Limits...
Bioinspired polymer microstructures for directional transport of oily liquids

View Article: PubMed Central - PubMed

ABSTRACT

Nature has always served as an inspiration for scientists, helping them to solve a large diversity of technical problems. In our case, we are interested in the directional transport of oily liquids and as a model for this application we used the flat bug Dysodius lunatus. In this report, we present arrays of drops looking like polymer microstructures produced by the two-photon polymerization technique that mimic the micro-ornamentation from the bug's cuticle. A good directionality of oil transport was achieved, directly controlled by the direction of the pointed microstructures at the surface. If the tips of the drop-like microstructures are pointing towards the left side, the liquid front moves to the right and vice versa. Similar effects could be expected for the transport of oily lubricants. These results could, therefore, be interesting for applications in friction and wear reduction.

No MeSH data available.


Related in: MedlinePlus

Two-photon lithography set-up (40× = objective lens magnification, NA = numerical aperture of the objective lens, M = telescope magnification, PH = pinhole, CCD = charge-coupled device camera, APD = avalanche photodiode, PC = personal computer).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5383830&req=5

RSOS160849F2: Two-photon lithography set-up (40× = objective lens magnification, NA = numerical aperture of the objective lens, M = telescope magnification, PH = pinhole, CCD = charge-coupled device camera, APD = avalanche photodiode, PC = personal computer).

Mentions: For the fabrication of periodic drop-like microstructures a two-photon polymerization set-up was used [16], as shown in figure 2. The beam of a Ti-sapphire femtosecond laser (Mai Tai, Spectra Physics, 800 nm, 150 fs, 800 MHz) is first mode-cleaned by a 30 µm pinhole (PH), expanded by means of a telescope with a magnification M = 1 : 3, and then focused on a glass slide surface by a 40× magnification Olympus objective lens that has a numerical aperture of 0.6. An adjustment ring on the objective lens compensates for the refractive index mismatch between the glass slide and the photoresist. The backscattered light from the glass slide passes through the second dichroic mirror in front of the objective lens and is focused into an avalanche photodiode (APD). Together with the piezo-actuator scanning stages (scan range 1500 × 1500 × 250 µm) and a personal computer (PC), the APD is part of a confocal microscope used to determine the precise position of the air–glass interface, i.e. the starting point of structure-writing. The microstructures were written on a glass substrate (24 × 50 mm2) at a speed of 30 µm s−1, with a laser excitation power of 21 mW.Figure 2.


Bioinspired polymer microstructures for directional transport of oily liquids
Two-photon lithography set-up (40× = objective lens magnification, NA = numerical aperture of the objective lens, M = telescope magnification, PH = pinhole, CCD = charge-coupled device camera, APD = avalanche photodiode, PC = personal computer).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5383830&req=5

RSOS160849F2: Two-photon lithography set-up (40× = objective lens magnification, NA = numerical aperture of the objective lens, M = telescope magnification, PH = pinhole, CCD = charge-coupled device camera, APD = avalanche photodiode, PC = personal computer).
Mentions: For the fabrication of periodic drop-like microstructures a two-photon polymerization set-up was used [16], as shown in figure 2. The beam of a Ti-sapphire femtosecond laser (Mai Tai, Spectra Physics, 800 nm, 150 fs, 800 MHz) is first mode-cleaned by a 30 µm pinhole (PH), expanded by means of a telescope with a magnification M = 1 : 3, and then focused on a glass slide surface by a 40× magnification Olympus objective lens that has a numerical aperture of 0.6. An adjustment ring on the objective lens compensates for the refractive index mismatch between the glass slide and the photoresist. The backscattered light from the glass slide passes through the second dichroic mirror in front of the objective lens and is focused into an avalanche photodiode (APD). Together with the piezo-actuator scanning stages (scan range 1500 × 1500 × 250 µm) and a personal computer (PC), the APD is part of a confocal microscope used to determine the precise position of the air–glass interface, i.e. the starting point of structure-writing. The microstructures were written on a glass substrate (24 × 50 mm2) at a speed of 30 µm s−1, with a laser excitation power of 21 mW.Figure 2.

View Article: PubMed Central - PubMed

ABSTRACT

Nature has always served as an inspiration for scientists, helping them to solve a large diversity of technical problems. In our case, we are interested in the directional transport of oily liquids and as a model for this application we used the flat bug Dysodius lunatus. In this report, we present arrays of drops looking like polymer microstructures produced by the two-photon polymerization technique that mimic the micro-ornamentation from the bug's cuticle. A good directionality of oil transport was achieved, directly controlled by the direction of the pointed microstructures at the surface. If the tips of the drop-like microstructures are pointing towards the left side, the liquid front moves to the right and vice versa. Similar effects could be expected for the transport of oily lubricants. These results could, therefore, be interesting for applications in friction and wear reduction.

No MeSH data available.


Related in: MedlinePlus