A unique behavior of water drops induced by low-density polyethylene surface with a sharp wettability transition

Lü, Xiaoying; Tan, Shuaixia; Zhao, Ning; Shen, Yang; Xu, Jie

doi:10.1016/j.jcis.2007.02.066

Cited by 10 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The difference between the advancing and receding angles (Dy ¼ y a Ày r ) is CAH, which provides the main resistance force. [19][20][21] In the present work, advancing and receding CA data indicate a contrasting CAH, which provides the main resistance force. [19][20][21] For instance, the CAH values at 20 and 30 1C were 101 and 141, respectively.…”

Section: Resultssupporting

confidence: 47%

See 1 more Smart Citation

Temperature-controlled directional spreading of water on a surface with high hysteresis

et al. 2013

View full text Add to dashboard Cite

The actuation of microscale liquid droplets is a key point in the lab-on-chip field. Marangoni force actuation resulting from a temperature gradient has remarkable advantages. However, high hysteresis between the droplet and the surface is an obstacle to this motion. Here, we take advantage of the temperature-responsive wettability of a surface made of a block copolymer (BCP) to show the temperature-controlled directional spreading of water droplets. By applying a temperature gradient on the BCP surface, both the topologies and chemical components in the nanodomains could be changed gradually. As a result, a wettability gradient force would form with the same direction as the Marangoni force, which could also be formed due to the same temperature gradient, and the collaborative effect of these forces could help overcome the high hysteresis. This was confirmed theoretically by calculating the total force acting on the droplet. The liquid droplet was observed to move by forces of non-mechanical origin in experiments conducted using a thermal gradient on the BCP films. Furthermore, two water droplets were observed to merge into one when they were placed in a V-shaped temperature field. These results help us understand the motion of droplets on a surface with high hysteresis and provide potential applications in microfluidic devices.

show abstract

Section: Resultssupporting

confidence: 47%

“…In actual experimental situations, this resistance force can be calculated from the CAH values. [19][20][21] The magnitude of the hysteresis force (F H ) is described as 29 F H ¼ 2Rgðcos y ro À cos y ao Þ ð 3Þ…”

Section: Resultsmentioning

confidence: 99%

Temperature-controlled directional spreading of water on a surface with high hysteresis

et al. 2013

View full text Add to dashboard Cite

show abstract

“…However, CAs were immediately reduced to 118.4-135.9°(with decreasing order of the S/W ratio) under a small stimulus such as a mechanical loading and vibration or sometimes without any external perturbation, suggesting that the Wenzel state is more stable than the Cassie state. The Cassie to Wenzel transition on microstructured surfaces has been reported both experimentally and theoretically [1,[26][27][28][29].…”

Section: Fabrication Of Dual-scale Hierarchical Structuresmentioning

confidence: 95%

Wettability of nanoengineered dual-roughness surfaces fabricated by UV-assisted capillary force lithography

Jeong

Kwak

Park

et al. 2009

Journal of Colloid and Interface Science

104

View full text Add to dashboard Cite

“…Polypropylene (PP), which is a cheap polyolefin, was transformed into a superhydrophobic surface for the first time by using a simple solvent/nonsolvent phase separation method by Erbil et al in 2003 5. Later, Lu et al applied the same phase separation method to obtain superhydrophobic surfaces from low‐density polyethylene (LDPE) 6–8. Similarly, Kang et al formed superhydrophobic LDPE surfaces having porous micro–nano binary morphology structures by using a simple casting method 9.…”

Section: Introductionmentioning

confidence: 99%

Combined XPS and contact angle studies of flat and rough ethylene‐vinyl acetate copolymer films

Doğancı¹,

Cansoy²,

Ucar³

et al. 2011

J of Applied Polymer Sci

View full text Add to dashboard Cite

Flat and rough thin films were prepared by dip coating using LDPE, PVAc, and EVA polymers containing 12-40% VA contents. Surface free energy of flat films was determined by measuring contact angles. Surface atomic composition was investigated by XPS at 0 and 60 take-off angles. XPS results show that hydrophobic PE component was found to enrich at the near-surface region for all EVA samples for a depth of $ 5 nm for both flat and rough surfaces, whereas hydrophilic VA component was enriched on the surface when VA < 18% for only at 10 nm depth. The difference between the XPS results of the flat and rough surfaces was not significant for EVA samples except EVA-33 surface where the atomic oxygen content decreased 15-20% for rough surfaces. Contact angle hysteresis values for the rough samples were much larger than that of the flat samples for LDPE and EVA-12 surfaces due to the presence of partial trapping of air pockets on these rough surfaces. A good agreement was obtained between surface concentration of atomic oxygen in the 5 nm outermost layer and c À S surface free energy component especially for the samples having high VA contents.

show abstract

A unique behavior of water drops induced by low-density polyethylene surface with a sharp wettability transition

Cited by 10 publications

References 34 publications

Temperature-controlled directional spreading of water on a surface with high hysteresis

Temperature-controlled directional spreading of water on a surface with high hysteresis

Wettability of nanoengineered dual-roughness surfaces fabricated by UV-assisted capillary force lithography

Combined XPS and contact angle studies of flat and rough ethylene‐vinyl acetate copolymer films

Contact Info

Product

Resources

About