PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2019
·
IF 4.384
Xiaoyang Yu,Ning Jiang,Xuyang Miao,Fan Li,Jiyun Wang,Ruowen Zong,Shouxiang Lu
The application of fluorocarbon surfactants in fire-fighting foam has been restricted due to their serious environmental hazards. Thus, it is necessary to develop the fluorine-free foam for fire-fighting and understand their characteristics from different perspectives compared with the fluorinated foam. The present study investigated foam stability, oil-film interaction, and fire extinguishing performance for fluorine-free and fluorinated foams. The results show that the adverse effect of oil on the stability of fluorinated foams is much less than that of fluorine-free foams. Besides, the trends in foam stability are not predicted by the entering, spreading, and bridging coefficients based on the measurement of surface and interfacial tensions. The differences in stability of fluorine-free and fluorinated foams are found to be consistent with the observation of oil-film interaction. Oil droplets destabilize the fluorine-free film by spreading over the film, whereas they tend to be rapidly expelled out of the fluorinated film in the form of oil lenses slightly affecting the film stability. Since the film is unstable in contact with oil, the fluorine-free foam cannot suppress the pool fire effectively at the expansion ratio of 6.8–7.2. By adjusting the foam expansion ratio, the fire extinction performance of the fluorine-free foam can be comparable to that of the fluorinated foam, and the burnback performance is significantly enhanced.
研究领域:
消防工程
·
表面化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Thermal Science and Engineering Progress
·
2022
·
IF 4.56
Yunpeng Yang,Haolan Tan,Jiaqing Zhang,Fengju Shang,Fei Xiao,Kaiyuan Li
This work presented a systematic study on the surface activity and foam performance of Gemini short-chain fluorocarbon surfactant (Gemini) solutions mixed with anionic, zwitterion, and non-ionic hydrocarbon surfactants. The results show that Gemini exhibits good surface activity and foam properties. The compounding of Gemini and three ionic hydrocarbon surfactants presents a good synergy, and with the increase of Gemini concentration, the foam performance improved. Gemini improves the foam performance by enhancing the alignment of surface adsorbed molecules at the liquid–air interface. Among all mixed systems, the Gemini/SDS shows the strongest foam stability. Compared to single SDS aqueous solution, the foam filtration time of mixed solution increased by 182.17 % with the addition of Gemini. The average bubble area in 30 min decreases by 8.03 %-46.32 %. The addition of Gemini slightly inhibited the foam coarsening of SDS solution when the Gemini concentration was 0.01 wt%. The foam coarsening process was significantly inhibited when the Gemini concentration was 0.1 wt%. The results of the present study are meant to provide guidance for the practical application of foams generated by the mixtures of the Gemini and hydrocarbon surfactants.
研究领域:
化学
·
材料科学
·
胶体与表面化学
✓ 已验证
产品关联
DOI
高影响因子
Asia-Pacific Journal of Chemical Engineering
·
2024
·
IF 1.4
Yixiang Zhang,Shilong Feng,Yuhui Jing,Junhua Bai
High expansion (Hi-Ex) foam is recommended to suppress the leakage and diffusion of cryogenic liquid due to its light weight and large volume. However, the disadvantages of low stability and high break rate under environmental conditions are all limited the further application in vapor mitigation and fire extinguishing. So that, this paper focus on the effect and mechanism of nanoparticles in stabilizing Hi-Ex foam. Three kinds of nanoparticles with different concentration were selected to evaluate the effect of foam half-life and the mechanism of particles on improving the foam stability. The results indicated that different particle concentrations can improve the foam stability to a specific extent, and the maximum improving of half-life can increase by 95.4% in the presence of the hydrophilic SiO 2 at .5 wt%. Meanwhile, the hydrophilicity, size, and morphology of the particles have a specific impact on the foam stability. The foam expansion rate first increased and then decreased. From the microscopic point of view, the bubble size gradually increases with time by two processes of ripening and coalescence and satisfied in a logarithmic distribution. While, the liquid film thickness remarkably decreases due to foam drainage without particles and the adsorption and accumulation of nanoparticles on foam lamella can provide a spatial barrier for the film thinning and the inter bubble diffusion. Finally, the microscopic interaction mechanism on improving the foam stability has been further explored and revealed in these two aspects.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Andong Feng,Dmytro Dedovets,Yunjiao Gu,Shi Zhang,Jin Sha,Xia Han,Marc Pera-Titus
Hypothesis Can surface-active particles be designed à la carte just by incorporating functional groups mimicking the structure of the solvent and gas ? This is based on the idea that, to achieve good foamability, the particle wettability needs to be finely tuned to adjust the liquid-particle and gas-particle surface tensions. In practice, could particles containing phenyl rings and alkyl chains assemble at the air–liquid interface and stabilize foams based on aromatic solvents ? Experiments A library of organosilica particles was prepared by sol–gel synthesis using aromatic organosilane precursors. The particles were characterized by TGA , FTIR and 13 C/ 29 Si MAS NMR. The foaming properties were studied after hand shaking and high-speed homogenization . The influence of particle wettability and solvent properties on foam formation was systematically investigated. A comparison was carried out between biphenyl-bridged particles and various stabilizers on foamability in benzyl alcohol . Findings Biphenyl-bridged particles could stabilize foams in aromatic solvents with a high foam volume fraction up to 96% using Ultra-Turrax. The presence of biphenyl rings and short alkyl chains was crucial for foamability. Organic foams were prepared for aromatic solvents with intermediate surface tension (35–44 mN m −1 ) and contact angle in the range 32–53°. Biphenyl-bridged particles outperformed polytetrafluoroethylene and fluorinated surfactants in benzyl alcohol.
研究领域:
材料科学
·
界面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Long Yan,Jingjing Guan,Ning Wang,Zheng Wei,Zhisheng Xu,Guoqing Niu
To meet the environmental requirement of foam extinguishing agent, a novel fluorine-free surfactant named amino-terminated polyether modified silicone (ATPMS) was successfully synthesized, and then in combination with hydrocarbon surfactant prepared fluorine-free foam extinguishing agent. The study carefully investigated surface tension, foamability, foam stability and fire extinguishing performance of fluorine-free foam extinguishing agent. The results indicate that ATPMS has a low surface tension of 21.17 mN/m, which combined with hydrocarbon surfactant at the mass concentration ratio of 1:1 imparts high surface activity. The sodium lauryl ether sulfate (AES)/ATPMS system owes the optimal comprehensive performance with an initial foam height value of 85.8 mm, a surface tension value of 24.76 mN/m and a foam stability value (the ratio of foam height between initial foam and five-minute foam) of 64.0 % at critical micelle concentration ( CMC ), respectively. Fire suppression test shows that the obtained fluorine-free foam extinguishing agent is effective in fighting diesel pool fires. The firefighting efficiency of foam agent links to the mixing chamber structure of compressed air foam fire extinguishing system (CAFS). When the mixing chamber of CAFS has a recurrent segment length of 50 mm and the filled particle size of 10 mm, the firefighting efficiency of fluorine-free foam extinguishing agent is optimal with a fire extinguishing time of 33 s and a temperature drop rate of 6.49 °C/s.
研究领域:
材料科学
·
消防工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 45
·期 31
·13902-13908
·
IF 3.591
Leiyi Fan,Rui Wang,Qian Zhang,Shuaizhuo Liu,Ruijie He,Ruiyang Zhang,Min Shen,Xin Xiang,Ying Zhou
Discharge of oily sewage causes serious environmental pollution and waste of resources, which can be solved by the process of oil/water separation. Polyurethane foam is a kind of promising candidate material for oil/water separation. In this work, a series of hydrophobic/lipophilic polyurethane foams were prepared by the in situ self-foaming method. The as-prepared polyurethane foams exhibited abundant open pore structures, excellent stability and superior hydrophobicity/lipophilicity. Thus, the as-prepared polyurethane foams can selectively absorb various oils/organic solvents from static and dynamic oil/water mixtures. The maximum absorption capacity for pump oil was up to 75.0 g g−1, and the separation fluxes were 1.5 × 106 L m−3 h−1 and 3.0 × 105 L m−3 h−1 for layered and turbulent oil/water mixtures, respectively. Moreover, the as-prepared polyurethane foams can separate the oil-in-water emulsions with a separation efficiency of >99% and a separation flux of 2.7 × 105 L m−3 h−1. The large-scale preparation of hydrophobic polyurethane foams by this method confirmed their potential in practical applications.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Yongzhen Wang,Xiang Yu,Weiqiang Fan,Rulin Liu,Yuyan Liu
Oil spills threaten ecosystem and health seriously. Porous foams have been proved as ideal candidates for oil absorbents, however, many with poor oil retention (re-bleeding). Here, we creatively developed a composite foam oil absorbent capable of oil absorption and oil gelation , based on porous alginate foam and hydroxyl aluminum stearate oil gelator . The microstructure of alginate foam can be adjusted by the addition of t-butanol in the solvent, and long alkyl chains of gelator endow foam skeleton with good hydrophobicity , avoiding secondary pollution from traditional hydrophobic chemical modification. Interconnected skeleton decorated by oleophilic gelators contributes to high oil absorption. Oleophilic gelator can self-assemble into 3D network to entrap oils to form gels, giving rise to effective oil retention, realizing the integration of high oil absorption and oil retention. The natural abundant, low-cost composite foam would be promising for tackling oil spills.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 47
·26563-26570
·
IF 2.936
Zhicai He,Zhengping Zhao,Shengwei Xiao,Jintao Yang,Mingqiang Zhong
Polymeric microcellular foams with high strength and light weight are very important for industrial applications. However, regulating their cell structure and their weak flame retardancy are problematic. We designed single-arm POSS-based ionic liquids ([bel-POSS][PF6]), and constructed hybrid composites based on physical interaction between ionic liquids and carbon-based materials in PS microcellular foaming. Ionization of bel-POSS could result in a quaternary ammonium reaction and ion-exchange reaction, and the carbon materials exhibit good dispersion through blending. The prepared hybrid composites showed high CO2 adsorption. Conical calorimeter tests showed that PS composite materials could reduce the heat release rate, total heat release, toxic gases (CO2 and CO) release, and amount of smoke generated. These carbon materials could affect PS micropore structure, including the cell diameter and density. Upon addition of 5 wt% of carbon materials, the hole diameter decreased by >50%, and the hole density increased nearly ten folds.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CARBON
·
2019
·
IF 7.466
Jianwei Li,Yuanqing Ding,Ni Yu,Qiang Gao,Xun Fan,Xuan Wei,Guangcheng Zhang,Zhonglei Ma,Xinhai He
Carbon foams are obtained by pyrolysis of conventional polymeric porous materials usually show poor mechanical properties . The preparation of lightweight carbon foams with high mechanical strength and adjustable three-dimensional architecture still remains a huge challenge. This work reports an efficient approach for fabricating rigid carbon foams via carbonization of thermosetting polyimide foam. Benefiting from the cross-linked networks, the prepared carbon foams present excellent thermal and dimensional stability with low shrinkage of ∼47% after carbonized at 1500 °C. Moreover, the compressive strength of the carbon foams after carbonized at 1200 °C (CF-1200) reaches 0.25 MPa at 10% strains with the density of 0.091 g cm −3 . Notably, the CF-1200 shows superior electromagnetic interference (EMI) shielding effectiveness and specific EMI shielding effectiveness of ∼54 dB and 593.4 dB cm 3 /g respectively at 10 GHz with the thickness of 2.0 mm. In particular, the bulk density, mechanical properties, electrical conductivity of carbon foams can be adjusted by varying the characteristics of polyimide foam accordingly. As the result, these lightweight and stiff carbon foams with such superior EMI SE have great potential applications as structural-functional integrated materials in the aerospace and wireless telecommunication fields.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2022
·Vol. 308
·期 5
·2200559
·
IF 4.402
Lingcheng Meng,Jinling Zhang,Shuang Zhao,Desheng Qi,Pan Xu,Shuoqi Wu,Le Wang,Xigui Yue,Zhenhua Jiang
Polyaryletherketone is a kind of special engineering plastics with excellent comprehensive properties, high strength, good stability, and almost insoluble in any common solvent except concentrated sulfuric acid at room temperature. However, its high processing temperature also hinders its application and development in the foam. Here, a series of polyetheretherketone (PEEK) and diphenyl polyetheretherketone (PEDEK) composite foams are prepared by temperature induced phase separation, using diphenyl sulfone as solvent. The microstructure, thermal and mechanical properties of PEEK and PEDEK foam are compared. Highly porous PEEK and PEDEK foams with densities ranging from 0.13 to 0.25 g cm −3 , with compressive strength ranging from 0.68 to 2.6 MPa, respectively, are produced. Meanwhile, the introduction of diphenyl structure can effectively improve the performance of PEEK foams at high temperature. It is found that PEDEK foam has a higher operating temperature than PEEK, and the compressive strength of 0.24 g cm −3 foam is still ≈1 MPa at 200 °C.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2013
·Vol. 15
·期 8
·1-7
·
IF 2.175
Cui Hongtao,Zhao Yunan,Ren Wanzhong,Liu Yan,Wang Minmin
First aqueous non-silica foams, solely stabilized by CoOOH nanoparticles, were prepared by a new colloidal strategy. Highly water-soluble CoOOH nanoparticles with size of 1.5 nm were produced from the reaction between Co(OH) 2 nanosheets and ammonia. The foams were formed through the hand-shaking of the high-concentration colloid formed by the redisolving of CoOOH nanoparticles in water. The stability of the foams was attributed to the reduction of surface tension induced by the hydrophilic CoOOH particles and the support of particulate network in the void between bubbles. These two factors also provided resistance for the bubble collapse during the evaporation of solvent, resulting in the keeping of the original foam morphology after drying and the formation of a hierarchically hollow structure of CoOOH. Herein, we proved that the highly hydrophilic nanoparticles also can stabilize liquid foams. This conclusion is different from the classic theory on foams, which may provide new insight for foams and also a pathway for the preparation of inorganic hollow structure.
研究领域:
材料科学
·
纳米技术
·
胶体化学
·
结构功能材料
✓ 已验证
DOI
高影响因子
Thermal Science and Engineering Progress
·
2023
·
IF 4.8
Youjie Sheng,Yang Li,Li Ma,Canbin Yan,Yunchuan Peng,Xixi Liu
Foams stabilized by nanoparticles (NPs) and surfactants have a great research potential in the development of environment-friendly firefighting foams. In the present study, foam dispersions, consisting of hydrophilic SiO 2 NPs, a hydrocarbon surfactant (CAD-40), and a fluorocarbon surfactant (FS-50), were prepared to investigate the effect of NPs on the thermal stability of firefighting foams. The interactions between NPs and surfactants and foaming ability of the mixed dispersions were investigated. Foam decay, drainage, and coarsening under different thermal radiation intensities were systematically investigated. Results indicated that as the NP concentration was increased, the viscosity of the foam dispersions increased rapidly, the conductivity and foaming ability decreased, and the surface activity decreased initially and then increased. Foam volume decay, drainage, and coarsening under different temperatures were delayed by the NPs. As the concentration of NPs increased, the effect became more obvious. This study could provide theoretical guidance for the application of NPs in firefighting foams.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）