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75095011501350Wavelength / cm-1
Ab
sorb
ance
-Si-O-Si-
Si-OH
Si-CH3
Supporting Information for Manuscript Entitled with
Liquid Marbles Supported by Monodisperse
Poly(methylsilsesquioxane) Particles
by Shigesaburo Ogawa, Hirohmi Watanabe, Liming Wang, Hiroshi Jinnai, Thomas J.
McCarthy, and Atsushi Takahara*
e-mail: [email protected]
This supporting information contains (1) characterization of PMSQ particles, (2) liquid
marble formation, (3) the effect of surface cleaning, (4) confocal laser scanning
microscopy observation, (5) calculation of number of particulate layer of water liquid
marble, (6) effective surface tension of water marble, (7) evaporation of water inside
liquid marble, and (8) LB film properties.
1. Characterization of PMSQ particles.
FT-IR spectrum of PMSQ particles showed a very small absorption band attributed to
Si-OH vibration at around 920 cm-1
, indicating that little residual silanol is present.
Figure S1. FT-IR spectrum of PMSQ particle
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2. Liquid marble formation.
Table S1 Digital Photograph of PMSQ Liquid Marbles with Different Liquids.
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3. The effect of surface cleaning.
Table S2 Optical Microscopic Images of Liquid Marble Surfaces Before and After
Surface Cleaning.
* Liquid marble was broken during the surface cleaning process.
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4. CLSM observation.
Figure S2. CLSM observation of an EmimTFB liquid marble at different heights.
Observance position depicted by colour lines in z axis was changed from (a) bottom
side to (d) top side.
Figure S3. CLSM images of bottom area of liquid marble. 5 µl of (a) water containing
1.0 mg/ml rhodamine B dye, (b) glycerol containing saturated rhodamine B dye and (c)
EmimMS containing 0.1 mgml rhodamine B dye.
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5. Calculation of number of particulate layer of water liquid marble.
Figure S4. Weight loss of 5 µl of water liquid marble as a function of elapsed time.
Inset shows the enlarged view.
Figure S5. Schematic representations of (a) surface area of a liquid marble and (b)
combined surface area of a PMSQ particle and two pores in HCP structure. *1 and *2
were obtained by the optical microscopy. *3 was obtained by SEM observation. *4 was
used as the reference data.[S5]
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0 5 10 15 20Time / min
Weight / mg
WPMSQ particle
Water evaporation
0
0.1
0.2
5 10 15
Time / min
Weight / mg
H
R
A: 2R-H
r
W: weight
N: number of particles
S: surface area
H: Height of liquid marble = 1.96 mm*2
R: Radius of liquid marble = 1.11 mm*1
r: Radius of PMSQ particle = 2.2 µm*3
d: True specific gravity = 1.32 g/cm3 *4
a b
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6. Effective surface tension of water marble.
The effective surface tension (γeff) of the water marble was evaluated by the puddle
height of large marbles. The γeff can be calculated by the equation,
���� � ����
��� ��� �� � (1)
where ρ is the liquid density (1.00 g/cm3 for water), g is gravitational constant, h is
maximal marble heights, and θLM is the apparent contact angle of the liquid on the
substrate. h and θLM were obtained from the optical images of water marbles with
puddle shape using liquid (Figure S6). Note that the γeff was determined using a surface
'uncleaned' water marble because of the difficulty of the handling of 'cleaned' liquid
marble at large volume. We assumed that the cleaning process does not affect on γeff
value because exess adsorped partices were intact with the internal liquid.
Figure S6. Height and contact angle of water marbles containing various volumes of
water. Inset show the optical image of 300 µl water marble.
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7. Evaporation of water inside liquid marble. The change in mass of liquid marble
was measured to determine the evaporation rate of the internal liquid according to our
previous report.[S6]
The surface cleaned liquid marbles were kept under static conditions
on OTS substrate, and the mass change was monitored by a precision balance.
Evaporation behaviors of bare water on Si (111) and OTS substrates were also
investigated under same condition.
As shown in Figure S7, water on Si (111) showed short-term stability less than 25
min for 5 µL water droplet. On the other hand, evaporation of a 5 µL water droplet took
place within 35 min on OTS substrate, while it took ca. 31 min after encapsulating as a
liquid marble. It was clear that the high contact angle is important for the prevention of
water evaporation, but the encapsulation by PMSQ monolayer did not show significant
effect.
Figure S7. Weight loss percentage as a function of elapsed time of a liquid marble
(circle), and water on Si(111) (diamond), and on OTS substrate (triangle).
0
10
20
30
40
50
60
70
80
90
100
0 500 1000 1500 2000 2500
Water marble
Water on Si(111)
Water on OTS substrate
Time / s
Weight%
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8. Film Properties.
Table S3 Physical Properties of PMMA and OTS-Modified Substrates.
Thickness / nm Water contact angle / °
PMMA 193 66.4
OTS 3.3 108.4
Figure S8. Optical microscopic image of LB film of PMSQ particulate layer on PMMA
spin-casted film (PMSQ/PMMA).
3. References.
[S1] Fowkes, F. M.; Riddle Jr., F. L.; Pastore, W. E.; Weber, A. A., Colloids Surf.
1990, 43, 367-387.
[S2] Jańczuk, B.; Wójcik, W.; Zdziennicka, A. J. Colloids Interface Sci. 1993, 157,
384-393.
[S3] Tariq, M.; Freire, M. G.; Saramago, B.; Coutinho, J. A. P.; Lopes, J. N. C.;
Rebelo, L. P., Chem. Soc. Rev. 2012, 41, 829-868.
[S4] Jasper, J. J., J. Phys. Chem. Ref. Data 1972, 1, 841-1009.
[S5] http://www.itschem.com/TDS/TOSPEARL2000B.pdf
[S6] Matsukuma, D.; Watanabe, H.; Minn, M.; Fujimoto, A.; Shinohara, T.; Jinnai, H.;
Takahara, A., RSC Adv. 2013, 3, 7862-7866.