COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Heng Li,Yafeng Zhang,Xing Shi Gu,Huimin Qi,Jiaxin Yu,Jian Zhuang
The variation of velocity field inside a droplet was investigated by particle image velocimetry when the droplet moved on a superhydrophobic surface. Results showed that shear stress increased with the increase of the motion velocity of droplet and droplet viscosity when the motion velocity of droplet increased from 0.3 to 1.1 mm/s and the droplet viscosity increased from 2.69 to 17.41 mPa·s. Moreover, friction force at liquid/solid interface was independent on droplet volume, viscosity and motion velocity on the superhydrophobic surface. It is indicated that the variation of velocity field and shear stress inside droplet was closely associated with the change of the influence depth and the center of mass inside the droplet caused by the substrate. The findings are helpful to understand the motion behaviors of a droplet on the superhydrophobic surface to reduce the energy dissipation when a droplet transport on the superhydrophobic surfaces.
研究领域:
物理学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Junjie Yang,Lei Liu
The friction influence of 2-D molybdenum disulfide (MoS 2 ) films deposited on different substrates (Si, SiO 2 and Al 2 O 3 ) by atomic layer deposition (ALD) has been investigated. All of the three substrates showed a trend of decreasing friction with increasing number of layers of MoS 2 , but the friction leveled off for more than 6 layers samples. Comparing these 2-D MoS 2 films with each other, MoS 2 on the Al 2 O 3 possesses the lowest friction, while MoS 2 on the Si possesses the highest one, owing to effect of substrate on the specific self-limiting reaction in ALD process. At the same time, the friction of the monolayer MoS 2 is strongest affected by sulfur deficient. As the number of layers increases, the influence of the substrate on the friction of MoS 2 can be approximately characterized by the work of adhesion. Greater work of adhesion corresponds to a higher friction force. When the thickness is more than 6 layers, the substrate effect disappears gradually. Moreover, the friction of 2-D MoS 2 could be controlled near linearly by changing plasma treatment time within the range from 1 to 20 s, which suggests a possible way for the friction control of 2-D MoS 2 on different substrate quasi-qualitatively or even qualitatively.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Xiaobing Wang,Lujie Wang,Yi Zhou,Ying Lu,Jing Liu,Lanyan Zhu,Zhao Ding,Yang Zhou
This study presents a novel method for fabricating surface-engineered caterpillar-like silica nanocomposites by combining rod-like nanorods with spherical nanoparticles to control aspect ratios and surface functionalization. This unique design facilitates functional assembly at the nanoscale. Additionally, we developed an innovative composite by encapsulating polyurethane elastomers within shear thickening fluid (STF)-impregnated Kevlar, significantly enhancing the flexibility and durability of the resulting STF/Kevlar/PU composite. Microstructural and chemical modifications were characterized, and detailed rheological analysis revealed a 165 % increase in viscosity and a substantial rise in storage modulus from 91.56 to 18,640 Pa, indicating improved surface morphology and roughness. These enhancements promoted stronger interparticle friction and rotational motion during flow. Impact resistance tests further demonstrated a 314 % increase in peak impact force, driven by frictional interactions between the dispersed caterpillar-like particles. The results confirmed that surface roughness and adhesive forces play a critical role in activating stress-dependent frictional contacts, a key mechanism behind the improved performance. These findings highlight the potential of these composites for mitigating penetration injuries and offer precise control over the shear-thickening transition in engineering applications, making them promising candidates for lightweight protective materials.
研究领域:
材料科学
·
纳米技术
·
力学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2021
·
IF 9.078
Shutian Liu,Conglin Dong,Chengqing Yuan,Xiuqin Bai,Ye Tian,Guoliang Zhang
Stabilizing friction force of polymer composites’ wear interfaces during frictional processes is useful to suppress or eliminate the friction-induced chatter and noise behaviors in low velocity. A new Polyimide (PI) matrix composite material composed of Polyimide and MoS 2 nano particles was fabricated and tested. The experimental wear tests were conducted to investigate relationship between friction forces, friction-induced chatters and noises under dry and water conditions in low friction velocity . The typical tribological properties of modified composite and some typical mechanical properties were analyzed to reveal the mechanism of MoS 2 nano particles on frictional behaviors reduction. The results showed that the transformations and formations of MoS 2 tribo-film presented excellent COF reduction on modified PI composite by more than 50%, and also could effectively reduce PI deformations on wear surface which obviously decreased friction forces and their fluctuating amplitudes. These cases endowed the modified PI composite excellent performances on friction-induced chatter and noise reductions compared to the pure PI even though some mechanical properties were weakened. The understanding gained herein is helpful for comprehending the friction-induced chatter reduction of the MoS 2 filler on polymer matrix composites and future designing of polymer matrix composites with low friction and good chatter and noise reductions in low friction velocity.
研究领域:
材料科学
·
摩擦学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-9
·
IF 17.694
Fang Bo,Yan Jianmin,Chang Dan,Piao Jinli,Ma Kit Ming,Gu Qiao,Gao Ping,Chai Yang,Tao Xiaoming
The development of continuous conducting polymer fibres is essential for applications ranging from advanced fibrous devices to frontier fabric electronics. The use of continuous conducting polymer fibres requires a small diameter to maximize their electroactive surface, microstructural orientation, and mechanical strength. However, regularly used wet spinning techniques have rarely achieved this goal due primarily to the insufficient slenderization of rapidly solidified conducting polymer molecules in poor solvents. Here we report a good solvent exchange strategy to wet spin the ultrafine polyaniline fibres. The slow diffusion between good solvents distinctly decreases the viscosity of protofibers, which undergo an impressive drawing ratio. The continuously collected polyaniline fibres have a previously unattained diameter below 5 µm, high energy and charge storage capacities, and favorable mechanical performance. We demonstrated an ultrathin all-solid organic electrochemical transistor based on ultrafine polyaniline fibres, which operated as a tactile sensor detecting pressure and friction forces at different levels.
研究领域:
材料科学
·
电子工程
·
高分子科学
·
纳米技术
✓ 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）