Janus vesicles, unique nanostructures, have attracted significant attention for their diverse applications in biomedical and microfluidic systems. In practical micro-nano systems, flow and electric fields often coexist, and the perforation dynamics of Janus vesicles exhibit complex motion due to their synergistic effects. Studying Janus vesicle perforation dynamics under the combined influence of fluid flow and electric fields provides valuable insights into their applications in drug delivery, catalyst delivery, and controlled release. This study focuses on the perforation dynamics and directional motion of Janus vesicles in microchannels, emphasizing how electric field strength and charge distribution on the membrane influence vesicle migration, deformation, and trajectories. Results show that when electromagnetic forces and flow-driven forces align, increasing electric field strength promotes vesicle migration and perforation. Vesicle migration is correlated with charge distribution on the membrane, with broader distributions resulting in more pronounced migration. When electric field strength remains constant, charge distribution has little effect on vesicle deformation. Conversely, when electromagnetic forces and flow-driven forces oppose, increasing electric field strength inhibits vesicle migration. At a specific potential difference, charged vesicles cease movement before reaching the perforation site, indicating the critical potential for perforation. The study also reveals that the direction of the electric field significantly affects vesicle migration direction. Adjusting potential values at microchannel boundaries can control the directional movement of Janus vesicles. This research provides new insights into Janus vesicle behavior in complex environments and deepens understanding of their potential as drug carriers for delivery and targeted therapy.

Ultrasound (US), as an efficient and non-invasive trigger, has been extensively explored in drug delivery and has many advantages, such as deep penetration, low invasiveness, and high biochemical precision. These advantages demonstrate the immense clinical potential of ultrasound. This study aimed to provide a comprehensive analysis of ultrasound-induced shear forces that exhibit covalent/non-covalent bond cleavage and reactive oxygen species (ROS)-mediated remote control of nanocarriers. By doing so, we can gain a deeper understanding of the vital role, significant advantages, and untapped potential of ultrasound in molecular-level drug activation. Furthermore, clinical translation faces challenges such as the low drug-loading capacity of polymer chains, frequency compatibility between ultrasound parameters and biological systems, insufficient ROS generation, and biocompatibility of current sonosensitizers. To solve these problems, ultrasound mechanochemistry has emerged as a versatile therapeutic modality to promote the development of medical treatments.

The [2+2] photopolymerization of bisolefinic monomers is an important method for the synthesis of polymeric materials. However, these processes are usually carried out in solid states under the irradiation of high-energy UV light, while the corresponding [2+2] polymerization in solution has proved to be inefficient due to the lack of preassembly of the monomers. Herein, we demonstrate that the [2+2] polymerization of p-phenylenediacrylate monomers can be achieved in solution under visible light by employing energy transfer catalysis with 2,2’-methoxythioxanthone as a photocatalyst. Because no preassembly is required, this solution polymerization is applicable to p-phenylenediacrylate monomers with different ester groups, affording a series of cyclobutane-imbedded full-carbon chain polymers with high thermal stability, good solubility, and processibility. In addition, by virtue of the reversibility of the photo [2+2] cycloaddition, this [2+2] photopolymerization product can also undergo depolymerization to lower molecular weight polymers, suggesting the potential of this class of photopolymerization in the development of closed-loop chemical recyclable polymers.

This work proposes a bioinspired hierarchical actuation strategy based on liquid crystal elastomers (LCEs), inspired by the helical topological dynamic adaptation mechanism of plant tendrils, to overcome the bottleneck of precise anisotropic control in LCEs. Mechanically pre-programmed hierarchical LCE structures responsive to near-infrared (NIR) light were fabricated: the oriented constrained actuator achieves asymmetric contraction under NIR irradiation, enabling reversible switching between helix and planar morphologies with multi-terrain grasping capability; the biomimetic vine-like helical actuator, composed of Ag nanowire photothermal layers combined with helical LCE, utilizes temperature-gradient-induced phase transition wave propagation to achieve NIR-controlled climbing motion; the Möbius topology actuator realizes reversible deformation or self-locking states by tuning the twist angle (180°/360°); based on these, a bioinspired koala-like concentric soft robot was constructed, successfully demonstrating tree trunk climbing. This study reveals that artificial helical stretching significantly enhances the molecular chain orientation of LCEs (surpassing uniaxial stretching), reaching up to 1000% pre-strain, and the AgNWs/LCE/PI (Polyimide) tri-layer structure achieves efficient photothermal-mechanical energy conversion via localized surface plasmon resonance (LSPR). This study provides a new paradigm for soft robotics material design and topological programming, demonstrating the potential for remote operation and adaptive grasping.

4D-printable shape memory polymers (SMPs) hold great promise for fabricating shape morphing biomedical devices, but most existing printed polymers either require harsh activation conditions or lack sufficient mechanical strength for vascular implantation. Here, we report a dual-stimuli-responsive shape memory polymer system enhanced by acrylated Pluronic F127 (PF127-DA) micelles, which can be fabricated using digital light processing (DLP) based 3D printing. The PF127-DA based nanoscale micelles, which are formed via self-assembly in the hydrogel ink for 3D printing, act as crosslinkers to improve mechanical strength, fatigue resistance and elastic recovery. After drying the printed hydrogel, the obtained SMPs exhibit excellent shape recovery behaviour under mild physiological conditions—specifically body temperature (37 °C) and aqueous swelling—resulting in recovery stress up to about 150 kPa. This swelling-assisted actuation enables effective radial support, making the printed constructs suitable for vascular use. In vitro cytocompatibility assays with NIH/3T3 fibroblasts confirmed the suitable biocompatibility. Furthermore, the self-expanding behavior of the printed stents was validated in an occluded vessel model under physiological conditions. These results demonstrate the feasibility of 4D printed micelle-enhanced SMP for patient-specific, minimally invasive vascular stents and other soft implantable devices requiring high recovery force under physiological stimulation.

The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability. However, conventional polypeptide synthesis from the polymerization of N-carboxyanhydride (NCA) is conducted at relatively slow rates, requiring long tubing or ending up with low-molecular-weight polymers. Inspired by recent advances in accelerated NCA polymerization, we report the crown-ether-catalyzed, rapid synthesis of polypeptide materials in cosolvents in flow reactors. The incorporation of low-polarity dichloromethane and the use of catalysts enabled fast conversion of monomers in 30 min, yielding well-defined polypeptides (up to 30 kDa) through a 20-cm tubing reactor. Additionally, random or block copolypeptides were efficiently prepared by incorporating a second NCA monomer. We believe that this work highlights the accelerated polymerization design in flow polymerization processes, offering the continuous production of polypeptide materials.

The most widely used bisphenol A-type epoxy resin (DGEBA) in electrical engineering demonstrates excellent mechanical and electrical properties. However, the insoluble and infusible characteristics of cured DGEBA make it difficult to efficiently degrade and recycle decommissioned electrical equipment. In this study, a degradable itaconic acid-based epoxy resin incorporating dynamic covalent bonds was prepared through the integration of ester bonds and disulfide bonds, with itaconic acid as the precursor. The covalent bonding effects on the mechanical, thermal, electrical, and degradation characteristics were systematically evaluated. The experimental results revealed that the introduction of dynamic ester bonds enhanced the mechanical properties and thermal stability of the resin system, achieving a flexural strength of 141.57 MPa and an initial decomposition temperature T_5% of up to 344.9 °C. The resin system containing dynamic disulfide bonds exhibited a dielectric breakdown strength of 41.11 kV/mm. Simultaneously, the incorporation of disulfide bonds endowed the epoxy resin with remarkable degradability, enabling complete dissolution within 1.5 h at 90 °C in a mixed solution of dithiothreitol (DTT) and N-methylpyrrolidone (NMP). This research provides a valuable reference for the application of itaconic acid-based vitrimer with dynamic covalent bonds in electrical materials, contributing to the development and utilization of environmentally friendly electrical equipment.

In this study, dynamic selenonium salts were incorporated into a polyurethane (PU) matrix to develop transparent, healable and antibacterial coatings. Through systematic formulation optimization, optically clear materials with excellent room-temperature hardness were obtained. Fine-tuning the selenonium content established a synergy between antibacterial performance and network dynamics, as evidenced by vitrimer-like rheological behavior at elevated temperatures. Consequently, the coatings exhibited outstanding reprocessability while maintaining high transparency and structural stability after prolonged saltwater exposure. These integrated features underscore the potential of the developed cationic PU coatings as robust, multifunctional materials for electronic device protection and marine antifouling, combining long-term transparency, recyclability, and antibacterial durability.

In this study, an amine-reactive poly(pentafluorophenyl acrylate) (PPFPA) platform was developed for advanced surface engineering of next-generation sequencing (NGS) chips. Through post-polymerization modification, PPFPA was functionalized with dual moieties: azide groups for covalent immobilization of DBCO-modified DNA primers via click chemistry and tunable hydrophilic side chains to optimize biocompatibility and surface properties. Systematic screening revealed that hydrophobic azide carriers combined with neutral hydroxyl groups maximized the DNA immobilization efficacy, approaching the performance of commercial polyacrylamide-based polymers. The negatively charged carboxyl groups severely impede DNA primer attachment. Higher molecular weight derivatives further enhance the efficacy of DNA immobilization. In NGS validation, optimized surface modification polymers achieved robust surface density of clustered DNA and high sequencing accuracy, surpassing quality benchmarks and comparable to those of conventional analogs. This platform demonstrates significant potential for tailoring high-sensitivity surfaces for genomic applications, advancing clinical diagnostics, and personalized medicine.

Chitin, distinguished by its nitrogen-rich acetamido and amino groups, imparts a distinctive cationic nature, enabling chitin to have indispensable features in various applications. Despite its significant promise in the textile industry, particularly for sustainable and functional fabric applications, the practical utilization of chitin fibers remains constrained by insufficient mechanical strength. The degree of deacetylation (DD), a key molecular-level structural determinant, has not been adequately addressed in previous studies despite its critical role in influencing chitin properties across multiple scales. In this study, a deacetylation-mediated design strategy was used to achieve enhanced mechanical performance coupled with multifunctional efficacy using an aqueous KOH/urea solution dissolution system. We prepared a series of deacetylated chitins with different DD values and systematically studied the effect of deacetylation on the multiple-scale structure of regenerated fibers, such as intermolecular interactions and chain orientation at the molecular level, and the aggregation behavior of chitin nanofibers within the gel-state and dried fibers at the micro/nano scale. To achieve an enhanced mechanical performance coupled with multifunctional efficacy by relying on an aqueous KOH/urea solution dissolution system. Moreover, deacetylation enhances intermolecular interactions, resulting in densified internal structures and improved fiber orientation. Concomitantly, it augmented the antimicrobial functionality of the fibers. This deacetylation-mediated design strategy provides a deeper understanding of the structure and properties of regenerated chitin and advances the utility of chitin in strong and sustainable fibers.

Silibinin, a natural flavanone extracted from the milk thistle plant (Silybum marianum), has been shown to have various therapeutic applications, including liver protection, antioxidant, anticancer, anti-inflammatory, and many other effects. However, silibinin exhibits poor oral absorbance and low bioavailability owing to its limited water solubility, which limits its therapeutic efficiency and further clinical translation. To address these issues, we propose an antioxidant glycopolypeptide micelle strategy to target the delivery of silibinin to enhance its solubility, bioavailability, and antioxidant activity. This versatile micelle self-assembled from a glycopolypeptide, N-acetylgalactosamine-grafted poly(glutamic acid)-block-poly(tyrosine). N-acetylgalactosamine (GalNAc) is incorporated to enable liver targeting by selectively binding to the asialoglycoprotein receptor, which is overexpressed on hepatocellular carcinoma cells. The antioxidant polypeptide polytyrosine, as well as encapsulated silibinin, exhibits a synergistic reactive oxygen species (ROS) scavenging effect. The obtained results confirmed that silibinin can be effectively encapsulated into the glycopolypeptide micelles through self-assembly, achieving a loading efficiency and loading content of 96.6% and 42.9%, respectively. The silibinin-loaded glycopolypeptide micelles exhibited enhanced cellular uptake and a synergistic ROS scavenging effect in hepatocellular carcinoma cells. Overall, these antioxidant glycopolypeptide micelles hold promise as safe and efficient drug delivery systems for targeting hepatocellular carcinoma cells, potentially providing an effective strategy to enhance the bioavailability and antioxidant activity of silibinin.

Temperature-sensitive random copolymerized nanohydrogels were prepared via a one-pot polymerization method using N-isopropylacrylamide (NIPAM) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as raw materials. Transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) analyses revealed the partially crystallized porous nanostructure of the gels, which is consistent with the characteristics of porous nanohydrogel materials. The low-molecular-weight polymers exhibited enhancement and sharpening of the end group peaks in Fourier-transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance hydrogen (¹H-NMR) spectra due to the high proportion of small molecules or low-molecular-weight chain segments. In turn, the high-molecular-weight polymers showed pronounced peaks in the main chain segments because of the long-chain effect. Hygroscopicity increased with the molecular weight of the selected polymers, but was inhibited by temperatures below the lower critical solution temperature (LCST). Meanwhile, moisture desorption was faster in low-molecular-weight samples, and the overall moisture desorption rate rose above the LCST value. According to the kinetic analysis, the moisture absorption process conformed to the quasi-primary or quasi-secondary kinetic model, whereas the moisture desorption followed the quasi-secondary model. Moisture cycling experiments showed that the material maintained stable moisture absorption and desorption performance after several cycles, which is essential for long-term cycling.

The introduction of dynamic covalent bonds into the structure of epoxy resins can improve the degradation performance of the materials. But to a certain extent, it will affect the insulating properties of the resin, and how to balance the insulating properties and degradation performance has become an urgent problem. In this paper, the effects of different catalysts on the thermal-force-electrical properties of sorbitol-based resins were systematically investigated based on the dynamic ester bonding to construct the resin crosslinking network, and the biobased sorbitol glycidyl ether was used as the resin matrix. The experiments show that the resin system catalyzed by triethanolamine (TEOA) exhibits excellent comprehensive performance, which combines good thermal stability and mechanical properties with excellent electrical properties (breakdown field strength of 44.21 kV/mm and dielectric loss factor of 0.29%). In addition, chemical degradation tests were conducted on the resin systems with different catalysts, and the experiments showed that the produced resins could be degraded in benzyl alcohol and exhibited good degradation performance. This study provides a theoretical basis and technical path for the development of new bio-based electrical insulating materials with both high insulation and degradation properties, which is conducive to the popularization and application of bio-based resins in the field of electrical equipment.

Conductive hydrogels derived from natural polymers have attracted increasing attention in wearable electronics due to their inherent biocompatibility and sustainability. However, their poor mechanical strength, limited conductivity and unsatisfactory environmental adaptability remain significant challenges for practical applications. In this study, we report a high-performance gelatin-based conductive hydrogel (GPC) reinforced with polypyrrole-decorated cellulose nanofibers (PPy@CNF) and enhanced by a zwitterionic betaine/(NH₄)₂SO₄ solution. The PPy@CNF hybrid nanofillers were synthesized via in situ oxidative polymerization, enabling homogeneous dispersion of PPy along the CNF surface. The incorporation of PPy@CNF significantly improved both mechanical strength and conductivity of the gelatin hydrogel. Meanwhile, the Hofmeister effect induced by (NH₄)₂SO₄ strengthened the hydrogel network, and the introduction of betaine further enhanced its anti-freezing and moisture-retention properties. The optimized GPC hydrogel exhibited a high tensile strength of 1.02 MPa, conductivity of 1.5 S·m^–1, and stable performance at temperatures down to –50 °C. Furthermore, it was successfully assembled into a wearable strain sensor for real-time human motion monitoring, and as an electrode layer in a flexible triboelectric nanogenerator (TENG), enabling biomechanical energy harvesting and self-powered sensing. This work provides a promising strategy for developing sustainable, multifunctional hydrogels for next-generation wearable electronics.

Single-step ethylene polymerization over a binary catalyst, including zirconocene precatalysts of various designs, has been studied to obtain polymer compositions based on ultrahigh-molecular-weight polyethylene (UHMWPE) and low-molecular-weight HDPE (LMWPE) directly in synthesis. Zirconocenes rac-(CH₃)₂SiInd₂ZrCl₂ (Zr-1) and rac-(C₆H₁₀)CpIndZrCl₂ (Zr-2) activated with methylaluminoxane (MAO) were used as the components of the binary catalyst. It has been shown that the use of Zr-1/MAO and Zr-2/MAO in ethylene polymerization at 30 °C leads to the production of UHMWPE with M_w=1000 kg·mol^–1 and LMWPE with M_w=18 kg·mol^–1, respectively. Reactor polymer compositions (RPC) with LMWPE fraction contents ranging from 9 wt% to 42 wt% were obtained when a molar fraction of Zr-2 in the binary catalyst (Zr-1+ Zr-2)/MAO varied in the range from 0.3 to 0.85. A study of the molecular weight characteristics of RPC showed that it has a wide bimodal molecular weight distribution (MWD) and includes UHMWPE (M_w=1000 kg·mol^–1) and LMWPE (M_w=18 kg·mol^–1) fractions. The degree of crystallinity of the polymer products was determined using the DSC method. The tensile properties and melt indices of the materials were studied depending on the LMWPE fraction content in the polymer composition. UHMWPE/LMWPE compositions with high tensile properties and fluidity at a load of 5 kg were obtained.

The use of biomass feedstocks for the manufacture of high-performance polymers can help expand their range of applications and reduce their dependence on finite fossil resources. However, improving the heat resistance and hydrophilicity of bio-based polyesters remains a significant challenge. Herein, we introduce N,N'-trans-1,4-cyclohexane-bis(pyrrolidone-4-methylcarboxylate) (CBPC), a novel bio-based tricyclic dibasic ester synthesized from renewable dimethyl itaconic acid and trans-1,4-cyclohexane diamine via an aza-Michael addition reaction. As a unique comonomer, CBPC features a rigid tricyclic backbone that significantly enhances chain packing and thermal stability, whereas its pyrrolidone side groups impart tunable polarity and improved hydrophilicity. Using CBPC, diphenyl carbonate, and 1,4-butylene glycol, a series of PBCC copolymers with 10 mol%–30 mol% CBPC was synthesized via ester-exchange and melt polycondensation methods. Incorporation of CBPC raised the melting temperature (T_m) from 56.8 °C to 225.8 °C and the initial decomposition temperature (T_d5%) from 258.0 °C to 306.7 °C, positioning PBCC among the most heat-resistant bio-based polyesters reported. Additionally, the pyrrolidone units enabled transformation from hydrophobic to hydrophilic. This study demonstrates that CBPC is an effective and innovative building block for the design of bio-based polymers with enhanced thermal and surface properties, offering a promising strategy for the development of high-performance sustainable materials.

In this study, a novel linear polyimide chain (PTCDA-DCH) was used as an electrochemiluminescence (ECL) emitter, employing a chiral metal-organic framework (MOF) (Zn-Dcam-dabco) as the chiral selector and ferrocene (Fc) as a quencher to construct a chiral sensor for detecting histidine (His) enantiomers. Competitive interactions between Fc and His induce partial Fc desorption from the sensor surface, leading to ECL signal recovery. Differential Fc release due to the distinct binding affinities of Zn-Dcam-dabco for His enantiomers enabled precise chiral discrimination. Notably, the sensor achieved the quantitative detection of His enantiomers with an limits of detection (LOD) of 8 μmol/L. Furthermore, the sensor demonstrated excellent recovery rates of 98.0%–104% for l-histidine (L-His) and 92.0%–95.9% for D-His in spiked milk samples, validating its reliability for real-sample analysis. This study provides a promising platform for ECL-based chiral recognition, bioanalysis, and the rapid assessment of amino acids in food products.

The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting. In this work, an organic luminescent molecule was encapsulated within polyacrylamide microspheres and embedded in a gold nanorod-doped, ferric ion-crosslinked hydrogel exhibiting upper critical solution temperature behavior. The obtained composites exhibited fluorescence, thermally activated delayed fluorescence, and phosphorescence. Through the application of extrusion or uniaxial stretching, the orientation of the gold nanorods was modulated, enabling polarization-dependent luminescence through transverse surface plasmon resonance absorption. At 300% uniaxial strain, the polarized fluorescence intensity difference at 520 nm reached 0.29. Furthermore, ultraviolet irradiation was employed to locally disrupt the orientation of the gold nanorods, resulting in depolarization within the irradiated regions. These areas displayed non-polarized fluorescence, while the non-irradiated regions retained both emission and fluorescence polarization characteristics. Localized imprinting was employed to modulate material thickness, thereby controlling the density of gold nanorods. Thinner regions exhibited weaker transverse localized surface plasmon resonance absorption, while thicker regions showed stronger absorption, enabling the coexistence of blue–green fluorescence and polarization patterns. Local humidification effectively reduced phosphorescence intensity, enhancing the material’s environmental responsiveness. The composite demonstrated excellent reversibility over multiple stretching–self-healing cycles and pattern-switching processes, highlighting its strong potential for multidimensional optical encryption and intelligent anti-counterfeiting applications.

Understanding the thermodynamic behavior of complex fluids in confined environments is critical for various industrial and natural processes including but not limited to polymer flooding enhanced oil recovery (EOR). In this work, we develop Atif-V2.0, an extended classical density functional theory (cDFT) framework that integrates the interfacial statistical associating fluid theory (iSAFT) to model multicomponent associating fluids composed of water-soluble polymers, alkanes, and water. Building on the original theoretical framework of Atif for modeling nanoconfined inhomogeneous fluids, Atif-V2.0 embeds explicit solvent and captures additional physical interactions - hydrogen bonding, which are critical in associating fluid systems. The other key feature of Atif-V2.0 is its ability to account for polymer topology. We demonstrate its capability by predicting the equilibrium structure and thermodynamic behavior of branched hydrolyzed polyacrylamide solutions near hard walls with various branching topologies, which provides a robust theoretical tool for the rational design of EOR polymers.

Knotting occurs in polymers and affects polymer properties. Physical understanding of polymer knots is limited due to the complex conformational space of knotted structures. The knotting problem can be handled by the tube model, which assumes that knotted polymer segments are confined in a virtual tube. Recently, we quantified this virtual tube using a computational algorithm. The algorithm was limited to the simplest knot: 3₁ knot. It remains unclear how the tube model and computational algorithm are applied to more complex knots. In this work, we apply the tube model to 4₁, 5₁, and 5₂ knots, resulting in several findings. First, the computational algorithm developed for 3₁ knot cannot be directly applied to 4₁ knot. After modifying the algorithm, we quantify the tubes for 4₁ knot. Second, we find that, for all four knot types, the knot-core region have less average bending energy density than unknotted regions when the chain bending stiffness is small. This counterintuitive result is explained by the tube model. Third, for all four knot types, polymer segments at the boundaries of knot cores adopt nearly straight conformations (almost zero bending) and exhibit lower local bending compared to other knot-core regions and unknotting regions. This local behavior is also consistent with prediction from the tube model. This counterintuitive result is also explained by the tube model. Fourth, for all four knot types, when a polymer has non-uniform bending stiffness, a knot prefers certain chain positions such that the knot boundary locates at one stiff segment. Overall, our work paves the way for applying the tube model to complex polymer knots and obtains many common results for different knot types, which can be useful in understanding many knotting systems, such as DNA knots in vivo.

Shear banding in entangled polymer melts remains a fundamental yet unresolved phenomenon in nonlinear polymer rheology. Here, we perform molecular dynamics simulations of bidisperse entangled melts—comprising equal numbers of chains with lengths N=200 and N=400—to uncover the structural origins and dynamic evolution of shear banding. This bidisperse system amplifies spatial heterogeneities in the entanglement network and facilitates direct comparison with monodisperse melts of N=300, revealing quantitatively consistent steady-state shear stress versus shear rate responses. Notably, a pronounced stress plateau spanning over an order of magnitude in shear rate is observed, within which shear banding emerges reproducibly across independent simulations, as confirmed by systematic velocity profile and interface position analyses. Our findings challenge the prevailing notion that shear banding arises solely from dynamic flow instabilities. Instead, we establish a microstructure-driven framework, demonstrating that shear band nucleation is governed by pre-existing structural heterogeneities—specifically, localized weakening of the entanglement network at short-chain-enriched “soft spots”, indicative of a robust microstructural memory effect. During shear start-up, short chains preferentially disentangle and migrate along the shear direction; beyond a critical strain, long chains retract and redistribute away from the fast shear band center to minimize elastic energy. This chain-length-dependent migration dynamically enriches the shear band in short chains, stabilizing its structure and revealing a molecular mechanism that links entanglement heterogeneity to macroscopic flow localization. By bridging molecular-scale structural features with nonlinear rheological responses, this work offers a complementary perspective to classical tube and convective constraint release (CCR) models, highlighting the critical interplay between microstructural heterogeneity and chain migration in the onset and persistence of shear banding.

The chain conformation of polymers in binary solvent mixtures is a key issue in the study of functional soft matter and lies at the heart of various applications such as smart soft materials. Based on a minimal lattice model, we employ Monte Carlo (MC) simulation to systematically investigate the effects of solvent qualities on the conformation of a single homopolymer chain in binary mixed solvents. We also perform calculations using a Flory-type mean-field theory. We focus on how the introduction of a second solvent B affects the dependence of chain conformation on the quality of solvent A. We mainly examine the effects of the composition of solvent B, denoted by x, and the interactions between the two solvents. First, when x is low, the mean-square chain radius of gyration exhibits qualitatively similar behaviors to those in an individual solvent A, with a slight chain contraction when solvent A is very good. Second, in equal-molar mixtures with x=0.5, a homopolymer chain collapses when solvent A is either poor or very good, while expands at intermediate qualities. Lastly, at large x, a chain undergoes a coil-to-globule transition with the increasing quality of solvent A when solvent B is good, but mainly adopts the collapsed conformation when solvent B is poor. Our findings not only improve our understanding on the chain conformation in binary solvent mixtures, but also provide valuable guidance on the rational design of stimuli-responsive polymeric materials.

To address the poor mechanical properties of polydimethylsiloxane (PDMS) and enhance the understanding of the reinforcement mechanisms of aerogel network structures in rubber matrices, this study reinforced PDMS using an ordered interconnected three-dimensional montmorillonite (MMT) aerogel network. The average pore diameter of the aerogels was successfully reduced from 11.53 μm to 2.51 μm by adjusting the ratio of poly(vinyl alcohol) (PVA) to MMT via directional freezing. Changes in the aerogel network were observed in field emission scanning electron microscope (FESEM) images. After vacuum impregnation, the aerogel network structure of the composites was observed using FESEM. Tensile tests indicated that as the pore diameter decreased, the elongation at break of the composites first increased to a peak of 329.61% before decreasing, while the tensile strength and Young's modulus continuously increased to their maximum values of 6.29 MPa and 24.67 MPa, respectively. Meanwhile, FESEM images of the tensile cracks and fracture surfaces showed that with a reduction in aerogel pore diameter, the degrees of crack deflection and interfacial debonding increased, presenting a rougher fracture surface. These phenomena enable the composites to dissipate substantial energy during tension, thus effectively improving the mechanical strength of the composites. The present work elucidates the bearing of ordered three-dimensional aerogel network structures on the performance of rubber matrices and provides crucial theoretical insights and technical guidance for the creation and optimization of high-performance PDMS-based composites.