Phase Transitions and Surface Characterization of Poly (Butylene Terephthalate) Fibers by Photoacoustic and Diffuse Reflectance Fourier Transform Infrared Spectroscopy

Diffuse reflectance and photoacoustic (PAS) IR techniques are used for spectral measurements of poly(butylene terephthalate) (PBT) fibers. The spectral observations on the fibers are similar to those observed in films. The stress-induced phase transformation is reversible with annealing of the drawn fibers. The annealing process also increases the amount of crystallinity in the fiber. With the use of recently developed PAS methodology to study orientation of the surface species, the orientation of surface aromatic and carbonyl groups is analyzed. In the alpha phase, the surface aromatic rings are preferentially perpendicular on the surface whereas carbonyl groups are preferentially parallel. A similar orientation is observed in the drawn fibers. Annealing of the drawn fibers changes the orientation of the aromatic rings. Upon annealing, the phenyl rings are preferentially parallel to the surface. The depth of penetration at 3000 cm−1 in PBT fibers is found to be approximately 4 μ.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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Surface characterization of Au/HY by 129XeNMR and diffuse reflectance IR spectroscopy of adsorbed CO. Formation of electron-deficient gold particles inside HY cavities

Journal of the Chemical Society Faraday Transactions ◽

10.1039/a703431h ◽

1997 ◽

Vol 93 (19) ◽

pp. 3587-3591 ◽

Cited By ~ 68

Author(s):

D. Guillemot ◽

V. Yu. Borovkov ◽

V. B. Kazansky ◽

M. Polisset-Thfoin ◽

J. Fraissard

Keyword(s):

Ir Spectroscopy ◽

Surface Characterization ◽

Diffuse Reflectance ◽

Gold Particles ◽

Adsorbed Co

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Characterization of Surface Contaminants by a Silver Film-Enhanced IR—Johnson Method

Applied Spectroscopy ◽

10.1366/0003702971939226 ◽

1997 ◽

Vol 51 (10) ◽

pp. 1460-1463 ◽

Cited By ~ 11

Author(s):

Nobuaki Marino ◽

Kiichirou Murai ◽

Yoshinori Kataora

Keyword(s):

Polymer Film ◽

Silicon Wafer ◽

Photoelectron Spectroscopy ◽

Present Method ◽

Surface Characterization ◽

Diffuse Reflectance ◽

Silver Film ◽

Wafer Surface ◽

Surface Contaminants

Characterization of nanometer-order organic contaminants on polymer film and silicon wafer surface has been investigated by a modified IR–Johnson method. We have proposed a silver film-enhanced IR–Johnson method that is useful for surface contaminant analysis. In the present method, organic traces are transferred from the surface of a polymer film or silicon wafer onto the KBr particles deposited with silver film, and then the KBr particles are analyzed directly by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Infrared absorption of organic traces was enhanced by the presence of silver island film. With this method, a spectrum of nanometer-order organic traces can be obtained without any interference from the polymer film substrate. The present method is as surface-sensitive as X-ray photoelectron spectroscopy (XPS) and provides a large amount of information on the chemical structure of surface contaminants. This is a promising method for the surface characterization of polymer films and silicon wafer. Index Headings: Infrared; Diffuse reflectance; Surface enhancement.

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Drifts surface characterization of Zincblende nanostructured GaN

MRS Proceedings ◽

10.1557/proc-501-191 ◽

1997 ◽

Vol 501 ◽

Cited By ~ 1

Author(s):

Kenneth E. Gonsalves ◽

Greg Carlson ◽

Marie-Isabelle Baraton

Keyword(s):

Polymer Nanocomposites ◽

Surface Characterization ◽

Diffuse Reflectance ◽

Chemical Species ◽

Atomic Layer ◽

Surface Chemical ◽

Nanosized Powder ◽

Fourier Transform Spectrometry ◽

Diffuse Reflectance Infrared

ABSTRACTThe use of GaN/polymer nanocomposites in optoelectronics requires a perfect control of the GaN dispersion in the polymer matrix. This cannot be achieved without a good knowledge of the first atomic layer of the GaN nanoparticles. This paper reports the characterization of the surface chemical species of a GaN nanosized powder by diffuse reflectance infrared Fourier transform spectrometry.

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Chemical and orientational imaging of polymeric samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168074 ◽

1994 ◽

Vol 52 ◽

pp. 68-69

Author(s):

H. Ade ◽

B. Hsiao ◽

G. Mitchell ◽

E. Rightor ◽

A. P. Smith ◽

...

Keyword(s):

Ethylene Terephthalate ◽

National Laboratory ◽

Brookhaven National Laboratory ◽

Carbonyl Groups ◽

Aromatic Rings ◽

Edge Structure ◽

X Ray ◽

Scanning Transmission ◽

Polymeric Samples ◽

X Ray Absorption

We have used the Scanning Transmission X-ray Microscope at beamline X1A (X1-STXM) at Brookhaven National Laboratory (BNL) to acquire high resolution, chemical and orientation sensitive images of polymeric samples as well as point spectra from 0.1 μm areas. This sensitivity is achieved by exploiting the X-ray Absorption Near Edge Structure (XANES) of the carbon K edge. One of the most illustrative example of the chemical sensitivity achievable is provided by images of a polycarbonate/pol(ethylene terephthalate) (70/30 PC/PET) blend. Contrast reversal at high overall contrast is observed between images acquired at 285.36 and 285.69 eV (Fig. 1). Contrast in these images is achieved by exploring subtle differences between resonances associated with the π bonds (sp hybridization) of the aromatic groups of each polymer. PET has a split peak associated with these aromatic groups, due to the proximity of its carbonyl groups to its aromatic rings, whereas PC has only a single peak.

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