A Polymer Thin-Film Technique to Study Phase Separation

There is a great deal of interest in the morphology of polymers. Polymer systems such as physical blends, copolymers and latexes of the core-shell type have become increasingly important in “designing properties”. of the final polymer. Phase separation examination is an excellent method of studying the morphology in these polymer systems.Normally phase separation in polymers has been studied by TEM. The standard sample preparation is to embed the solid polymer in epoxy and then microtome. Microtoming can create artifacts such as distortion due to the knife, cutting difficulty with a rubber phase and possible polymer-epoxy interaction. Because of the above mentioned problems a thin film technique has been developed to circumvent the microtoming procedure. A ruthenium tetrox-ide (RUO4) stain was also used to increase contrast.

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A Study on Suitability of II-VI Semiconductor / Solid Polymer Thin Film Junctions for Photovoltaic Application

Materials Today Proceedings ◽

10.1016/j.matpr.2016.07.002 ◽

2016 ◽

Vol 3 (9) ◽

pp. 2832-2840 ◽

Cited By ~ 2

Author(s):

Souad A.M. Al-Bat’hi ◽

Yose Fachmi Buys

Keyword(s):

Thin Film ◽

Solid Polymer ◽

Polymer Thin Film ◽

Photovoltaic Application

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A polymer thin-film technique to study the micromorphology of core/shell latexes

Journal of Polymer Science Part A Polymer Chemistry ◽

10.1002/pola.1987.080250924 ◽

1987 ◽

Vol 25 (9) ◽

pp. 2595-2603

Author(s):

O. L. Shaffer ◽

V. L. Dimonie ◽

M. S. El-Aasser ◽

J. W. Vanderhoff

Keyword(s):

Thin Film ◽

Core Shell ◽

Polymer Thin Film ◽

Thin Film Technique

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Phase Separation Gives Rise To Nanoparticle Ring Formation

Zeitschrift für Naturforschung A ◽

10.1515/zna-2003-7-802 ◽

2003 ◽

Vol 58 (7-8) ◽

pp. 392-396

Author(s):

L.V. Govor ◽

J. Parisi ◽

G. H. Bauer

Keyword(s):

Thin Film ◽

Phase Separation ◽

Polymer Solution ◽

Particle Diameter ◽

Bottom Layer ◽

Polymer Thin Film ◽

Self Assembling ◽

Binary Polymer ◽

Ring Diameter ◽

Ultrathin Polymer Films

We report on the formation of self-assembled rings of CoPt3 nanoparticles in ultrathin polymer films (ring diameter about 1 μm, particle diameter 6 nm). The polymer thin film was formed by wetting a polymer solution on the surface of water. The process of self-assembling turns out to result from phase separation of the binary polymer solution film used, the subsequent dewetting of the top layer, and its decomposition into droplets on the surface of the bottom layer.

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Effect of Illumination on Organic Polymer Thin-Film Transistors

MRS Proceedings ◽

10.1557/proc-771-l10.17 ◽

2003 ◽

Vol 771 ◽

Cited By ~ 3

Author(s):

Michael C. Hamilton ◽

Sandrine Martin ◽

Jerzy Kanicki

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Drain Current ◽

Charge Carriers ◽

Electrical Performance ◽

Organic Polymer ◽

Light Illumination ◽

Polymer Thin Film ◽

Channel Region ◽

White Light Illumination

AbstractWe have investigated the effects of white-light illumination on the electrical performance of organic polymer thin-film transistors (OP-TFTs). The OFF-state drain current is significantly increased, while the drain current in the strong accumulation regime is relatively unaffected. At the same time, the threshold voltage is decreased and the subthreshold slope is increased, while the field-effect mobility of the charge carriers is not affected. The observed effects are explained in terms of the photogeneration of free charge carriers in the channel region due to the absorbed photons.

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A Time-Resolved Low-Angle Light Scattering Apparatus. Application to Phase Separation Problems in Polymer Systems

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20010973 ◽

2001 ◽

Vol 66 (6) ◽

pp. 973-982 ◽

Cited By ~ 5

Author(s):

Čestmír Koňák ◽

Jaroslav Holoubek ◽

Petr Štěpánek

Keyword(s):

Phase Separation ◽

Light Scattering ◽

Signal To Noise Ratio ◽

Scattered Light ◽

Ccd Camera ◽

Time Resolved ◽

Polymer Systems ◽

Software Analysis ◽

Phase Separation Kinetics ◽

Small Angle Light Scattering

A time-resolved small-angle light scattering apparatus equipped with azimuthal integration by means of a conical lens or software analysis of scattering patterns detected with a CCD camera was developed. Averaging allows a significant reduction of the signal-to-noise ratio of scattered light and makes this technique suitable for investigation of phase separation kinetics. Examples of applications to time evolution of phase separation in concentrated statistical copolymer solutions and dissolution of phase-separated domains in polymer blends are given.

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Conducting polymer thin film for optoelectronic devices applications

Polymers for Advanced Technologies ◽

10.1002/pat.5290 ◽

2021 ◽

Author(s):

Mohamed H. Abdel‐Aziz ◽

Mohammed Zwawi ◽

Ahmed F. Al‐Hossainy ◽

Mohamed Sh. Zoromba

Keyword(s):

Thin Film ◽

Conducting Polymer ◽

Optoelectronic Devices ◽

Polymer Thin Film

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A Novel Thin-Film Technique to Improve Accuracy of Fluorescence-Based Estimates for Periphytic Biofilms

Water ◽

10.3390/w13111464 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1464

Author(s):

Leon Katona ◽

Yvonne Vadeboncoeur ◽

Christopher T. Nietch ◽

Katie Hossler

Keyword(s):

Thin Film ◽

Thin Films ◽

Light Attenuation ◽

Pulse Amplitude ◽

Light Signal ◽

Photosynthetic Parameters ◽

Pam Fluorometry ◽

Attenuation Coefficients ◽

Thin Film Technique ◽

Relative Errors

Recent studies suggest that photophysiological parameters for intact substrates with depth (e.g., periphytic biofilms, microphytobenthos) are overestimated by pulse-amplitude modulated (PAM) fluorometry. This overestimation results from depth-integration effects, following the activation of deeper photosynthesizing layers by an attenuated light signal. To mitigate this error, we propose a novel slide-based thin-film technique in which fluorescence is measured on a vertically representative subsample of the biofilm, spread evenly on a microscope slide. We compared bias and precision for photosynthetic parameters estimated through conventional PAM fluorometry on intact biofilms and through our novel slide-based technique, both theoretically and empirically. Numerical simulations confirmed the consistent overestimation of key parameters for intact biofilms, with relative errors up to 145%, compared to, at most, 52% on thin films. Paired empirical observations likewise demonstrated that estimates based on intact biofilms were consistently higher (up to 248%, p<0.001) than estimates from thin films. Numerical simulation suggested greater precision with the slide-based technique for homogeneous biofilms, but potentially less precision for heterogeneous biofilms with improper subsampling. Our empirical comparison, however, demonstrated some improvement in precision with the slide-based technique (e.g., the coefficient of variation for the maximum electron transport rate was reduced 30%, p=0.009). We recommend the use of the slide-based technique, particularly for biofilms that are thick or have small light attenuation coefficients. Care should be taken, however, to obtain vertically representative subsamples of the biofilm for measurement.

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A Theoretical Study on an Elastic Polymer Thin Film-Based Capacitive Wind-Pressure Sensor

Polymers ◽

10.3390/polym12092133 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2133

Author(s):

Xue Li ◽

Jun-Yi Sun ◽

Bin-Bin Shi ◽

Zhi-Hang Zhao ◽

Xiao-Ting He

Keyword(s):

Thin Film ◽

Closed Form ◽

Pressure Sensor ◽

Closed Form Solution ◽

Form Solution ◽

Wind Pressure ◽

Polymer Thin Film ◽

Movable Electrode ◽

Elastic Polymer ◽

Electrode Plate

This study is devoted to the design of an elastic polymer thin film-based capacitive wind-pressure sensor to meet the anticipated use for real-time monitoring of structural wind pressure in civil engineering. This sensor is composed of four basic units: lateral elastic deflection unit of a wind-driven circular polymer thin film, parallel plate capacitor with a movable circular electrode plate, spring-driven return unit of the movable electrode plate, and dielectric materials between electrode plates. The capacitance of the capacitor varies with the parallel move of the movable electrode plate which is first driven by the lateral elastic deflection of the wind-driven film and then is, after the wind pressure is reduced or eliminated, returned quickly by the drive springs. The closed-form solution for the contact problem between the wind-driven thin film and the spring-driven movable electrode plate is presented, and its reliability is proved by the experiment conducted. The numerical examples conducted show that it is workable that by using the numerical calibration based on the presented closed-form solution the proposed sensor is designed into a nonlinear sensor with larger pressure-monitoring range and faster response speed than the linear sensor usually based on experimental calibration.

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