Metal – polymer interfaces and their effect on the glass transition of thin polystyrene films

2003 ◽  
Vol 790 ◽  
Author(s):  
J.S. Sharp ◽  
J.A. Forrest
Keyword(s):  
Glass Transition ◽  
Metal Layer ◽  
Interfacial Structure ◽  
Polymer Interfaces ◽  
Force Microscopy ◽  
Atomic Force ◽  
Polymer Metal ◽  
Sample Preparation Procedure ◽  
Metal Interfaces ◽  
Metal Polymer

ABSTRACTWe present a study of polystyrene-metal interfaces and discuss the relationship between the interfacial structure and anomalies in the measured glass transition temperature (Tg) of thin metal capped polystyrene (PS) films. The PS films used in these studies were coated with an evaporated metal layer of either Aluminum (Al) or gold (Au) and the Tg values were measured with ellipsometry. Uncoated PS films were also measured and these samples showed Tg values that were reduced relative to the bulk value for film thicknesses (h) less than 40 nm. Films coated with Au were shown to have measured Tg values that were the same as the bulk value (Tgbulk=370 K) for all the film thicknesses studied (h ≥ 8nm). The Al coated PS films had measured Tg values that were the same as the uncoated PS films. The observed differences are discussed in terms of the differences in the structure of the metal-polymer interfaces produced during thermal evaporation of the metal layers. A novel sample preparation procedure was developed to enable us to use Atomic Force Microscopy (AFM) to directly measure the structure of the buried polymer-metal interfaces. The measurements performed on these systems support the suggestion that the interfacial structure is different for the two metal-polymer interfaces studied and that these differences may be the cause of the anomalies in the measured Tgs of these samples.

Novel Method for High-Spatial-Resolution Chemical Analysis of Buried Polymer-Metal Interface: Atomic Force Microscopy-Infrared (AFM-IR) Spectroscopy with Low-Angle Microtomy

2021 ◽  
pp. 000370282110071
Author(s):  
Naoki Baden
Keyword(s):  
Atomic Force Microscopy ◽  
Ir Spectroscopy ◽  
Chemical Analysis ◽  
Cross Section ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Force Microscopy ◽  
Atomic Force ◽  
Polymer Metal ◽  
Metal Interfaces

There is a great need for the analysis of the chemical composition, structure, functional groups, and interactions at polymer-metal interfaces in terms of adhesion, corrosion, and insulation. Although atomic force microscopy-based infrared (AFM-IR) spectroscopy can provide chemical analysis with nanoscale spatial resolution, it generally requires to thin a sample to be placed on a substrate that has low absorption of infrared light and high thermal conductivity, which is often difficult for samples that contain hard materials such as metals. This study demonstrates that the combination of AFM-IR with low-angle microtomy (LAM) sample preparation can analyze buried polymer-metal interfaces with higher spatial resolution than that with the conventional sample preparation of a thick vertical cross-section. In the LAM of a polymer layer on a metal substrate, the polymer layer is tapered to be thin in the vicinity of the interface, and thus, sample thinning is not required. An interface between an epoxyacrylate layer and copper wire in a flexible printed circuit cable was measured using this method. A carboxylate interphase layer with a thickness of ∼130 nm was clearly visualized at the interface, and its spectrum was obtained without any signal contamination from the neighboring epoxyacrylate, which was difficult to achieve on a thick vertical cross-section. The combination of AFM-IR with LAM is a simple and useful method for high-spatial-resolution chemical analysis of buried polymer-metal interfaces.

The Reactive Formation of Diblock Copolymer at a Polymer/Polymer Interface and its Effect on Interfacial Structure

2000 ◽  
Vol 629 ◽  
Author(s):  
Jonathan S. Schulze ◽  
Timothy P. Lodge ◽  
Christopher W. Macosko
Keyword(s):  
Molecular Weight ◽  
Interfacial Structure ◽  
Root Mean Square Roughness ◽  
Radius Of Gyration ◽  
Interfacial Region ◽  
Force Microscopy ◽  
Amino Terminal ◽  
Polymer Interface ◽  
Atomic Force ◽  
Time Required

ABSTRACTThe reaction of perdeuterated amino-terminal polystyrene (dPS-NH2) with anhydrideterminal poly(methyl methacrylate) (PMMA-anh) at a PS/PMMA interface has been observed with forward recoil spectrometry (FRES). Bilayer samples were constructed by placing thin films of PS containing ∼8.5 wt % dPS-NH2 on a PMMA-anh layer. Significant reaction was observed only after annealing the samples at 174°C for several hours, a time scale at least two orders of magnitude greater than the time required for the dPS-NH2 chains to diffuse through the bulk PS layer. The topography of the interfacial region as copolymer formed was measured using atomic force microscopy (AFM). Roughening of the PS/PMMA interface was observed to varying degrees in all annealed samples. Furthermore, the extent of this roughening was found to depend on the PS matrix molecular weight. Reaction in the samples with a high molecular weight PS matrix resulted in a root mean square roughness approximately equal to the radius of gyration Rg of the copolymer. However, approximately twice as much roughening was observed in the low molecular weight PS matrix. This study reveals how the molecular weight of one of the phases can affect the rate of reaction at a polymer/polymer interface.

scholarly journals Ultrafine metal-polymer catalysts based on polyconjugated systems for Fisher–Tropsch synthesis

2020 ◽  
Vol 92 (6) ◽  
pp. 977-984
Author(s):  
Mayya V. Kulikova ◽  
Albert B. Kulikov ◽  
Alexey E. Kuz’min ◽  
Anton L. Maximov
Keyword(s):  
Tropsch Synthesis ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
Force Microscopy ◽  
Composite Catalysts ◽  
Fe Catalyst ◽  
Atomic Force ◽  
And Function ◽  
Metal Polymer

AbstractFor previously studied Fischer–Tropsch nanosized Fe catalyst slurries, polymer compounds with or without polyconjugating structures are used as precursors to form the catalyst nanomatrix in situ, and several catalytic experiments and X-ray diffraction and atomic force microscopy measurements are performed. The important and different roles of the paraffin molecules in the slurry medium in the formation and function of composite catalysts with the two types of aforementioned polymer matrices are revealed. In the case of the polyconjugated polymers, the alkanes in the medium are “weakly” coordinated with the metal-polymer composites, which does not affect the effectiveness of the polyconjugated polymers. Otherwise, alkane molecules form a “tight” surface layer around the composite particles, which create transport complications for the reagents and products of Fischer-Tropsch synthesis and, in some cases, can change the course of the in situ catalyst formation.

Scratching the surface: Imaging interfacial structure using atomic force microscopy

Food Colloids ◽  
2007 ◽  
pp. 13-21 ◽  
Author(s):  
Alan R. Mackie ◽  
A. Patrick Gunning ◽  
Peter J. Wilde ◽  
Victor J. Morris
Keyword(s):  
Atomic Force Microscopy ◽  
Interfacial Structure ◽  
Surface Imaging ◽  
Force Microscopy ◽  
Atomic Force

Novel Flexible NH3 Gas Sensor Prepared by Ink-Jet Printing Technique

2012 ◽  
Vol 506 ◽  
pp. 39-42 ◽  
Author(s):  
C. Wongchoosuk ◽  
P. Jangtawee ◽  
P. Lokavee ◽  
S. Udomrat ◽  
P. Sudkeaw ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Low Cost ◽  
Metal Electrode ◽  
Ink Jet Printing ◽  
Force Microscopy ◽  
Sensing Mechanism ◽  
Atomic Force ◽  
Ink Jet ◽  
Polymer Metal ◽  
Jet Printing

We have fabricated a low-cost and flexible NH3 gas sensor using thermal ink-jet printing. The poly (3,4-ethylene dioxythiophene) doped with polystyrene sulfonated acid (PEDOT/PSS) with thickness of ~ 2 μm was used as a sensing film. The interdigitated electrode using patterned aluminum plate was attached over the sensing film. Atomic force microscopy results show the high homogeneous film and only small roughness is presented on the sensing film. This sensor exhibits high selectivity and sensitivity to NH3 at room temperature. The sensor response works linearly with gas concentrations between 100-1000 ppm. The modulation of conducting polymer/metal electrode interface plays a role in the sensing mechanism of NH3. Changes in the position of interdigitated electrodes can change the dominant sensing mechanism of typical polymer gas sensor.

scholarly journals Subsurface imaging of flexible circuits via contact resonance atomic force microscopy

2019 ◽  
Vol 10 ◽  
pp. 1636-1647 ◽  
Author(s):  
Wenting Wang ◽  
Chengfu Ma ◽  
Yuhang Chen ◽  
Lei Zheng ◽  
Huarong Liu ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Theoretical Calculations ◽  
Contact Stiffness ◽  
Metal Layer ◽  
Experimental Results ◽  
Subsurface Imaging ◽  
Force Microscopy ◽  
Atomic Force ◽  
Cover Thickness ◽  
Contact Resonance

Subsurface imaging of Au circuit structures embedded in poly(methyl methacrylate) (PMMA) thin films with a cover thickness ranging from 52 to 653 nm was carried out by using contact resonance atomic force microscopy (CR-AFM). The mechanical difference of the embedded metal layer leads to an obvious CR-AFM frequency shift and therefore its unambiguous differentiation from the polymer matrix. The contact stiffness contrast, determined from the tracked frequency images, was employed for quantitative evaluation. The influence of various parameter settings and sample properties was systematically investigated by combining experimental results with theoretical analysis from finite element simulations. The results show that imaging with a softer cantilever and a lower eigenmode will improve the subsurface contrast. The experimental results and theoretical calculations provide a guide to optimizing parameter settings for the nondestructive diagnosis of flexible circuits. Defect detection of the embedded circuit pattern was also carried out, which indicates the capability of imaging tiny subsurface structures smaller than 100 nm by using CR-AFM.

Dihedral Angle at Solid/Liquid-Polymer Interfaces Determined by Atomic Force Microscopy

Langmuir ◽  
1997 ◽  
Vol 13 (24) ◽  
pp. 6360-6362 ◽  
Author(s):  
Tobias Kerle ◽  
Sidney R. Cohen ◽  
Jacob Klein
Keyword(s):  
Atomic Force Microscopy ◽  
Dihedral Angle ◽  
Polymer Interfaces ◽  
Force Microscopy ◽  
Liquid Polymer ◽  
Atomic Force ◽  
Solid Liquid
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