Nanoporous Polymer Films from Immiscible Polymer Blends: Pore Size and Composition Dependence

ABSTRACTNanoporous polymer films have been prepared using immiscible blends of polyetherimide (PEI) and poly(caprolactone diol) (PCLD). The films were prepared by spin-coating from a common solvent — dichloromethane (DCM). To create the nanoporous films, PCLD was removed by immersing the films in acetone, which dissolves PCLD only. Field emission scanning electron microscopy was used to study the porous structure. The pore structure of the films was affected by many factors such as composition of the blend, molecular weight, and various processing parameters. The formation of nanometer size pores was mainly due to the fast phase separation process during spin-coating. The pore size and pore size distribution was found to depend on the blend composition.

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Binary Self-Assembly of Nanocolloidal Arrays using Concurrent and Sequential Spin Coating Techniques

Materials ◽

10.3390/ma14020274 ◽

2021 ◽

Vol 14 (2) ◽

pp. 274

Author(s):

Shih-Jyun Shen ◽

Demei Lee ◽

Yu-Chen Wu ◽

Shih-Jung Liu

Keyword(s):

Silicon Substrate ◽

Self Assembly ◽

Spin Coating ◽

Processing Parameters ◽

The Self ◽

Silicon Substrates ◽

Processing Conditions ◽

Polystyrene Spheres ◽

Optimal Processing ◽

Spin Coater

This paper reports the binary colloid assembly of nanospheres using spin coating techniques. Polystyrene spheres with sizes of 900 and 100 nm were assembled on top of silicon substrates utilizing a spin coater. Two different spin coating processes, namely concurrent and sequential coatings, were employed. For the concurrent spin coating, 900 and 100 nm colloidal nanospheres of latex were first mixed and then simultaneously spin coated onto the silicon substrate. On the other hand, the sequential coating process first created a monolayer of a 900 nm nanosphere array on the silicon substrate, followed by the spin coating of another layer of a 100 nm colloidal array on top of the 900 nm array. The influence of the processing parameters, including the type of surfactant, spin speed, and spin time, on the self-assembly of the binary colloidal array were explored. The empirical outcomes show that by employing the optimal processing conditions, binary colloidal arrays can be achieved by both the concurrent and sequential spin coating processes.

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Selective porous gates made from colloidal silica nanoparticles

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.215 ◽

2015 ◽

Vol 6 ◽

pp. 2105-2112 ◽

Cited By ~ 9

Author(s):

Roberto Nisticò ◽

Paola Avetta ◽

Paola Calza ◽

Debora Fabbri ◽

Giuliana Magnacca ◽

...

Keyword(s):

Silica Nanoparticles ◽

Spin Coating ◽

Colloidal Silica ◽

Sol Gel ◽

Chemical Species ◽

Solvent System ◽

Porous Films ◽

Nanoporous Films ◽

Poly Ethylene Oxide ◽

Poly Ethylene

Highly selective porous films were prepared by spin-coating deposition of colloidal silica nanoparticles on an appropriate macroporous substrate. Silica nanoparticles very homogenous in size were obtained by sol–gel reaction of a metal oxide silica precursor, tetraethyl orthosilicate (TEOS), and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as soft-templating agents. Nanoparticles synthesis was carried out in a mixed solvent system. After spin-coating onto a macroporous silicon nitride support, silica nanoparticles were calcined under controlled conditions. An organized nanoporous layer was obtained characterized by a depth filter-like structure with internal porosity due to interparticle voids. Permeability and size-selectivity were studied by monitoring the diffusion of probe molecules under standard conditions and under the application of an external stimulus (i.e., electric field). Promising results were obtained, suggesting possible applications of these nanoporous films as selective gates for controlled transport of chemical species in solution.

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Nanoporous Films with Sub-10 nm in Pore Size from Acid-Cleavable Block Copolymers

Macromolecular Rapid Communications ◽

10.1002/marc.201600662 ◽

2017 ◽

Vol 38 (5) ◽

pp. 1600662 ◽

Cited By ~ 4

Author(s):

Yayuan Li ◽

Yawei Xu ◽

Shubo Cao ◽

Yongbin Zhao ◽

Ting Qu ◽

...

Keyword(s):

Block Copolymers ◽

Pore Size ◽

Nanoporous Films

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Effects of particle size, concentration and pore size on the loading density of silica nanoparticle monolayer arrays on anodic aluminum oxide substrates prepared by the spin-coating method

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2021.125465 ◽

2021 ◽

pp. 125465

Author(s):

Kazutoshi Sekiguchi ◽

Ken-ichi Katsumata ◽

Hiroyo Segawa ◽

Takayuki Nakanishi ◽

Atsuo Yasumori

Keyword(s):

Particle Size ◽

Aluminum Oxide ◽

Pore Size ◽

Spin Coating ◽

Anodic Aluminum Oxide ◽

Silica Nanoparticle ◽

Spin Coating Method ◽

Anodic Aluminum ◽

Oxide Substrates ◽

Coating Method

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Improving the barrier character of poly(caprolactone): Transport properties and free volume of immiscible blends

Journal of Applied Polymer Science ◽

10.1002/app.48018 ◽

2019 ◽

Vol 136 (40) ◽

pp. 48018 ◽

Cited By ~ 3

Author(s):

Sorkunde Eceolaza ◽

Ainara Sangroniz ◽

Javier Río ◽

Marian Iriarte ◽

Agustin Etxeberria

Keyword(s):

Transport Properties ◽

Free Volume ◽

Immiscible Blends ◽

Poly Caprolactone

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Effect of Pore Size of Self-Organized Honeycomb-Patterned Polymer Films on Spreading, Focal Adhesion, Proliferation, and Function of Endothelial Cells

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.514 ◽

2007 ◽

Vol 7 (3) ◽

pp. 763-772 ◽

Cited By ~ 65

Author(s):

Masaru Tanaka ◽

Aiko Takayama ◽

Emiko Ito ◽

Hiroshi Sunami ◽

Sadaaki Yamamoto ◽

...

Keyword(s):

Endothelial Cells ◽

Pore Size ◽

Focal Adhesion ◽

Polymer Films ◽

Self Organized ◽

And Function

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Electrical, Mechanical, and Structural Properties of Fluoro-Containing Poly(silsesquioxanes) Based Porous Low k Thin Films

MRS Proceedings ◽

10.1557/proc-766-e8.3 ◽

2003 ◽

Vol 766 ◽

Author(s):

Jingyu Hyeon-Lee ◽

Jihoon Rhee ◽

Jungbae Kim ◽

Jin-Heong Yim ◽

Seok Chang

Keyword(s):

Thin Films ◽

Pore Size ◽

Dielectric Constants ◽

Commercial Application ◽

Porous Films ◽

Low Dielectric ◽

Nanoporous Films ◽

Positronium Annihilation ◽

Positronium Annihilation Lifetime Spectroscopy ◽

Low K

AbstractLow dielectric fluoro-containing poly(silsesquioxanes) (PSSQs) have been synthesized using trifluoropropyl trimethoxysilane (TFPTMS), methyl trimethoxysilane (MTMS), and 2, 4, 6, 8-tetramethyl-2, 4, 6, 8-tetra(trimethoxysilylethyl) cyclotetrasiloxane. The properties of fluorocontaining PSSQs based thin films were studied by electrical, mechanical, and structural characterization. Film was spun on a silicon substrate, baked at 150°C and 250°C for 1 minute, respectively, and cured in the furnace at 420°C for 1 hour under vacuum condition. Thermally decomposable trifluoropropyl groups of the fluoro-containing PSSQ were served as a pore generator and partially contributed to lower a dielectric constant. â-cyclodextrin (CD) was also employed as a pore generator. The concentration of the pore generator in the film was varied from 0 to 30 %. The dielectric constants of the porous PSSQ films were found to be in the range of 2.7 – 1.9 (at 100 kHz). Hardness and Young's modulus of the films were measured by nano-indentation. The elastic modulus and hardness of the porous films were well correlated with the concentration of the pore generators. Positronium Annihilation Lifetime Spectroscopy (PALS) was employed to characterize a pore size of the porous fluoro-containing PSSQ film. The pore size of the film was less than 2.2 nm. The nanoporous films showed quite promising properties for commercial application.

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Research on Side-Insulation of Tool Electrode for Micro Electrochemical Machining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.60-61.380 ◽

2009 ◽

Vol 60-61 ◽

pp. 380-387 ◽

Cited By ~ 9

Author(s):

Gai Hong Liu ◽

Yong Li ◽

Xu Peng Chen ◽

Shan Jin Lv

Keyword(s):

Spin Coating ◽

Electrochemical Machining ◽

Processing Parameters ◽

Machining Accuracy ◽

Tool Electrode ◽

Insulation Material ◽

Durability Test ◽

Micro Ecm ◽

Micro Tool ◽

Micro Array

In micro electrochemical machining (micro ECM), side-insulation of tool electrode can significantly improve the machining accuracy, especially for high aspect ratio structures. This paper presented a new side-insulation approach for not only micro single electrodes but also micro array electrodes, in which spin-coating and room curing are used to coat the micro tool electrodes with a very thin film of polymer, followed by an end-rubbing process to remove the insulation material from the electrode end surfaces. Processing parameters of spin-coating were optimized experimentally, and side-insulated micro single electrodes with a double-layer epoxy coating of 3m thickness were prepared. Experiments were made to test the performance of the side-insulation film under simulated micro ECM conditions. And the results demonstrated good insulativity and high adherence strength in a 6-hour durability test. Also side-insulation for micro array electrodes was performed using this approach.

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