Pattern-directed to isotropic dewetting transition in polymer films on micropatterned surfaces with differential surface energy contrast

Soft Matter ◽  
2007 ◽  
Vol 3 (5) ◽  
pp. 613 ◽  
Author(s):  
Duangrut Julthongpiput ◽  
Wenhua Zhang ◽  
Jack F. Douglas ◽  
Alamgir Karim ◽  
Michael J. Fasolka
Keyword(s):  
Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 736
Author(s):  
Kyutae Seo ◽  
Hyo Kang

We synthesized a series of polystyrene derivatives that were modified with precursors of liquid crystal (LC) molecules, such as 4-ethyloxyphenol (homopolymer PEOP and copolymer PEOP#; # = 20, 40, 60, and 80, where # indicates the molar fraction of 4-ethyloxyphenoxymethyl in the side chain), 4-n-butyloxyphenol (PBOP), 4-n-hexyloxyphenol (PHOP), and 4-n-octyloxyphenol (POOP), via polymer modification reaction to investigate the orientation of LC molecules on polymer films, exhibiting part of the LC molecular structure. LC molecules showed a stable and uniform vertical orientation in LC cells fabricated with polymers that have 4-ethyloxyphenoxymethyl in the range of 40–100 mol%. In addition, similar results were obtained in LC cells fabricated with homopolymers of PEOP, PBOP, PHOP, and POOP. The vertical orientation of LC molecules in LC cells fabricated with polymer films correlated to the surface energy of polymer films. For example, vertical LC orientation was observed when the total surface energies of the polymer films were lower than approximately 43.2 mJ/m2. Good alignment stabilities were observed at 150 °C and 20 J/cm2 of ultraviolet irradiation for LC cells fabricated with PEOP film.


2014 ◽  
Vol 140 (12) ◽  
pp. 124902 ◽  
Author(s):  
A. C. C. Esteves ◽  
K. Lyakhova ◽  
J. M. van Riel ◽  
L. G. J. van der Ven ◽  
R. A. T. M. van Benthem ◽  
...  

2014 ◽  
Vol 52 (18) ◽  
pp. 1195-1202 ◽  
Author(s):  
Chae Bin Kim ◽  
Dustin W. Janes ◽  
Dana L. McGuffin ◽  
Christopher J. Ellison

1998 ◽  
Vol 517 ◽  
Author(s):  
G.W. Tyndall ◽  
R.J. Waltman

AbstractSurface energies of molecularly-thin, perfluoropolyether (PFPE)-lubricated, amorphous carbon surfaces are presented as a function of the applied PFPE structure and thickness. A framework is developed to aid in the interpretation of the surface energy data. Information regarding the structure of these PFPE films adsorbed on CHx at the monolayer thickness levels is elucidated. Evidence for ordering in these polymer films is presented and interpreted to result from a combination of both, lateral cohesive interactions within the plane of the monolayer, and adhesive interactions between the PFPE monolayer and the underlying substrate.


2020 ◽  
Vol 8 (27) ◽  
pp. 13600-13609 ◽  
Author(s):  
Xin Guan ◽  
Erol Yildirim ◽  
Zeng Fan ◽  
Wanheng Lu ◽  
Bichen Li ◽  
...  

Coating with Rhodamine 101 can significantly enhance the Seebeck coefficient of PEDOT:PSS, and surface energy filtering is proposed to be the reason for this effect.


Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 281 ◽  
Author(s):  
Changha Ju ◽  
Shinwoo Kang ◽  
Taehyung Kim ◽  
Chanhyuk Park ◽  
Hyo Kang

We investigated the liquid crystal (LC) alignment behaviors of butyl hydroxybenzoate-substituted polystyrene (PBHB#; # = 20, 40, 60, 80, and 100, where # indicates the molar fraction of butyl hydroxybenzoate in the side chain), methyl hydroxybenzoate-substituted polystyrene (PMHB100), and ethyl hydroxybenzoate-substituted polystyrene (PEHB100). Generally, LC cells made employing polymer films having longer alkyl groups in the side chain show vertical LC alignment. For instance, a LC cell fabricated with the PMHB100 film showed random planar LC alignment, while the LC cells made from the PEHB100 and PBHB100 films exhibited vertical LC alignment. Moreover, LC cells prepared from a polymer film having a higher molar content of butyl hydroxybenzoate in the side chain exhibited vertical LC alignment. The observed vertical LC alignment behaviors are closely related to the surface energy of these polymer films. For instance, vertical LC alignment was observed when the surface energy of the polymer film was less than ~43.86 mJ/m2, which could result from the nonpolar alkyl groups of the alkyl hydroxybenzoate moiety. The LC cell prepared from PBHB100 as the LC alignment layer showed good electro-optical characteristics such as voltage holding ratio, residual DC voltage, and alignment stability at 200 °C.


Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2822
Author(s):  
DaEun Yang ◽  
Kyutae Seo ◽  
Hyo Kang

We synthesized a series of polystyrene derivatives containing various side groups, such as the 4-(tert-butyl)-phenoxymethyl, 3-(tert-butyl)-phenoxymethyl, 2-(tert-butyl)-phenoxymethyl, 4-cumyl-phenoxymethyl, and 4-trityl-phenoxymethyl groups, through a polymer modification reaction to examine the liquid crystal (LC) alignment of these derivatives. In general, the vertical LC alignment on polymer films can be affected by the position and structure of the terminal moiety of the polymer side group. For example, the LC cells fabricated with 4-(tert-butyl)-phenoxymethyl-substituted polystyrene having a tert-butyl moiety as a para-type attachment to the phenoxy groups of the polystyrene derivatives exhibited vertical LC alignment, whereas the LC cells prepared from 3-(tert-butyl)- and 2-(tert-butyl)-phenoxymethyl-substituted polystyrene films exhibited planar LC alignment. In addition, the LC cells fabricated from 4-cumyl- and 4-trityl-phenoxymethyl-substituted polystyrene films with additional phenyl rings in the side groups exhibited planar LC alignment, in contrast to the LC alignment of the (tert-butyl)-phenoxymethyl-substituted polystyrene series. The vertical LC orientation was well correlated with the surface energy of these polymer films. For example, vertical LC orientation, which mainly originates due to the nonpolar tertiary carbon moiety having bulky groups, was observed when the surface energy of the polymer was lower than 36.6 mJ/m2.


Author(s):  
Kseniya A. Korsakova ◽  
◽  
Elena A. Novozhilova ◽  
Anatoliy A. Malygin ◽  
◽  
...  

Composite materials based on polypropylene and polytetrafluoroethylene modified with mono- and two-component elementoxide (elements - phosphorus (5+), vanadium (5+), titanium (4+)) structures were synthesized. The influence of the chemical nature and the sequence of grafting (in two-component systems) of modifier elements on the wettability of polymer films, energy characteristics and morphology of their surface was established


2000 ◽  
Vol 12 (7) ◽  
pp. 2031-2038 ◽  
Author(s):  
S. R. Coulson ◽  
I. S. Woodward ◽  
J. P. S. Badyal ◽  
S. A. Brewer ◽  
C. Willis

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