Snow and freezing disasters are recurrent weather and climate phenomena that affect the world annually. These events exert a significant influence on numerous aspects of life, including transportation, power supply, and daily activities, and result in considerable economic losses. This study aims to provide a comprehensive analysis of the regions affected by these disasters, the preventive and responsive measures employed, recent advancements in key materials, and the challenges encountered. By doing so, we can gain a deeper understanding of the vital role, significant advantages, and untapped potential of key materials for effectively preventing and responding to snow and freezing disasters. Furthermore, promoting research and utilization of these materials not only contributes to the development of the safety and emergency equipment industry but also strengthens the supply of advanced and suitable safety and emergency equipment.

Polymeric materials which can undergo controlled degradation and recycling are of great significance for a sustainable society. Although tremendous progress has been made in the degradation and recycling of both thermoplastic and thermoset plastics, the development of high-performance degradable polymer adhesives is rare. Here, we have prepared high-performance nucleobase-containing thioctic acid-based supramolecular polymer adhesives through free radical polymerization. The specific hydrogen-bonding interactions between complementary nucleobases greatly improve the weak cohesion of the thioctic acid-based polymers and enhance the environmental stability of the thioctic acid-based polymers simultaneously. Degradation of the nucleobase-containing thioctic acid-based supramolecular polymers is achieved by the reduction of the disulfide backbone, and the cycle of degradation and repolymerization is further achieved via oxidative polymerization. The adhesion strength of the nucleobase-containing thioctic acid-based supramolecular polymers after two cycles of degradation and repolymerization still reaches as high as 4.7±0.3 MPa. This work provides an approach for the development of environmentally stable and high-performance degradable thioctic acid-based adhesives.

Amyloid-like proteins are critical for interfacial adhesion across various marine organisms and bacteria. However, the specific contributions of different functional residues remain unclear. Herein, we introduce an approach to deconstruct and mimic these residues using synthetic homopolymers and random copolymers with phenyl, amino, carboxyl, and hydroxyl functional groups using reversible addition-fragmentation chain transfer (RAFT) polymerization. The resulting polymers, designed with comparable molecular weights (M_n: 10–20 kDa) and narrow dispersities (PDI<1.3), mimic the diverse surface chemistry of amyloid-like proteins, enabling systematic investigation of their adhesive properties. The interfacial adhesion forces of different polymer films were quantified using atomic force microscopy (AFM) with a colloidal probe. Remarkably, copolymers with multiple functional groups demonstrated significantly enhanced adhesion compared to homopolymers, a trend corroborated by macroscopic shear strength and stability tests. These results highlight that the synergistic effects of multiple functional groups are crucial for achieving universal interfacial adhesion of macromolecules, offering insights into protein adhesion mechanisms, and guiding polymer-based interfacial modifications.

A high humidity-resistant, dual mechanical responsive, and reversible mechanochromic wrinkling system based on a VHB 4910-polydimethylsiloxane (PDMS) substrate with a thin film consisting of 90 wt% poly(vinyl butyral) (PVB) and 10 wt% hydroxypropyl cellulose (HPC) has been reported. The wrinkling system exhibited significant optical tuning from transparent to opaque states with 50% changes in transmittance, which was achieved through the dual mechanical modes of pre-stretching and releasing processes or bending. Upon exposure to ethanol vapor or a re-flattening process, wrinkles can be erased, yielding a transparent state. Consequently, the wrinkling system could be reversibly switched between transparency and opacity for 1000 cycles with marginal changes in the optical performance. Owing to the insolubility of PVB in water, the wrinkling patterns exhibited excellent durability in high-humidity environments (relative humidity (RH) = 99%). Furthermore, the smart encryption device is also demonstrated via mechano-controlled surface topography by patterning the wrinkling system, suggesting potential applications of the designed structure in smart windows, anti-counterfeiting, dynamic display, optical information encryption, and rewritable surfaces.

Functional materials synthesized from bio-based building blocks are fascinating and challenging in the fields of chemistry and materials science. Herein, we present a versatile strategy for synthesizing bio-based stimulus-responsive polymers derived from itaconic acid (IA). Bearing an azobenzene-containing side chain, the IA-based epoxy polymer exhibited both photoresponsiveness and acid/base-stimulus responsiveness. With controllable manipulation of the stress field of the wrinkling IA-polymer film via the stress relaxation effect resulting from the reversible cis-trans isomerization of the azobenzene moieties or solvent-induced swelling of the film, various tailor-made patterned wrinkling surfaces were conveniently fabricated. More importantly, the azobenzene protonation/deprotonation yields a reversible visual color transformation between pale yellow and purple in the film, which allows these IA-based polymer-coated surfaces to be utilized as rewritable information storage media. Various elegant pattern information can be acid-printed and base-erased (within 10 s) for multiple cycles and legible for over one day under laboratory conditions. Notably, the aforementioned dual-stimulus responsiveness of the IA-based polymer film enables its surface to be applied in information encryption. This study not only paves a new avenue for the convenient fabrication of stimulus-responsive surfaces but also sheds light on the development of functional polymers through green engineering.

Sizing treatment is a suitable technique to modify the fiber-matrix interfaces without damage of inherent performance of fibers. In this work, sizing agents based on Janus particles (JPs) were utilized to enhance the interface of basalt fiber (BF)/poly(vinyl chloride) (PVC) composites. polystyrene/poly(butyl acrylate) (PS/PBA)@silica JPs were synthesized by seed emulsion polymerization and three different sizing agents were prepared for BF sizing treatment. JPs with organic soft sphere and inorganic hard hemisphere enhanced the interfaces through their amphiphilicity, chemical bonding and mechanical interlock. The mechanical properties of composite with JPs sizing treated BFs performed better when there was one JPs layer modified on the interface. According to the intermitting bonding and gradient modulus theory, JPs patterned interfaces are ideal transition layers between high modulus BF and low modulus PVC.

Endowing stimuli-responsive materials with micro-nano structures is an intriguing strategy for the fabrication of superwetting surfaces; however, its application is limited by poor chemical/mechanical stability. Herein, a simple and versatile strategy was developed to fabricate durable polymeric superwetting surfaces with photoswitchable wettability on hierarchically structured metallic substrates. Inspired by nature, a novel functional terpolymer incorporating mussel-inspired catechol groups, photoresponsive azobenzene groups, and low-surface-energy fluorine-containing groups was synthesized via solution radical polymerization. The azobenzene-containing terpolymer possesses outstanding photoresponsiveness in both the solution and film states because of the trans-cis isomerization of the azobenzene moieties. After dip-coating with the mussel-inspired azo-copolymer, the as-prepared smart surfaces exhibited a photo-triggered change in wettability between high hydrophobicity and superhydrophilicity. More importantly, these superwetting surfaces with enhanced adhesion properties can tolerate harsh environmental conditions and repeated abrasion tests, thereby demonstrating excellent chemical robustness and mechanical durability. This study paves a new avenue for the convenient and large-scale fabrication of robust smart surfaces that could find widespread potential applications in microfluidic devices, water treatment, and functional coatings.

High-voltage LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) cathodes are critical for enhancing the energy density of lithium-ion batteries (LIBs). The development of binders compatible with high-voltage NCM811 cathode materials is crucial to enhance the electrochemical performance of LIBs. However, the traditional fluoropolymer binder, poly(vinylidene difluoride) (PVDF), can potentially leach components or break down into poly(fluoroalkyl substances) (PFAS) chemicals, thereby contributing to PFAS contamination. A novel fluorine-free polymer, polysulfone-polyamide-polyimide (SPIO), was designed and synthesized as a binder for NCM811 cathodes. The SPIO binder exhibits exceptional mechanical properties and superior electrochemical characteristics. The cathode film fabricated with SPIO demonstrated a remarkable delamination force of 8 N (390 N·m^–1), indicating robust adhesion. The Li||NCM811 cell incorporating the SPIO binder retained 80% of its initial capacity after 300 cycles at a current density of 0.2 C. In comparison, the control cells assembled with the PVDF binder retained only 52% of their capacities under the same cycling conditions. Furthermore, the SPIO binder exhibited improved compatibility with the electrolyte. Transmission electron microscopy analysis of the cathode films after 100 cycles revealed the formation of a uniform, dense, and continuous chemical-electrochemical interface (CEI) by the SPIO binder on the surface of the NCM811 particles, which significantly contributed to the enhancement of the electrochemical performance. These results highlight the potential of SPIO as an advanced binder material for high-performance lithium-ion batteries.

Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios. However, current regulating strategies focus on the construction process of individual sensors, the response performance of the as-formed sensors is still hard to autonomously tune with external stimulus changes like human skin. Here, we propose a new strategy that realizes post-tuning of the sensing performance by introducing a temperature-dependent phase transition elastomer into the sensing film. Through an interfacially confined photopolymerization reaction, a graphene-based phase-transition elastomeric (GPTE) film with a robust interface and excellent conductivity is well-formed at the water/air interface. Benefiting from the crystallization-melt dynamic switching in the elastomer network, the GPTE film could experience the reversible transformation between soft (1.65 MPa) and stiff (12.27 MPa) states, showing huge changes of elastic modulus up to seven times near the phase transition temperature (28.5 °C). Furthermore, the GPTE film is designed into a suspended perceptual configuration realizing the dynamic detection of 3D deformation adapted to temperature changes with up to 3.5-fold difference in response sensitivity. Finally, the self-adaptive sensing behavior of temperature-mediated 3D deformation is demonstrated by the effective detection of the dynamic stimulation process of cold and hot water droplets by the GPTE suspended film. The proposed strategy of phase transition-induced post-tuning of sensing performance could greatly facilitate flexible mechanical sensors towards a more intelligent one.

Polymer adsorption at solid interfaces plays an important role in the dynamics of nanoscale polymer films. We investigated the influence of the interfacial chain adsorption on the glass transition temperature (T_g) and dewetting of polystyrene (PS) thin films on a graphene substrate that has strong interaction with PS. We found that the T_gs of PS films show a non-monotonic trend with increasing amount of polymer adsorption at the interface—first increasing and then decreasing, and this change in T_g is accompanied by a wetting-dewetting transition of the PS films. Film morphological analysis showed that the PS films dewet from the interfacially adsorbed layers rather than from the substrate, i.e., autophobic dewetting, indicating the presence of an unfavorable interaction between the adsorbed and free PS chains. We ascribed the repulsive interaction to the formation of a dense adsorbed layer on graphene due to the π-π interaction between PS and graphene, which prevents the non-adsorbed PS chain from penetrating into the adsorbed layer. This may lead to drops in T_g at high adsorption extent.

The dynamics of the drying process of polymer solutions are important for the development of coatings and films. In the present work, digital holographic microscopy (DHM) was performed to capture the drying dynamics of poly(ethylene oxide) (PEO) droplets using a gold nanoparticle tracer, where the heterogeneous flow field in different regions was illustrated. This demonstrates that the gold nanoparticles at either the center or the edge regions of the droplet exhibit anisotropic kinematic behavior. At early stage, Marangoni backflow causes gold nanoparticles to move towards the edge firstly, and the circles back towards the droplet center after arriving the contact line with a sudden increase in z axis for 10.4 μm, indicating the scale of the upward-moving microscopic flow vortices. This phenomenon does not occur in water droplets in the absence of polymers. The gold nanoparticles underwent Brownian-like motion at the center of the PEO droplet or water droplet owing to the low perturbation of the flow field. At the late stage of pinning of the PEO droplets, the motion showed multiple reverses in the direction of the gold nanoparticles, indicating the complexity of the flow field. This study enhances the understanding of the drying dynamics of polymer solution droplets and offers valuable insights into the fabrication of surface materials.

Mechanochromic polyolefins represent a novel class of functionalized polyolefins, which still remains significant challenges. Pd(II)-catalyzed coordination-insertion copolymerization is a feasible method for achieving this kind of polymers, yet with linear microstructures. Ring-opening metathesis polymerization (ROMP) offers another promising avenue for affording functionalized polyolefins. This method exhibits high polar group tolerance and the ability to precisely regulate polymer branches. In this study, we report the method for producing mechanochromic branched polyethylenes via ROMP. By employing the terpolymerization of a well-designed monomer containing the mechanochromic group, NB-ABF, with cyclooctene (COE) and long-chain 5-hexylcyclooctene (COE-C6), following by hydrogenation process, we synthesized a range of functionalized branched polyethylenes characterized by varied branching density and polar monomer incorporation. These polymers bear a structural resemblance to functionalized ethylene-octene copolymers. After crosslinking, mechanochromophores are generated, and mechanochromism is achieved in uniaxial tensile testing. A comprehensive assessment reveals that both the incorporation of polar monomers and variations in branching density significantly influence their mechanical properties. Notably, upon stretching, these materials display pronounced visible color change, confirming the successful development of mechanochromic branched polyethylenes.

Natural rubber (NR) is a crucial elastic material used for damping and sealing applications in the nuclear industry, but its mechanical stability under radiation remains inadequate. Current efforts to improve radiation resistance rely on the addition of antiradiation agents, however, the effects of the components and microstructures of NR itself on radiation resistance remain unclear. In this study, we compared the composition and structure differences of four typical commercially used NR materials and investigated their effects on gamma radiation resistance. Furthermore, we examined the impact of non-rubber components (NRC) in NR on radiation resistance using deproteinized and dephosphorylated NR model samples. Our results revealed that NRC, such as proteins and phospholipids can enhance the strength of natural rubber before radiation exposure. However, after the removal of NRC, the samples exhibited improved mechanical stability under irradiation. Additionally, the ash content in NR could also influence the radiation resistance, as metal ions may react with the active centers produced by radiation, thereby enhancing the radiation resistance of the rubber. This work identifies the effect of non-rubber components in NR on radiation resistance and may serve as a reference for screening and developing radiation-resistant NR materials.

Dimethyl sulfoxide (DMSO) possessing strong solvency and high boiling point is a very important aprotic polar solvent in organic and polymer synthesis. Notably, it is also a useful synthon in organic chemistry. However, the direct incorporation of DMSO in polymer synthesis remains challenging. In this work, DMSO was successfully converted to nitrogen-containing heterocyclic polymers as a monomer via multicomponent polymerizations (MCPs) with dialdehydes and diamines in the presence of K₂S₂O₈/t-BuOK at 120 °C in 6 h. A series of poly(phenylquinoline)s with high M_w values (up to 5.11×10⁴) were obtained in satisfactory yields (up to 82%), performing good solubility, good thermal and morphological stability as well as excellent film-forming ability. The thin films of poly(phenylquinoline)s exhibit high refractive index value in a wide wavelength range of 400–1700 nm. Thus, this work not only enriches the family of MCPs but also provides an efficient strategy for the conversion of DMSO into functional polymeric materials that are potentially applicable in diverse areas.

Flexible polymer-based foam sensors have significant potential for application in wearable electronics and motion monitoring. However, these prospects are hindered by the complex and unenvironmentally friendly manufacturing processes. In this study, we employed melt blending and supercritical carbon dioxide foaming to fabricate an ethylene-vinyl acetate copolymer (EVA)/low-density polyethylene (LDPE)/carbon nanotube (CNT) piezoresistive foam sensor. The cross-linking agent bis(tert-butyldioxyisopropyl) benzene and the conductive filler CNT were incorporated into the EVA/LDPE composite, successfully achieving a chemically cross-linked and physically entangled composite structure that significantly enhanced the storage modulus and complex viscosity. Additionally, the compressive strength of EVA/LDPE/CNT foam with 10 parts per hundred rubber (phr) CNT reached 1.37 MPa at 50% compression, marking a 340% increase compared to the 0.31 MPa of the CNT-free sample. Furthermore, the EVA/LDPE/CNT composite foams, which incorporated 10 phr CNT, were prepared under specific foaming conditions, resulting in an ultra-low density of 0.11 g/cm³ and a higher sensitivity, with a gauge factor of –2.3. The piezoresistive foam sensors developed in this work could accurately detect human motion, thereby expanding their applications in the field of piezoresistive foam sensors and providing an effective strategy for the advancement of high-performance piezoresistive foam sensors.

Modified polyimides (MPIs) possess excellent thermal stability, chemical stability, and mechanical properties, and are considered to be a kind of dielectric material for high-frequency communication. Enhancing the rigidity of the polymer chains and intermolecular interactions can ensure low D_k/D_f at high frequency, which is attributed to the effective restriction of dipole orientations. However, it is difficult to achieve tight chain packing in an overly rigid polymer chain, whereas an overly flexible polymer chain might be insufficient to restrain small-scale molecular motions below T_g. To balance the trade-off between the rigidity of the polymer chains and tight chain packing, MPI was developed with a rigid-soft structure based on a naphthalene-alkyl-based diamine. On the one hand, incorporating the soft unit can enhance the movability of polymer chains to achieve dense chain packing for polyimides (PIs). On the other hand, the presence of rigid aromatic units can enhance intermolecular interactions and further restrict the motion of polar imide groups below T_g. As a result, the resultant MPI can prevent small-scale molecular motion below T_g. In contrast to the reference PI-TFMB-6FDA, D_k/D_f is significantly reduced from 2.72/0.0075 to 2.73/0.005 at a high frequency of 10 GHz. Furthermore, the rigid-soft structure endows PIs with good thermoplasticity owing to the good chain flexibility above T_g. In addition, PIs based on rigid-soft structures can preserve favorable thermal stability.

Poly(_L-lactide) (PLLA), a leading biodegradable polyester, has demonstrated potential as a sustainable alternative, owing to its excellent biodegradability and rigidity. However, their slow crystallization kinetics and poor heat resistance limit their application scope. Recent advances have highlighted that the combination of extensional flow and thermal fields can achieve toughness–stiffness balance, high transparency, and good heat resistance. However, the effect of extensional flow on the post-non-isothermal crystallization of PLLA during heating and the resulting crystalline texture remains unclear. In this study, PLLA with a heterogeneous amorphous structure and oriented polymorph was prepared by extensional flow. The effect of heterogeneous amorphous structures on non-isothermal crystallization kinetics during the heating process was studied by thermal analysis, polarized optical microscopy, infrared spectroscopy, and ex situ/in situ X-ray characterization. These results clearly illustrate that extensional flow enhances the formation of oriented crystalline structures, accelerates non-isothermal crystallization, and modulates the polymorphic composition of PLLA. Moreover, an unexpected dual cold-crystallization behavior is identified in ordered PLLA samples upon extensional flow, which is from the extensional flow-induced heterogeneous amorphous phase into α' phase (low-temperature peak) and the pristine amorphous phase into α phase (high-temperature peak). The extensional flow primarily promotes the formation of the more perfect α and α' phases, but has a negative effect on the final content of α phase formed after cold crystallization and α'-to-α phase transformation. The findings of this work advance the understanding of PLLA non-isothermal crystallization after extensional flow and offer valuable guidance for high-performance PLLA upon heat treatment in practical processing.

The performance of polymer networks is directly determined by their structure. Understanding the network structure offers insights into optimizing material performance, such as elasticity, toughness, and swelling behavior. Herein, in this study we introduce the Dijkstra algorithm from graph theory to characterize polymer networks based on star-shaped multi-armed precursors by employing coarse-grained molecular dynamics simulations coupled with stochastic reaction model. Our research focuses on the structure characteristics of the generated networks, including the number and size of loops, as well as network dispersity characterized by loops. Tracking the number of loops during network generation allows for the identification of the gel point. The size distribution of loops in the network is primarily related to the functionality of the precursors, and the system with fewer precursor arms exhibiting larger average loop sizes. Strain-stress curves indicate that materials with identical functionality and precursor arm lengths generally exhibit superior performance. This method of characterizing network structures helps to refine microscopic structural analysis and contributes to the enhancement and optimization of material properties.

This study explores the molecular design of sulfur-containing polymers with high refractive indices (RI) and optimized Abbe numbers for advanced optical applications. The high molar refraction and low dispersion of sulfur make it an ideal component for enhancing the optical properties of polymers. Density functional theory (DFT) calculations were employed to predict the RI and Abbe numbers for a range of sulfur-based polymers. To improve the accuracy of the theoretical predictions, a correction function was developed by comparing the calculated values with experimental data. The key polymer families investigated included sulfur-containing polycarbonates, heterocyclic optical resins, and cycloolefins, all modified to balance RI enhancement with dispersion control. The results demonstrate that increasing the sulfur content and introducing specific heterocycles and bridged rings can effectively increase the RI while maintaining desirable Abbe numbers. Polymers incorporating 1,4-dithiane and sulfur-bridged rings exhibit excellent optical clarity and minimal visible light absorption, making them suitable for lens and coating applications. The study also calculated the UV-visible spectra for the most promising polymers, confirming their high transparency. This work establishes a predictive framework for developing high-performance optical polymers and offers a systematic approach for balancing the refractive index and dispersion, thereby providing valuable insights for the design of next-generation optical materials.