SENSORS AND ACTUATORS A-PHYSICAL
·
2022
·
IF 4.291
Minghui Xie,Shuangxin Li,Xiaoming Qi,Zhangyi Chi,Luting Shen,Zahidul Islam,Yubing Dong
Wearable electronic gadgets have always been in great demand for multifunctional flexible strain sensors. However, developing a flexible strain sensor with excellent characteristics such as high sensitivity, wide sensing range, and excellent durability continues to be a significant challenge. On the one hand, the two-performance metrics of high sensitivity and wide sensing range are mutually exclusive, because the former requires significant structural changes under small strains, whereas the latter necessitates the preservation of morphological integrity under large deformations . On the other hand, the usage of flexible strain sensors is invariably accompanied by the destruction of the conductive network, rendering the device unusable for an extended period of time. Here, based on the unique strain related microcrack structure of the Ti 3 C 2 T x (MXene)/carbon nanotubes (CNTs) synergistic interaction and the shape memory property of ethylene vinyl acetate polymer (EVA), a MXene/CNTs/EVA fiber strain sensor was innovatively designed and prepared by swelling ultrasonic method. The results showed that the sensor combines a large strain sensing range (190%), high sensitivity (82.5), ultra-fast response speed (178.9 ms), and excellent durability and stability (> 10,000 cycles). What is even more exciting is that if the strain sensor is failure, it can be repaired by heating for 2 min or infrared irradiation for 5.4 s, and the mechanical and electrical properties of the repaired sensor can be restored to 92% and 94% of the original. In addition, this strain sensor can accurately monitor subtle and large movements of the human body (including elbow and finger bending, speaking, and mouth opening/closing), even if the damaged MXene/CNTs/EVA fiber strain sensor has been repaired. The self-repairing MXene/CNTs/EVA composites fiber-based shape memory matrix has excellent potential as a wearable strain sensor.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2023
·Vol. 301
·期 4
·293-302
·
IF 2.4
Duan Li,Guo Congshuai,Fan Jinlong,Duan Yufeng,Qiu Pengju,Huang Ping,Yan Junxia
Magnetically assisted separation method is a rapid and easy technique based on the separation and isolation of magnetic substance by the application of an external magnetic field. However, the service life of absorbents using polystyrene as skeleton is heavily shorted by the intrinsic brittleness of polystyrene. A novel method of preparing porous magnetic polystyrene particles modified with EVA targeting to eliminate the problems of homogeneous polystyrene is described. The optimum hydrophile-lipophilic-balance (HLB) value, phase inversion temperature, and cloud point of the combined emulsifier selected in this work are analyzed and the optimized preparation conditions are determined accordingly. TEM and SEM show that the particles have a morphology structure that most of Fe 3 O 4 particles are embedded in the interior. The dimension distribution of the pores in porous PS/EVA/Fe 3 O 4 particles mainly belongs to mesopore. XRD indicates that the Fe 3 O 4 particles keep their intrinsic crystal structure in the prepared porous magnetic particles.
研究领域:
材料科学
·
化学工程
·
纳米技术
·
高分子科学
·
分析化学
✓ 已验证
DOI
高影响因子
Materials Horizons
·
2025
·
IF 10.7
Hongfei Liang,Lu Chen,Yang Wu,Youwen Xue,Yuxuan Wang,Wenjie Ji,Huanqi Cao,Qian Zhao,Jian Song,Guoran Li
Luminescence down-shifting technology is increasingly recognized as a crucial option for enhancing the efficiency of silicon solar cells. However, high-quality down-shifting materials, such as perovskite quantum dots, face challenges related to poor thermal stability. These materials tend to agglomerate into larger sizes, leading to the deterioration of the luminescence films at high temperature. Unlike introducing a protecting layer on perovskite quantum dots, we applied 3-aminopropyltriethoxysilane (APTES) as a direct capping agent for perovskite quantum dots in this work to achieve both efficient and stable composite down-shifting films. The interaction between APTES and CsPbBr3 quantum dots is thoroughly analyzed using both experimental measurements and theoretical calculations. Due to the strong interaction between APTES and CsPbBr3, an optimal amount of APTES effectively stabilizes the quantum dots. When mixed with ethylene-vinyl acetate (EVA) copolymer, the strong interaction between APTES and polymer chains could suppress the aggregation of CsPbBr3 quantum dots and inhibit degradation of the composite film under heating. Upon coating on commercial crystalline silicon solar cells, the optimal CsPbBr3 quantum dot/EVA composite film achieves an absolute efficiency by 1.00%, maintaining a 0.81% efficiency improvement even after annealing at 90 °C for 3 hours. In contrast, while the film without APTES shows an efficiency improvement of 0.63% at room temperature but experiences a decrease of 0.23% under the same heating conditions. This work provides a feasible strategy to enhance the thermal stability of CsPbBr3 quantum dot/EVA composite films under high-temperature conditions, offering a promising path toward the commercial application of perovskite-based luminescence down-shifting films in silicon solar cells.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2025
·
IF 4.5
Zhipeng Liu,Zhe Liu,Pinzhe Luo,Wei Cui,Shicheng Zhao
During prolonged operation of photovoltaic modules, the Ethylene-Vinyl Acetate Copolymer (EVA) encapsulant film is prone to aging and degradation, which significantly reduces the service life of the modules. In this study, reactive hindered amine light stabilizers (rHALS) were chemically grafted onto EVA backbone to prepare hindered amine-grafted EVA (EVA-g-HALS) and the influence of EVA-g-HALS on the photoaging behavior of EVA photovoltaic encapsulant films was systematically investigated. Firstly, the strategy of directly forming EVA-g-HALS during the crosslinking process of EVA photovoltaic encapsulant film was investigated. Fourier-transform infrared spectrum (FTIR) results revealed that rHALS underwent self-polymerization before crosslinking, making it impossible to form EVA-g-HALS during the crosslinking process. Subsequently, reactive extrusion was employed to prepare EVA-g-HALS and X-ray photoelectron spectroscopy results confirmed the successful synthesis of EVA-g-HALS. Then the effect of EVA-g-HALS on the photoaging behavior of EVA photovoltaic encapsulant films was investigated. The FTIR results indicated that after 800 h of photoaging, the addition of EVA-g-HALS reduced the growth amplitude of degradation-induced carbonyl absorption peak intensity by 70 %, whereas direct addition of rHALS only achieved a 23 % reduction. Rheological and crystallization behavior studies revealed that EVA-g-HALS effectively prevented the degradation of the crosslinked network in EVA photovoltaic encapsulant films, as evidenced by nearly unchanged storage modulus and crystallization temperature. These findings confirm the superior anti-aging performance of EVA-g-HALS compared to several commercial HALS. Finally, mechanism of superior anti-photoaging performance of EVA-g-HALS was revealed by combination of experiment and molecular simulation method. The EVA-g-HALS possesses enhanced migration resistance and outstanding compatibility with the EVA matrix, thereby exhibiting superior anti-photoaging performance. This research could provide a new strategy and inspiration for developing high efficiency anti-aging additives for EVA photovoltaic encapsulant films.
研究领域:
高分子科学
·
材料科学
·
光伏技术
·
聚合物降解与稳定性
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2023
·
IF 4.4
Guanyu Wang,Dan Xu,Jiaqi Tang,Bingzhi Liu,Zhandong Wang,Qiang Xu,Yanjun Hu,Jinsong Zhou,Shurong Wang
As an important component of organic solid wastes, disposal of plastic wastes (PWs) has always been a thorny issue. Thermochemical conversion is an efficient method. In-depth research on the influence of structural differences on their pyrolysis behavior is beneficial to promote the development of thermal treatment and conversion technology of PWs. The differences in the chemical structure of different polyolefin plastics at the molecule level are mainly reflected in their side chains. Herein, a series of typical polyolefin plastics with similar backbone structure and different side chain structures, including high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyvinyl alcohol (PVA) and ethylene-vinyl acetate copolymer (EVA), were selected for comprehensive pyrolysis characterization in this work. Advanced experimental analysis methods such as in-situ DRIFT and 2D-PCIS were adopted to investigate the evolution of two weak oxygen-containing side chains during pyrolysis of PVA and EVA, respectively. Besides, typical product distribution of six samples were systematically studied by combining SVUV-PIMS and GC/MS. Spectral analysis showed that OH side chain in macromolecular structure of PVA had the weakest thermal stability, and its oxidation reaction occurred earlier than dissociation and dehydration, while the acetoxy side chain in EVA polymers could not only be directly dissociated via deacetoxylation, but also be transformed into OH side chain via deacetylation that occurred simultaneously with deacetoxylation. Further combined with SVUV-PIMS and GC/MS, the distribution characteristics of pyrolysis products of polyolefin plastics and the rules of generation and release of typical products with temperature were obtained in detail. It was found that the release of typical oxygen-containing products was earlier or slightly earlier than the release of hydrocarbons in pyrolysis of PVA or EVA. However, the release of all hydrocarbons was almost simultaneous during the respective pyrolysis process of HDPE, PP and PS, suggesting that the evolution of oxygen-containing side chains with weak thermal stability occurred earlier under the drive of temperature. Based on the characterization results, the main evolution pathways of different side chains were proposed to explain the influence mechanism of different side chain structures on the pyrolysis behavior of polyolefin plastics. The cleavage of C C bonds mainly occurred in HDPE, PP and PS, while the evolution of side chains occurred first in PVC, PVA and EVA, and exerted different influence on the degradation of carbon skeleton.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2021
·
IF 7.267
Sheng Pang,Yang Yan,Zhi Wang,Dong Wang,Shijian Li,Wenhui Ma,Kuixian Wei
With the rapid increase of photovoltaic (PV) system production and installation, the recycling of end-of-life PV modules has become a grave issue. In this paper, a new method of microwave-enhanced EVA film swelling and separation for PV panels recycling was innovatively proposed. The results showed that the separation speed of different layers in microwave can be significantly accelerated. Different swelling agents were compared and trichloroethylene was proved to be the most effective. The analysis of dielectric loss and thermal expansion coefficient (TEC) of different layers indicated that the good absorbing property of antireflection layer and the difference of TEC accelerate the swelling separation. Different conditions such as temperature and liquid-solid ratio were also carried out to optimized separation. The mechanism of microwave enhanced EVA swelling has been analyzed by thermogravimetry and infrared analysis. This study has a good guiding significance for the green and efficient recycling of PV panels.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 26
·16615-16623
·
IF 4.036
Gaobo Lou,Qing Li,Qian Jin,Qingqing Rao,Shenyuan Fu,Jinfeng Dai
Solid epoxy resin is highly desired in adhesives, electronic materials and coatings due to the attractive characteristics of solvent-free, highly efficient utilization and convenient storage and transportation. However, the challenges remain in fabricating high-toughness solid epoxy resin through a facile and efficient way. Here, a high-performance environment-friendly solid epoxy resin was fabricated by employing maleic anhydride grafted ethylene-vinyl acetate copolymer (EVA-g-MAH) as the flexibilizer via one-step banburying method. The results showed that the modified epoxy resin maintained a high glass transition temperature (Tg) and thermal stability, while its impact strength, tensile toughness and flexural toughness were significantly increased compared with the neat epoxy resin. The impact strength, tensile toughness and flexural toughness of R-EM10 are improved 138%, 195% and 149%, respectively. The EVA-g-MAH was introduced in the epoxy matrix as a separate phase to increase toughness via transfer stress and dissipated energy. The attractive properties of this facile fabrication process and the high-toughness, as well as the environment-friendly performance make this solid epoxy highly promising for large-scale industrial application.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Ruilong Xu,Wei Liu,Yiting Jiang,Shuai Zhao,Lin Li
The latent heat of phase change in iPCMs reaches up to 110.14 J/g. • iPCMs are flexible materials with a maximum elongation at break of up to 527.25%. • iPCMs exhibit excellent dimensional stability and recyclability. • The transverse thermal shrinkage rate of FEVA-iPCMs decreased by 56.05%. • The longitudinal thermal shrinkage rate of FEVA-iPCMs has been reduced by 57.66%. Developing organic phase change materials that simultaneously exhibit high latent heat, shape stability, and recyclability remains a significant challenge, particularly in achieving an effective balance between suppressing phase change component leakage and maintaining high latent heat. In this study, we constructed a crosslinked framework via esterification between polyethylene glycol (PEG) and pyromellitic dianhydride (PMDA) and introduced zinc acetate to form a dynamic ionic crosslinking network; meanwhile, ethylene-vinyl acetate (EVA) provided flexibility and encapsulation support, enabling the successful fabrication of a recyclable, high-latent-heat, flexible solid-solid phase change material (iPCMs). We systematically investigated the effects of the equivalent ratio of PEG to PMDA on the structural characteristics, thermal behavior, rheological properties, mechanical performance, and recyclability of the iPCMs. The results demonstrate that the as-prepared iPCMs achieve a phase change latent heat of up to 110.14 J/g and a maximum elongation at break of 527.25%, while exhibiting excellent recyclability, stable shape retention, and well-preserved performance after 100 thermal cycles. Furthermore, we incorporated the iPCMs into an EVA foaming system, where the iPCMs not only restricted EVA molecular chain mobility through the ionic crosslinking network but also slowed gas diffusion within the cells and thermal relaxation of the EVA matrix via a phase change-induced temperature-regulating effect, thereby significantly improving the dimensional stability of EVA foams at 70 °C. Specifically, the transverse and longitudinal shrinkage rates of FEVA-iPCMs-4.5 are 1.89% and 1.77%, respectively, representing reductions of 56.05% and 57.66% compared with those of FEVA. This study provides a viable new pathway for developing high-performance, recyclable composite phase change materials and for realizing their functional applications in polymer foaming systems.
✓ 已验证
DOI
高影响因子
SOLAR ENERGY
·
2025
·
IF 6.6
Chenyang Li,Liqian Zhao,Feihong Guo,Xiaoxiang Jiang,Yuxiu Duan,Wensheng Xu
Solar energy, with its advantages of safety, reliability, cleanliness, and wide distribution, has seen a significant increase in photovoltaic (PV) installations. However, this growth has led to a large number of end of life PV modules. The adhesive effect of EVA (ethylene–vinyl acetate) makes it difficult to effectively separate and recycle the various layers of these modules. Therefore, the key to recycling silicon PV modules lies in removing or weakening the adhesive properties of EVA while protecting core components such as silicon from damage, thereby achieving efficient separation and recycling of the layers. This paper proposes a novel green treatment method using N-methylpyrrolidone (NMP) as a solvent for recycling discarded PV modules. Through experimental studies, we investigated the effects of different NMP treatment conditions-including temperature, time, sheet size, and rotor speed-on the reaction rate of EVA. The optimal processing condition was found to be heating at 150 °C for 45 min. Kinetic fittings were performed under various conditions, and parameters were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and contact angle measurements. The mechanism of the reaction between NMP and EVA was analyzed. Finally, experiments were conducted on Commercial PV modules to develop a fundamentally harmless recycling process. A life cycle assessment of this recycling process was also carried out, providing theoretical guidance for future applications of NMP in the treatment of waste silicon PV modules.
研究领域:
材料科学
·
环境科学
·
能源技术
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2018
·
IF 4.514
Wenbing Li,Yanju Liu,Jinsong Leng
In the current study, a novel polymer composite with excellent light-actuated two-way shape memory effect (2W-SME) was fabricated using poly (ethylene-co-vinyl acetate) (EVA) as matrix and p -aminodiphenylimide ( p -AP) as both light-absorber and heat source (EVA/ p -AP). Unlike traditional thermally-driven two-way reversible shape memory polymers, in our concept, the EVA/ p -AP featured remotely controlled and light-manipulatable reversible two-way shape memory behaviors. Utilizing the distinct light-responsive behavior of p -AP in the irradiation of 365 nm ultraviolet (UV) light, the EVA/ p -AP composite exhibited excellent light-actuated reversible 2W-SME by a light-manipulated procedure. The results from this study indicated that the composite material could have greatly potential applications in soft reversible drivers.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Yiming Zhang,BingBing Li,Dongxian Zhuo,Youliang Lu,Hezhi He,Zhiwen Zhu
An ethylene-vinyl acetate copolymer (EVA) has been widely applied in various fields due to its excellent foaming properties and modification compatibility. To address the potential health risks posed by chemical foaming agents, supercritical fluid foaming has been applied through autoclave batch processes. However, due to the required vulcanization process, applying supercritical injection foaming to EVA remains challenging. Considering the advantages of a shorter process and high automation of injection molding, we successfully prepared high-performance EVA composite foams using a newly developed supercritical in-mold vulcanization injection molding (SIVIM) process in this work. The evolution during the in-mold vulcanization process was first analyzed, and the optimal vulcanization temperature and time were found to be 180 °C and 300 s, respectively. Subsequently, the effects of gas concentration and gas counterpressure on product performance were investigated. The results showed that the gas concentration is the key factor influencing foam density. When the gas concentration reached 1.8 wt %, the initial product density decreased to 0.195 g/cm3. Additionally, an increase in gas counterpressure improved nucleation efficiency, resulting in a foam structure with a higher cell density and smaller cell size. Compared to the batch foaming process, the SIVIM process reduces the molding cycle time by over 90%, while producing foams with comparable density and superior overall mechanical properties. This work provides an innovative approach, enabling the production of EVA composite foams through supercritical injection molding, which will significantly promote the sustainable development and modernization of the EVA products.
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Materials and Technologies
·
2025
·
IF 9.2
Ziwei Qin,Yaozong Li,Hanyi Huang,Yushu Wang,Zelin Wang,Fangwei Tian,Junjie Jiang,Wentao Zhai
Cross-linked ethylene-vinyl acetate copolymer (EVA) possesses excellent mechanical properties that are widely used in sports and the photovoltaic industry, but it cannot be recycled through melt reprocessing. The emergence of dynamic chemistry provides a viable approach to achieve both high mechanical performance and recyclability in cross-linked EVA. Herein, this study fabricated a dual cross-linked EVA containing covalently cross-linked sites and dynamically cross-linked sites, which improved the mechanical properties and endowed it with reprocessability. The optimal cross-linking network structure was determined, and the bond exchange was clarified through chemical, rheological, and mechanical analysis. The dual cross-linked EVA could be well foamed through supercritical fluid and the foaming temperature was broadened to 180 °C. Low-density and uniform cell structure was obtained for the dual cross-linked EVA foam that exhibited excellent cushioning performance, the peak impact force was reduced from 8081 N to 1281 N, and achieved a superior energy absorption efficiency of 84.1 %. Meanwhile, the dual cross-linked EVA foam could be recycled through a re-foaming strategy. This study demonstrates that incorporating dynamic bonds into the covalent network is beneficial for balancing mechanical properties and recyclability, which provides a valuable insight for designing recyclable and cushioning EVA foam.
研究领域:
材料科学
·
高分子化学
·
机械工程
·
回收技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）