CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ke Wang,Wei Gao
Efficient thermal insulation and flame-retardant materials are crucial in reducing energy consumption and minimizing fire hazards. This work presents a novel method for preparing a composite aerogel: a silane coupling agent was used as a chemical bridge to synthesize a new flame retardant AKH (modified APP with HNTs). AKH was incorporated into the silica sol to fabricate the SA-AKH composite aerogel. SA-AKH features a dense three-dimensional network skeletal structure, excellent thermal stability, and a high specific surface area. When integrated into organosilicon resin, SA-AKH significantly enhances the flame resistance of composite materials. During cone calorimetry testing (CCT), SSAKH4 exhibited a peak heat release rate (PHRR) of 281.88 kW/m 2 and total smoke production (TSP) of 5.52 m 2 , representing a decrease of 30.8 % and 4.5 %, respectively, compared to SSA4. The composite material, derived from the unique mesoporous structure of aerogel combined with the flame retardant and hollow characterization of AKH, demonstrates exceptional flame retardancy and smoke suppression. SA-AKH is expected to make novel advancements in the field of high-efficiency insulation and flame-resistant composites.
研究领域:
材料科学
·
能源工程
·
防火材料
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Yang Yang,Yuxin Chen,Yiqin Li,Chenrui Hao,Zhaoping Song,Peng Lu,Zhiwei Wang
Nanocellulose has attracted extensive attention in the preparation of thermal insulation materials because of its high Young's modulus, high strength and low thermal expansion coefficient. In this study, nanocellulose microgels prepared by self-assembly of 2,2,6,6-Tetramethylpiperidoxyl oxidized nanocellulose (TOCNC) and Nisin were used as particle stabilizers, and acrylated epoxidized soybean oil (AESO) was used as oil phase to prepare Pickering emulsion, which was cured by heating to obtain biomass-based Pickering thermal insulation foam. Pickering foams prepared based on microgels with different Nisin contents have significant differences in thermal insulation performance. The results show that the addition of microgel particles can improve the thermal stability, increase the roughness of pore wall and reduce the thermal conductivity of AESO polymer foam. Among them, the Pickering foam prepared by microgel containing 0.06 wt% Nisin has the best thermal insulation performance and rougher pore wall surface, and its thermal conductivity is 0.040 W/(m·K), which is obviously lower than that of the foam prepared by TOCNC (0.083 W/(m·K)). Based on the structural design of nanocellulose microgel particles, this work innovatively realized the assembly of microgels at the oil-water interface and the regulation of thermal insulation performance through Pickering technology, and developed a biomass-based foam with improved thermal insulation effect, which provides a new idea for expanding the advanced application of nanocellulose in the field of thermal insulation materials.
研究领域:
材料科学
·
生物材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Youxian Yan,Fang Ge,Yu Qin,Mengya Ruan,Zeyong Guo,Chuanxin He,Zhongkai Wang
The development of lightweight, strong and high-performance thermal insulators from renewable biomass are highly desired for sustainable development. Here, ultralight aerogels based on renewable nanochitin with outstanding mechanical properties, excellent water-resistant, and promising thermal insulation properties are fabricated. The pristine nanochitin aerogels (PNCAs) assembled from mechanically strong carboxylated chitin nanorods are firstly prepared through acid-induced gelation and supercritical drying. The resultant PNCAs present tunable density (10−50 mg/cm 3 ) and strong mechanical stiffness (the specific compression modulus of 30.2 MPa cm 3 /g) combining with low thermal conductivity (27.2 mW/m K). After a facile silylation modification, the silylated nanochitin aerogels (SNCAs) exhibit hydrophobic behavior (contact angle >130°), improved compression performance (the specific compression modulus of 65 MPa cm 3 /g), and promising thermal insulation property (30.5–35.8 mW/m K). Moreover, the silylated aerogel shows a negligible loss of mechanical performance when exposed to water for 12 h at 35 °C.
研究领域:
材料科学
·
生物质工程
·
可持续发展
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HIGH PRESSURE RESEARCH
·
2018
·
IF 1.925
Akun Liang,Yinjuan Liu,Hao Liang,Fangming Liu,Cong Fan,Jiawei Zhang,Jinjun Wu,Ji Chen,Duanwei He
The thermal insulation performance of cubic ZrO2–CaO solid solution (CSZ) (16 mol % CaO) and monoclinic ZrO2 (MZ) was investigated in a two-stage multi-anvil press under a pressure of 10 GPa and temperatures up to 1800°C through in situ temperature measurements with the same cell assembly. The results show that the cell temperatures with CSZ as the thermal insulator were always higher than that when thermal insulator was MZ at the same heating power, and the maximum deviation value was 600°C (50% higher) within the measurable range. These two materials were analyzed using X-ray diffraction (XRD), thermal conductivity measurement and scanning electron microscopy. It revealed that the point defects existed in CSZ dominated the thermal insulation performance at high pressure, the same as what at normal pressure. It was also found that the heating process was more controllable when using CSZ as thermal insulator under high pressure.
研究领域:
材料科学
·
热物理
✓ 已验证
产品关联
DOI
高影响因子
PHYSICA SCRIPTA
·
2025
·Vol. 100
·期 3
·035966
·
IF 2.6
Chunxin Wang,Jun Xie,Qi Liu,Yaxuan Liu,Qing Xie
According to the problems of poor insulation and local temperature rise of polypropylene film, a new nano-filler was studied, and the mechanism of improving insulation and thermal conductivity was analyzed. TiO2 with high dielectric constant is combined with Al2O3 with excellent thermal conductivity in the form of a core–shell structure. TiO2 increases the dielectric constant of polypropylene films, and shell Al2O3 introduces high thermal conductivity and assumes the role of dielectric buffer layer. Compared with pure PP, the breakdown voltage of PP/TiO2 is increased by 6.05%, the thermal diffusivty coefficient is increased by 110.67%, the breakdown voltage of PP/TiO2@Al2O3 is increased by 37.05%, and the thermal diffusivity coefficient is increased by 266.85%. Experimental and simulation results show that TiO2 introduces low-density traps, TiO2@Al2O3 introduces high-density deep traps, and Al2O3 modifies the surface defects of high-dielectric nanoparticles and increases the equivalent interface region. Based on the analysis of the experimental results with different mass fractions, this paper proposes the optimal filling ratio of the new core–shell, which provides a new method for the composite dielectric to improve the insulation and thermal conductivity at the same time.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Ze Zong,Penggang Ren,Zhengzheng Guo,Jin Wang,Zhengyan Chen,Yanling Jin,Fang Ren
The development of electromagnetic interference (EMI) shielding materials with excellent absorption coefficient (A) is vital to completely eliminate the pollution of the ever-increasing electromagnetic waves (EMWs). In this regard, a TiC/carbon hybrid aerogel , derived from MXene/cellulose aerogel, was successfully fabricated via freeze-drying and subsequent pyrolysis process . Profiting from the open, loose three-dimensional (3D) macro pores with sheet-like morphology and high porosity, as well as the rich heterogeneous interfaces between TiC and cellulose-derived carbon, the as-prepared hybrid carbon aerogel achieves ultra-efficient EMI shielding effectiveness of 72.9 dB in conjunction with a superior A value of 0.76 and low thermal conductivity . These properties endow the as-prepared aerogel with strong absorption-dominant ultra-efficient EMI shielding and thermal insulation performance to meet the complex practical requirements. This work provides a promising strategy for achieving ultra-efficient multifunctional EMI shielding performance and superior A simultaneously.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yu He,Qili Zhou,Wen Wang,Zitan Yang,Zhi Liang,Zhangcheng Li,Honghao Cao,Chong Hou
Polyimide (PI) foams possess excellent mechanical properties and high-temperature resistance, which present significant utility in the aerospace, transportation, and microelectronics industries. The microstructure of PI foam, specifically the pore size and porosity, significantly influences its physical and mechanical properties. However, achieving both high porosity and small pore size simultaneously is greatly challenging for PI foams, especially via the foaming method. Here, we report PI foams with mean pore size of 98.1 μm and porosity of 92 % using a one-step scrape foaming method. The scraping thickness is found to be key to adjusting the pore size of the foam due to the interface effect in the initial stage, and maintaining optimal air pressure and low temperature allows slow bubble growth without bursting or merging, resulting in PI foams with high porosity and small pore size. The PI foam we fabricated exhibits excellent thermal insulating performance, with a low thermal conductivity of 20 mW/m∙K. The scrape foaming method provides an efficient and low-cost strategy for the preparation of PI foams with a tunable porous structure and is expected to find a variety of applications in thermal insulation and environmental protection.
研究领域:
材料科学
·
热能工程
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lin Wang,Liguang Yang,Dehua Ma,Chonghe Xu,Xiaojing Liu,Xinzhu Gan,Pinghui Ge,Luyi Zhu,Gaocheng Zhang
In this study, grooved TiO 2 /ZrO 2 ceramic fibers were prepared via coaxial electrospinning, which exhibit enhanced thermal insulation and superior mechanical properties. The fibers were architected with a distinctive core-shell structure, comprising a TiO 2 shell that serves as an effective radiation shield and a ZrO 2 core that maintains mechanical robustness. The interdiffusion of Zr and Ti atoms at the interface facilitated a seamless transition between TiO 2 and ZrO 2 , effectively inhibiting TiO 2 grain coarsening and substantially enhancing the tensile strength of the fibers, exemplified by the 1.47 ± 0.08 MPa achieved in the TZ-5 sample. Through control of the injection rate during electrospinning, we optimized the fibrous morphology to attain a synergistic balance of strength, flexibility and thermal insulation. The fibers showcased exceptional thermal insulation properties with thermal conductivity values ranging from 0.0294 to 0.0278 W m −1 K −1 and an average infrared reflectance exceeding 87 %. Practical thermal insulation tests confirmed the superior insulation performance of the TiO 2 /ZrO 2 fibrous membranes.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Wei Kong,Linlin Jiang,Guodong Jiang,Jun Zhang,Xiaodong Shen
In order to overcome the brittleness of traditional aerogels , we report the copolymer of polysiloxane as a precursor for the fabrication of high-performance aerogels . The copolymer of poly (methyl methacrylate-co-vinylmethyldimethoxysilane) was synthesized by radical copolymerization , using methyl methacrylate (MMA) and vinylmethyldimethoxysilane (VMDMS), and multifunctional silane compounds including the VMDMS, vinyltrimethoxysilane (VTMS) and tetraethyl orthosilicate (TEOS) were used to promote the formation of the cross-linked network. Our reported aerogels have excellent mechanical properties and stability. Moreover, the recovery of these aerogels can be improved by more than 14% after heat treatment, which can recover over 80% of the original height. The morphologies and microstructures of these co-polymer aerogels were characterized by field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) and pore size distribution . The structural and chemical compositions were analyzed by 1 H NMR spectra and Fourier transform infrared spectra (FTIR). The thermal analysis was evaluated by differential scanning calorimetric (DSC) and thermogravimetric analysis (TG), and the thermal insulation properties and the mechanical properties were determined by a thermal conductivity analyzer and uniaxial compression testing, respectively. The specific compressive strength of our reported aerogels is in the range of 6.99–27.70 MPa, the multi-point specific surface area is in the range of 752–1271 m 2 g -1 , and thermal insulation performance is 0.030–0.061 W m −1 K −1 . Finally, we suggest that radical copolymerization can also be employed for other co-polymer aerogels, including the monomers of C C double bonds.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 13
·8751-8769
·
IF 5.044
Liu Jinru,Yu Zhicai,He Hualing,Wang Yushu,Zhao Yuhang
Abstract Design and development of fire-resistant composite materials with improved flame retardancy are critically needed for firefighters in fire protection fields. Herein, a novel fire-resistant composite hydrogel (FRCH) was fabricated based on calcium alginate (CA), poly (vinyl alcohol) (PVA) and expandable graphite (EG). The obtained FRCH material displayed prominent flame retardancy due to a large amount of heat was removed as contained water evaporation. Meanwhile, the EG in hydrogel occurred expansion to prevent heat transfer when exposed to fire. Results indicated that peak heat release rate and total release rate of FRCH decreased from 264.9 to 67.2 W/g and 15.4 to 12.1 KJ/g, respectively. The thermal kinetic behavior of FRCH was investigated by using Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) models. TPP test further confirmed that introduction of EG in hydrogel prolonged the second-degree skin burn time for 2.73 s compared to without EG component. Besides, benefiting from the expansion behavior of EG when being burned, EG formed a conductive pathway and resulting in LED light up. This work provided an effective way to prepare flame retardant composite material with an early fire warning detection function, which may meet the requirements in firefighting fields. Graphic abstract
研究领域:
材料科学
·
燃烧学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yongshuai Xie,Lin Wang,Ying Peng,Dehua Ma,Luyi Zhu,Guanghui Zhang,Xinqiang Wang
At high temperatures, lightweight ceramic and aerogel materials have serious problems such as volume shrinkage, increased density, loss of flexibility, and decreased thermal insulation performances. The research on high-performance, lightweight, and flexible materials, which can meet the requirements of high-temperature applications, is a challenging topic in the industry. In this work, we developed a defective fluorite phase Y 2 Zr 2 O 7 flexible fibrous membrane (YZFM) material which has excellent thermal stability, no phase change until 1200 °C, and excellent flexibility until 1200 °C. The dense single fiber structure results in the tensile strength of the YZFM as high as 8.27 MPa. The low density (44 mg/cm 3 ), high porosity (99.2%), and excellent heat radiation reflectivity (750–2500 nm: Avg. 96.34%) endow the YZFM with outstanding thermal insulation performance (the thermal conductivity: 38 mW m −1 K −1 ). The 30 mm thick YZFM can reduce the high temperature of 1260 °C to 185 °C. The anisotropic layered structure makes YZFM have better acoustic absorption performance than commercial materials. These robust performances make our YZFM suitable for fields with strict requirements on material usage conditions, such as aerospace and cutting-edge industries.
研究领域:
材料科学
·
工程热物理
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 55
·34828-34835
·
IF 3.361
Yueyan Sun,Weiwang Chen,Xiaomeng Zhou
Kevlar aerogel fibers which inherit the aerogel's brilliant properties of low density, high porosity and large surface area are promising candidates for thermal insulation applications in textiles. To enhance the mechanical strength of Kevlar aerogel fibers, an extra Nomex shell was introduced by a simple coaxial-wet-spinning approach. The resultant coaxial fibers were observed to have a Kevlar aerogel core and a porous Nomex shell. Besides, there also formed an air gap between the core and the shell. This multi-layered coaxial structure with numerous pores inside contributes to the excellent thermal insulation performance of the fibers and their fabrics. The temperature differences between the hot plate and the outer surface of the fabrics were measured to be as high as 80 °C when exposed to a temperature of 300 °C. In addition, these fibers also performed well in thermal stability, and almost did not decompose before 380 °C. Not only that, the breaking strength of the Nomex shell can be up to twice that of the Kevlar core, resulting in a significant improvement in the fiber's mechanical strength. It can be envisaged that the developed coaxial fibers with excellent thermal insulation and endurance properties as well as improved mechanical strength may have broad prospects for thermal insulation at high temperatures.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）