelialization. This work demonstrates the first functional application of PcycloPrOx-based FFP for OoC vascularization and provides a scalable, automatable strategy for engineering perfusable, endothelialized microvascular 3D tissue models. Our platform offers new opportunities for vascularized organ-on-chip models in drug screening and disease modelling.

This study aims to evaluate the use of polyvinyl alcohol (PVA) moulds for the fabrication of cell-containing hydrogel scaffolds exploiting a bottom-up tissue engineering (TE) approach. To this end, different gelatin derivatives are functionalized and their physical gelation behaviour are investigated. The modified recombinant collagen peptide (RCPhC1) materials exhibit lower viscosity than the animal-derived gelatin, rendering them unsuitable to be exploited in extrusion-based 3D printing. Hence, indirect printing using water-soluble PVA moulds is explored, and the moulds demonstrate excellent water solubility, biocompatibility and photo-transmittance. The obtained scaffolds show a computer-aided design/computer-aided manufacturing (CAD/CAM) mimicry of ∼110% and mass swelling ratios (4-24) suitable for soft TE applications. Moreover, mechanical properties in line with those of native fatty tissue (Young's moduli 0.8-2 kPa) were obtained. The cell viability remains high (>80%) throughout the 14-day assessment period, indicating the biocompatibility of the encapsulated adipose tissue-derived stem cells (ASCs) within the scaffolds, irrespective of the applied hydrogel materials, being gelatin-methacryloyl (Gel-MA), gelatin norbornene/thiolated gelatin (Gel-NB/SH), RCPhC1-MA and RCPhC1-NB/SH. In conclusion, PVA moulds can be exploited to shape gelatin derivatives while ensuring cell compatibility. As a result, viscosity challenges can be overcome enabling the application of low viscous (<30 mPa.s) photo-crosslinkable hydrogels in extrusion-based 3D-printing serving TE applications, offering control over the scaffold architecture and cell behaviour.

Isotactic polybutene-1 (PB-1) shows peculiar crystallization behavior during crystallization from the melt, the metastable form II is always obtained. During aging at room temperature, the metastable crystals further undergo a solid-solid transition into the stable form I with a corresponding change in volume. Therefore, direct formation of the stable crystalline form I' in PB-1 has attracted significant attention in research. In this work, we report a molar mass (M_w) dependency of polymorph selection in PB-1 under compressed carbon dioxide (CO₂). PB-1 with a lower M_w exhibited a larger fraction of form II than the higher M_w PB-1 at the same CO₂ pressure, and the former required a higher pressure to completely suppress the formation of form II. It was shown that differences in chain morphologies in the formed crystals played a decisive role in polymorph selection. PB-1 with a lower M_w crystallized into form II with chain-extended crystals, whereas PB-1 with a higher M_w crystallized into form II with folded-chain crystals. A lower nucleation free energy barrier was expected in the former than in the latter, weakening the suppression of form II in a lower M_w PB-1 under compressed CO₂.

Shape memory polymers and their composites are promising smart materials for a wide range of applications associated with smart material-based actuators. Carbon fiber-reinforced shape memory epoxy composites can enable electroactive shape recovery via Joule heating, offering precise, remote-controlled actuation. However, predicting time-dependent recovery behavior across varying current levels remains challenging due to limited experimental data. This study presents an overfitting-aware machine learning framework for predicting shape recovery angles of the shape memory epoxy composites activated by Joule heating as a function of time and applied current. Four regression algorithms: Random Forest (RF), Support Vector Regression (SVR), Regularized Polynomial, and Gaussian Process Regression (GPR) are considered for constructing the shape memory recovery angle prediction algorithm. In the models, overfitting constraints are integrated into Bayesian hyperparameter optimization using a hybrid objective function that penalizes excessive generalization gaps. Stratified fivefold cross-validation ensures balanced current distribution across folds. Results demonstrate that kernel-based methods outperform tree ensembles: SVR achieves the highest accuracy with controlled generalization (R² = 0.944) while RF exhibits limited effectiveness (R² = 0.842), confirming tree-based methods are less suitable for small, smooth datasets. SVR provides optimal accuracy-generalization balance for reliable engineering predictions.

We report the first discovery of polymer single crystal whiskers with a fundamentally unprecedented architecture: prismatic poly(p-benzamide) (PBA) whiskers with practical dimensions (∼17 µm length, ∼1 µm width, ∼0.5 µm thickness). Within these whiskers, polymer chains are oriented perpendicular to the long axis while maintaining high crystallinity. This morphology diverges from conventional lamellar structures, representing a new class of staggered polymer crystalline architecture where adjacent chains interpenetrate without layered periodicity. The configuration exposes chain ends at whisker surfaces, significantly enhancing dispersibility in organic solvents and polymer matrices due to the high-energy surface. Composites incorporating these whiskers exhibit uniform microstructures, exceptional thermal stability, and high modulus. PBA whiskers offer a lightweight, organic alternative to traditional inorganic fillers. These findings not only introduce a sustainable strategy but also redefine structural design principles in polymer crystallography for high-performance materials via self-organization pathways.

Allyl glycidyl ether and 2-methoxyethyl glycidyl ether were copolymerized via anionic ring-opening polymerization and subsequently functionalized with guanidinium and indole groups through a post-polymerization thiol-ene reaction. This modular approach yielded eight polymers with systematically varied hydrophilic-hydrophobic balance, carrying 50-92 mol% guanidinium and 0-22 mol% indole. The polymers featured molar masses between 10.1 and 15.7 kg/mol with a dispersity of around 1.3. Polyplexes were formulated using plasmid DNA and characterized with respect to their physicochemical properties including DNA binding affinity, surface charge, and particle size as well as their transfection efficiencies and polymer in vitro cytotoxicity. All polymers were able to form stable complexes and protected their cargo against enzymatic degradation. An additional hydrophilic monomer did not influence physicochemical characteristics, but increased polymer cytotoxicity. Transfection studies in CHO-K1 cells revealed a strong dependence on polymer hydrophobicity: polymers with medium indole content outperformed both more hydrophilic and more hydrophobic analogues, reaching efficiencies above the gold standard poly(ethylene imine). These results underline the critical role of balancing hydrophilic and hydrophobic groups in side-chain functionalized poly(glycidyl ether)s for safe and effective gene delivery.

Organic electrochemical transistors (OECTs) offer unique advantages for bioelectronic and neuromorphic applications. The development of n-type enhancement-mode devices is essential for creating complementary circuits and low-power, bidirectional bioelectronic platforms. However, progress in this area has been hindered by the challenges associated with processing suitable n-type polymers. Here, we present a nanoparticle-based processing strategy for the ladder polymer poly(benzimidazobenzophenanthroline) (BBL). This n-type mixed conductor is soluble only in strong acids, which hinders straightforward fabrication. BBL nanoparticles are obtained by reprecipitation with an anionic surfactant, and systematic analysis reveals a particle-number-controlled scaling law, in which surfactant concentration and the polymer-to-surfactant ratio govern stabilization. Films prepared from these dispersions further underscore the importance of nanoparticle assembly: spray-coating yields dense, interconnected networks with markedly higher electrochemical activity than the porous films obtained by the filtration-transfer method. The spray-coated BBL films operate in enhancement mode, exhibiting efficient switching in the subthreshold regime while remaining non-conductive at zero gate bias. This work establishes a scalable route to n-type enhancement-mode OECTs, thereby broadening the foundation for next-generation bioelectronic and neuromorphic systems.

Precise spatial confinement of enzymes at oil-water interfaces offers an elegant strategy to enhance biphasic catalysis yet achieving robust and recyclable interfacial assemblies remains challenging. Here, we introduce an amphiphilic polymeric Janus particle platform that enables lipases to preferentially localize at interfaces, thereby achieving efficient Pickering interfacial catalysis (PIC). Crosslinked poly(hydroxypropyl methacrylate) colloids bearing surface carboxylic acid groups were synthesized via RAFT-mediated heterogeneous copolymerization and further transformed into snowman-shaped Janus particles through seeded emulsion polymerization. The resulting amphiphilic Janus colloids possess distinct hydrophilic-hydrophobic domains that facilitate both enzyme anchoring and emulsion stabilization. Candida rugosa lipase (CRL) immobilized on these particles exhibited strong interfacial activity, achieving enhanced catalytic efficiency, thermal stability, and recyclability compared to free CRL. The present work suggests that enzyme immobilization on Janus colloids is a promising approach to advance next-generation PIC.