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Thickness Gauging
Published in David M. Scott, Industrial Process Sensors, 2018
In order to demonstrate the use of this optical technique in measuring film thickness, a series of measurements were made on single Kapton® films ranging from 30 to 500 gauge (7.6–127 μm thick). Sample films were fixed to a small washer that was attached to the glass slide on the testing device. The purpose of the washer was to provide a standoff so that the front surface of the slide would not interfere with the back surface of the film. A sketch of the experimental response curve obtained with a sample of 100-gauge polyimide film is shown in Figure 10.20. There are two prominent peaks: one corresponds to the front surface of the film, and the other corresponds to the back surface. The separation of the peaks is the optical film thickness t; this value is converted into the film thickness t using the correction factor given in equation 10.33.
Carbon Membranes for Gas Separation
Published in Stephen Gray, Toshinori Tsuru, Yoram Cohen, Woei-Jye Lau, Advanced Materials for Membrane Fabrication and Modification, 2018
Kapton is a polyimide obtained by curing the polyamic acid prepared by condensation of pyromellitic dianhydride (PMDA) with oxydianiline (ODA). Because both Kapton and its precursor polyamic acid are available commercially, they are frequently used as starting materials for CMS membranes. Suda and Haraya (1995; 1997a; 1997b) prepared flat carbon membranes by carbonizing Kapton films. When the pyrolysis process was suitably controlled, the Kapton CMS membrane showed high performance, with H2/N2 and O2/N2 selectivities of 4700 and 36, respectively, at 35°C. Fuertes et al. (1999) prepared asymmetric flat CMS membranes from PMDA-ODA polyamic acid membranes by spin-coating the polymer on a porous carbon disk with subsequent phase inversion.
Ion Beam Modification of Polyimides
Published in Malay K. Ghosh, K. L. Mittal, Polyimides Fundamentals and Applications, 2018
Polyimides are used extensively in situations requiring high-performance plastic materials, where other engineering materials do not function, because of their unique combination of superior mechanical, electrical, chemical and thermal properties. Kapton, a popular polyimide, is able to operate in temperature extremes as low as –269°C and as high as 400°C [1]. In particular, its excellent insulating properties, together with radiation resistance, and fire resistance, have made this polyimide one of the favorite choices for applications in wire and cable insulation, electrical component seal assemblies, and component leads in nuclear power plants, military aircraft, and space shuttles [2,3]. Other applications include various electronic components such as flexible circuits, semiconductor pads, microprocessor chip carriers, coil insulation, magnetic wire insulation, and solar arrays.
Poly(tetramethylene oxide)-coated silica nanoparticles incorporated into poly(4,4′-oxydiphenylene-pyromellitimide) matrix
Published in Materials and Manufacturing Processes, 2018
Maryam Karimzadeh, Elahesadat Eslampanah-Seyyedi, Hossein Behniafar
Poly(4,4′-oxydiphenylene-pyromellitimide) (POPI) is the chemical name for Kapton®HN polyimides. Kapton®HN polyimides form a class of high-performance polymers with certain outstanding characteristics, such as high thermal stability, chemical inertness, low dielectric constants, and strong adhesion to most semiconductors.[123] These polymers are produced from the condensation polymerization of 4,4′-oxydiphenylamine (4,4′-ODA) and pyromellitic dianhydride (PMDA). Moreover, it has been demonstrated that silica nanoparticles (SNPs) can effectively improve the thermal and mechanical properties of polymer materials.[4567] Due to incompatibility challenge of the inorganic silica with the organic polymer, SNPs should be organically modified prior to loading process. This organomodification also can prevent the nanosized particles from agglomeration event as an unfavorable phenomenon.