Polyvinyl chloride (PVC) is extensively employed as a cable material in the electric power and construction sectors owing to its affordability and ease of processing. Nonetheless, its susceptibility to ultraviolet (UV) radiation during long-term outdoor use leads to pronounced aging and material degradation. In this work, carbon quantum dots (PCDs), notable for their robust UV absorption and chemical stability, were synthesized via a one-step hydrothermal method, yielding particles with UV absorption center wavelength around 365 nm. These PCDs were first dispersed within a liquid plasticizer to ensure homogeneous distribution before their incorporation into the PVC matrix. Accelerated UV aging tests revealed that PVC composites containing 3% PCDs exhibited remarkable retention in both tensile strength and elongation at break corresponding to 98.6% and 95.6%, respectively-representing significant enhancements compared to unmodified PVC. Surface analyses using scanning electron microscopy (SEM) confirmed a marked reduction in surface cracking upon the addition of PCDs, while Fourier transform infrared spectroscopy (FTIR) demonstrated that this approach effectively inhibits the formation of C=C bonds, thus mitigating free radical-induced degradation. Collectively, these findings validate the proposed anti-aging mechanism of PCDs in PVC. This work introduces a novel approach for utilizing carbon dots as eco-friendly UV absorbers and dispersing carbon dots in soft PVC products without the help of solvent, and provides a practical strategy for enhancing the service life of PVC-based materials under UV exposure.

In recent years， capacitors have become widely utilized as core components in modern electrical equipment and electronic facilities， due to advancements in electric power systems， communication， and the electronic industry. However， film capacitors cannot meet the demand for future device miniaturization due to limitations in energy storage density and temperature resistance. Therefore， the advancement of dielectric materials with high energy storage density is crucial for achieving compact and lightweight dielectric capacitors in the future. This review offers a succinct summary of the research progress in polymer-based film capacitor dielectric materials. It begins by discussing the energy storage materials used in polymer-based film capacitors， including their structural properties， dielectric properties， and energy storage mechanisms. The study focuses on various dielectric materials， such as polypropylene-based， polyimide-based， polyvinylidene fluoride， polystyrene-based， and polytetrafluoroethylene-based. It also includes an analysis and summary of the advantages and disadvantages of each material，which includes the improvement of its energy storage density， the regulation of its temperature resistance， and the optimization of its preparation process. Finally， in view of some existing shortcomings and deficiencies of the current polymer-based film capacitor energy storage materials， the development direction of polymer-based dielectric materials is prospectively discussed.

This study presents an innovative undergraduate experiment that integrates the preparation and sensing application of conductive hydrogels to explore hydrogen bonding. By constructing a poly(vinyl alcohol)/polyethylene glycol/phytic acid (PVA/PEG/PA) conductive hydrogel system, the mechanism and application of hydrogen bonding are made observable through thermoplastic behavior and human motion sensing. Using a one-step sol-gel method, PVA/PEG/PA hydrogels are prepared with component ratios adjusted to influence mechanical properties and thermoplasticity. Practice sessions, like circuit conductivity verification and human motion signal collection, transform the abstract theory of hydrogen bonding into a multisensory learning experience and address the limitations of traditional lecture-heavy methods which often struggle to demonstrate the practical impact of molecular-level interactions. This integration of synthesis, characterization, and application significantly enhances educational effectiveness and cultivates problem-solving skills through a hands-on investigation. This teaching model offers an integrated approach for polymer physicochemistry courses, cultivating engineering thinking and scientific inquiry abilities.

The inherent brittleness of polylactic acid (PLA) restricts expand its functional applications. This study innovatively constructs a sustainable multilayer composite PLA-based foam featuring a "soft-hard" layer interface. The high-toughness polypropylene carbonate (PPC) was employed into the PLA matrix to regulate macromolecular chain mobility and form new covalent bonds, successfully reducing crystallinity from 50.87% to 20.94%. The 30 wt% PPC/PLA composite foam with optimized the melt index achieved 4.52 × 106 cells/cm3 of high cell density and uniform cell structure by the supercritical carbon dioxide foaming technology. Furthermore, a "chemical interlocking" mechanism was established via covalent and hydrogen bonding between the "soft" (PPC/PLA) and "hard" (PLA) layers by employing bio-derived cardanol as an interfacial compatibilizer. This engineered interface for "soft- hard" layer interface boasts a bonding strength of 9.73 MPa, effectively broadens stress transmission pathways and promotes acoustic energy dissipation. Consequently, the multilayer composite foam exhibited a 13% enhancement in compressive strength and achieved a superior low-frequency sound transmission loss of 39 dB compared to corresponding single-layer sample. This research offers a robust theoretical reference for designing high-performance of fully biodegradable functional foams.

Traditionally, high electromagnetic interference (EMI) shielding materials prioritize high conductivity via heavy filler loading, often causing short circuits and overheating problems in highly integrated electronic devices. To address this, conductive hollow glass microspheres@Ag@Polydopamin (HAP) were employed as polar plates, dispersing uniformly in an isolated state within in an insulating organosilicone (OSi) matrix that acts as the dielectric layer to construct a micro-capacitor model. The resulting induced currents, ingeniously driven by electron oscillation, enhance interface polarization and conductance loss. Consequently, the HAP/OSi composite achieves a remarkable EMI shielding effectiveness (SE) of 45 dB at an ultra-low conductivity of 0.0435 S/m and 8 wt.% loading. Furthermore, integrating polyimide/CNT-COOH@Ag (PCA) aerogel onto the upper and lower surfaces of the HAP/OSi composite forms a sandwich structural PCA-HAP/OSi-PCA composite, elevating EMI SE to a superior 60 dB at the extremely low 0.0501 S/m conductivity. This is attributed to the synergistic effects of enhanced interlayer polarization and multiple reflections within the micro-capacitance network. In addition, the PCA-HGMs@Ag@PDA/OSi-PCA composites also exhibit excellent thermal conductivity, thermal mechanical stability across an ultra-wide temperature range, and sound insulation. This multifunctional design effectively addresses EMI, heat accumulation, and acoustic pollution, providing comprehensive protection and broadening its application in extreme environments.

Polydimethylsiloxane (PDMS) is an important thermal interface materials in electronic packaging industry with the aid of incorporating thermal conductive fillers. However, the thermal conductivity of PDMS composites is easily affected by outside thermal aging or force field. Herein, hybrid fillers containing boron nitride (BN) and silicon carbide (SiC) or silicon carbide nanowires (SiCNW) were used to construct stable thermal conductive pathways in PDMS matrix under cyclic compression or thermal-oxidative aging conditions. The optimum weight ratio of BN to SiC or SiCNW is 9:1 to obtain high thermal conductivity in PDMS. The thermal conductivity of BN9/SiC1/PDMS and BN9/SiCNW1/PDMS composites are slightly decreased by 4.50 and 4.20%, respectively after 64 h of thermal-oxidative aging when the mass ratio of BN to SiC or SiCNW is 9:1. Higher load bearing capacity of BN9/SiCNW1/PDMS composite can guarantee the good stability of thermal conductivity under cyclic compression. The thermal conductivity of BN9/SiCNW1/PDMS composite material is increased from 0.96 to 1.12 W m- 1 K-1, with a growth rate of 16.60% after 30 cycles of 1000 N compression, while the thermal conductivity of the BN/PDMS composite is decreased under the same compression conditions. Mechanisms of the cyclic compression effect on the variation of structure and thermal conductivity were proposed. This indicates that BN and SiC hybrid filled polymer composites could maintain high thermal conductivity under thermaloxidative aging or cyclic compression.

With the acceleration of industrialization and urbanization, noise pollution has become one of the major environmental issues in public worldwide. Polymer materials have advantages of lightweight, high damping performance, and good processability. They show large application potential in acoustics field. In this work, the mechanisms of acoustic materials were introduced. The structural design methods of different polymer sound absorption materials and polymer sound insulation materials were discussed and systemically compared. Based on the limitations of existing material properties, the preparation methods of polymer composite soundproofing materials and the technologies to improve the noise reduction performance were summarized in detail. In addition, the structural design strategies of multilayer composite acoustic materials, environmentally friendly composite noise reduction materials, and acoustic metamaterials were also proposed, which would provide experiences for fabricating novel noise reduction polymer materials. Finally, the review concluded with the developed perspectives and outlooks of high noise reduction composite materials.

Aerogels transform the evolution of wearable flexible pressure sensors owing to the characteristics of ultralight and ultra-flexible. Depending on the design of pore structure and the construction of conductive network, the key performances such as robustness, sensitivity and detection range of aerogel pressure sensors were improved significantly, broadening their application area. This review highlights the critical influences of pore structure on the sensors and analyzes the formation mechanism and control strategy of micro-pore structure, including honeycomb pore structure, layered pore structure, spider network pore structure, and some other pore structures. The representative conductive raw materials and relevant construction methods of the conductive network in aerogels are investigated for enhancing the sensitivity, including carbon-based materials, MXene materials, and conducting polymer materials. The multi-functional features of the sensors are revealed in the exploration of concrete applications, including human motion monitoring, medical health monitoring, artificial intelligence sensing, and other application areas. By summarizing the recent progress in microstructure regulation and application, this review affords significant insights into the microstructure establishment of aerogels for application in sensors, benefiting the rapid development of wearable flexible pressure sensors.

The employment of acoustic insulation materials is a common strategy widely utilized in noise reduction. Herein, the sound insulation performance of polyvinyl chloride (PVC) was remarkably enhanced by incorporating hexagonal boron nitride (h-BN) subjected to carboxymethyl cellulose sodium (CMC-Na) assisted ball milling, coupled with the addition of polymethyl methacrylate (PMMA). The exfoliation and functionalization of h-BN was successfully realized, and the resultant functionalized boron nitride nanosheets (BN-CMC) was obtained. Subsequently, BN-CMC was introduced and orientated in a mixed matrix of PVC and PMMA through spin-coating technique. The BN-CMC/PMMA/PVC composites exhibited high acoustic insulation and thermal performance by means of the dual reinforcing effect of both organic PMMA and inorganic BN-CMC. The BN-CMC/PMMA/PVC composites with 30 % mass fraction of BN-CMC achieved an average sound transmission loss (STL) of 35.67 dB with the thickness of 0.7 mm, which was 81.5 % higher than that of neat PVC (19.65 dB). This reinforcing effect in sound insulation had exceeded many reported polymer materials by taking consideration of the low thickness. Moreover, less content of orientated BN-CMC (14 wt%) can be used to achieve the reinforcing effect of STL for laminated PVC composites compared with these PVC composites with 30 wt% unfunctionalized h-BN. Furthermore, the mechanisms of sound insulation reinforcement for PVC were analyzed by using dynamic mechanical analysis and scanning electron microscope (SEM) observation. This work presents a facile fabricating approach for lightweight materials with high sound insulating performance in construction and building area.

The escalating thermal challenges posed by increasing power densities in electronic devices emerge as a critical barrier to maintain their sustained and reliable operation. Addressing this issue requires the strategic development of materials with superior thermal conductivity properties to facilitate progress in high-power electronics development. Thermal conductive polymer composites by incorporating ceramic material renowned for their exceptional thermal conductivity adjustability, insulating properties, and moldability, are emerging as a promising solution to this urgent challenge. Hexagonal boron nitride (h-BN) nanomaterials emerge as highly promising candidates for thermal management applications, owing to their exceptional mechanical properties, superior thermal stability, remarkable thermal conductivity coefficients, minimal thermal expansion characteristics, and outstanding chemical inertness. In this work, the progress of ≈10 years on high thermal conductive boron nitride-filled polymer composites is thoroughly summarized. Moreover, strategies for h-BN and other boron nitride nanomaterials-filled polymer composites at synthesis, functionalization, and innovative structural design are discussed in detail. The main challenges and future development of boron nitride-polymer composites in thermal management are also proposed, which will provide meaningful guidance for the design and practical applications of thermal management materials.

The porous composites are positive for noise and electromagnetic wave shielding. Favorable microstructure is the key for realization of noise and electromagnetic co-shielding. Thus, the new method for CNT modification by the carboxylation and silver plating were developed in this study, and the modified CNT and polyimide (PI) were successfully fabricated into conductive aerogels. The modified CNT can effectively regulate the pore structure and conductive network through the interfacial reaction between carboxylation in CNT and polyamide acid. Attributed to a suitable pore structure and three-dimensional conductive network, the PI/CNT composite aerogel simultaneously achieved a sound absorption coefficient of 0.9 in 6000 Hz and an electromagnetic shielding effect of 28 dB in the X band through the absorbing mechanism. The satisfactory electromagnetic and sound shielding were integrated with the PI/CNT composite aerogel, representing a wider prospect of application in electronic and communicating equipment.

Thermal management material with excellent thermal conductivity is a key factor to the long-time operation of electronic elements. In this work, the polydopamine (PDA) modified boron nitride (BN-PDA) platelets were combined with polydimethylsiloxane (PDMS) to fabricate BN-PDA/PDMS composites to achieve enhanced mechanical properties and stable thermal conductivity performance under cyclic compression and thermo-oxidative testing conditions. The PDA functionalization of hexagonal boron nitride (h-BN) improved the dispersion and interfacial compatibility between h-BN platelets and PDMS matrix, which could benefit for the generation of effective thermal conducting route. The thermal conductivity of BN-PDA/PDMS composite at 26.7 wt

Biodegradable polymer foams have attracted extensive attention due to their advantages, like non-polluting degradation products, green environmental protection, light weight and high toughness. However, the foaming behavior of biodegradable polymer foams is difficult to regulate because of restriction by the crystallinity and melt strength of biodegradable polymers, which in turn affects performance stability and constrains their practical application. Accordingly, this study focuses on the strategies of foaming method, compositing filler and blending polymer to improve the foaming behavior of biodegradable polymer foams. The corresponding improvement mechanism for each strategy is analyzed and summarized in detail. Besides, the functionality and application fields of biodegradable polymer foams are also summarized. Finally, the future research direction of biodegradable polymer foams is proposed. This review aims to provide guidance for the study of cell structure regulation and performance expansion of biodegradable polymer foams.

Due to the miniaturization, integration and multi-functional development of contemporary electronic devices, there is a growing need for efficient thermal conductive composite materials. This study focuses on enhancing the dispersion of modified boron nitride (mBN) within a linear low-density polyethylene (LLDPE) phase by incorporating LLDPE-graft-Aminomethylpyridine (LLDPE-g-Py) to non-covalently modify BN. Additionally, polymethyl methacrylate (PMMA) and LLDPE polymers were introduced to create modified BN/LLDPE/PMMA (mBN/LLDPE/PMMA) composites with a double percolation structure. The co-continuous structure of the polymer composites was observed by using scanning electron microscopy (SEM). By selectively locating the BN modified by LLDPE-g-Py within the LLDPE phase, the co-continuous structure of the LLDPE/PMMA blend was upgraded to a double percolation structure. This double percolation structure establishes a dense and optimal heat transfer network within the polymer matrix. The thermal conductivity of the mBN/LLDPE/PMMA composite with BN loading of 40 wt% was significantly increased to 1.12 Wm-1 K-1, which was 350% higher than that of pure LLDPE, 38% higher than that of the BN/LLDPE composite, and 17% higher than that of the BN/LLDPE/PMMA composite. This study offers valuable insights into non-covalent modification techniques for BN and the design of double percolation structures in thermal conductive polymer composites.HighlightsThe double percolation structure was successfully constructed by simple melt blending method with LLDPE and PMMA as matrix and BN as thermal conductive filler. The double percolation structure can significantly promote the efficiency of heat transfer inside the thermal conductive composites.A novel non-covalent modifier LLDPE-g-Py was prepared to modify the surface of BN, and the selective localization of modified BN (mBN) in the LLDPE phase was realized. A novel non-covalent modifier LLDPE-g-Py was prepared to modify the surface of BN, and the selective localization of modified BN (mBN) in the LLDPE phase was realized, leading to an obvious enhancement of thermal conductivity of LLDPE/PMMA.image

Various acoustic materials are developed to resolve noise pollution problem in many industries. Especially, materials with porous structure are broadly used to absorb sound energy in civil construction and transportation area. Polyurethane (PU) porous materials possess excellent damping properties, good toughness, and well-developed pore structures, which have a broad application prospect in sound absorption field. This work aims to summarize the recent progress of fabrication and structure for PU porous materials in sound absorption application. The sound absorption mechanisms of porous materials are introduced. Different kinds of structure for typical PU porous materials in sound absorption application are covered and highlighted, which include PU foam, modified PU porous materials, aerogel, templated PU, and special PU porous materials. Finally, the development direction and existing problems of PU material in sound absorption application are briefly prospected. It can be expected that porous PU with high sound absorption coefficient can be obtained by using some facile methods. The design and accurate regulation of porous structures or construction of multilayer sound absorption structure is favorably recommended to fulfill the high demand of industrial and commercial applications in the future work.

Nickel iron (hydroxyl) hydroxide with unique layered structure and controllable composition is widely regarded as typical oxygen evolution reaction (OER) catalysts. Recently, developing top -down approaches to realize the facile preparation of transition metal hydroxide catalyst has received wide attention. Based on the natural microorganism corrosion behavior, this work demonstrates the external magnetic field -assisted microbial corrosion strategy to construct advanced transition metal hydroxide OER catalyst, and the prepared biofilm electrode presents superior OER performance in the existence of magnetic field, which needs an overpotential of 287 mV at 100 mA cm -2. Experimental and theoretical calculations show the applied magnetic field can accelerate sulfate reducing bacteria (SRB) corrosion and chemical corrosion. The additional magnetic field can promote SRB corrosion to produce FeS, which can facilitate the optimization of O intermediate desorption from the NiOOH catalyst during OER process, reducing the reaction energy barrier for O -> OOH. The synergistic effect between the nickel -iron oxyhydroxides originated from the accelerated chemical corrosion and FeS produced from the accelerated SRB corrosion interprets the improved OER activity. This work explores the influence of magnetic field on the construction of advanced OER materials, which can provide an effective magnetic fieldassisted corrosion engineering strategy, and promote the development of multidisciplinary fields of physics, biology, and emerging energy conversion technologies.

Polyurethane foam as an important sound absorption material is limited by the poor flame resistances in building field, but the modifications of flame resistances tend to have adverse effects on the sound absorption performance. Herein, dibutyltin dilaurate and triethylenediamine are used simultaneously as catalysts, and four new types of flame retardant polyether polyols (FPMPO) are synthesized and combined with modified expanded graphite (PEG) to prepare the flame resistance flexible polyurethane foam (FFPUF) by one-step method. The results show that the combination of the two catalysts can control the cell structure of FFPUF availably for sound absorption. The FPMPO have little negative influence on the cell morphology and the sound absorption performance of FFPUF, but the increase of flame resistances is finite due to the limited amount of FPMPO. In order to improve the flame retardant properties further, the FPMPO and the PEG are combined in the modification. Benefitting by the effective control structure and the modification with composite flame retardant, the FFPUF shows excellent sound absorption and flame retardant properties. The LOI value of FFPUF is 33.4 and the vertical burning level reaches V-0, and the average sound absorption coefficient maintains 0.68 in the 800-6300 Hz range.

The alleviation of the transmission for noise by using sound insulation materials has been regarded as an efficient route to control noise. In this work, the reinforcing effect on the sound insulating properties of polystyrene (PS) was successfully realized by using cetyltrimethylammonium bromide (CTAB) organically modified montmorillonite. The micrometer montmorillonite (MMT) was firstly organic modified by CTAB and then was melt blended with PS matrix to obtain high sound insulation polymer composites. X-ray diffraction results revealed that CTAB intercalation into MMT lamellar structure, leading to the increased lamellar space of the organically modified montmorillonite (OMMT). Moreover, the OMMT lamellar spacing was further enlarged by the intercalation of PS molecular chains. The sound insulation properties of all samples were tested by a four-microphone impedance tube. The average sound transmission loss (STL) of PS composites increased with the amount of OMMT. The average STL of PS/OMMT composite with the thickness of only 1.8 mm can reach to 35.46 dB when the weight fraction of OMMT was 30%, which is 36.0% higher than that of pure PS (26.08 dB). The sample thickness increased to 3.8 mm and the average STL up to 47.78 dB. Meanwhile, the storage modulus and thermal stability of PS were also enhanced by incorporating OMMT. This fabricating technique can provide a novel method to obtain low-cost and low-weight acoustic materials with high sound insulating properties.

Carboxymethyl cellulose (CMC) aerogel could be used in the manufacture of highly efficient sound-absorbing materials because of its low density and sustainability. However, owing to its low mechanical strength and brittleness, preparing porous sound absorption materials with excellent sound absorption performance has always been a challenging problem. Herein, carboxymethyl cellulose/organic exfoliation of montmorillonite/thermoplastic polyurethane (CMC/OMMT/TPU) composite aerogels were successfully obtained via a simple impregnation and freeze-drying process. The effect of TPU and OMMT on the sound absorption properties of cellulose aerogels was detailedly discussed. The results revealed that the CMC/OMMT/TPU composite aerogel had hierarchically porous structures, and the sound absorption performance was significantly improved. The average sound absorption coefficient of CMC/OMMT/TPU composite aerogel could reach as high as 0.807 (500-6500Hz). The main reason for this improvement is caused by the multiple scattering of sound waves on the arranged porous surface, as well as the viscous damping of the air inside the structure between the TPU, CMC and OMMT. Furthermore, the dimensional stability of the prepared aerogel is also greatly enhanced after using TPU. This work provides a new approach for the development of aerogel with stable morphology and sound absorption performance, which would be widely used in construction and military fields.

Given the abundant plastics produced globally, and the negative environmental impacts of disposable plastic products throughout their life cycle, there has been significant attention drawn by the general public and governments worldwide. Mono-material multilayer packaging is a potent strategy to address the challenge of carbon emissions as it offers specific functionalities (such as strength and barrier properties) through its layers and facilitates recycling. In this study, a five-layer co-extruded polyethylene composite film LLDPE/mPE/PVA/mPE/LLDPE was taken as a model to investigate its mechanical properties and barrier properties after four recycling cycles. The result revealed that the longitudinal tensile strength and transvers tensile were, respectively, dropped from 29.66 MPa and 24.9 MPa to 21.972 MPa and 19.222 MPa after the recycling; it is shown that the film still has good mechanical properties after the recycling cycle. However, a noticeable decline in the barrier properties was observed after the second recycling. In contrast to traditional plastics, a mono-material film with a 10 wt.% circulating mass could reduce CO2 emissions by 3692.25 kg for every 1.0 ton of plastic products after four recycling cycles.