Kapton polyimide

As stated, the capability of plasma deposits to reduce the access of water to corrosion-sensitive surfaces may be an important motivation for their application in corrosion protection. In order to study this property, Kapton polyimide film was selected as the substrate because of its high inherent permeability to water and its ability to resist elevated temperatures. The response of Kapton film overcoated by PPHMDSO to the permeation of water vapor is shown in Fig. 1. Clearly, the presence of the organo-silicone plasma film greatly reduces water permeation. The magnitude of the effect is much enhanced when plasma polymers are produced at high T and p. 

DuPont Kapton Polyimide Film, DuPont DeNemours Literature. 

D. J. Parish and B. W. Melvin, Kapton polyimide film in rotating machinery, a paper presented at the 6th Electrical Insulation Conference (IEEE and NEMA), Sep. 1965. 

Toray-DuPont Product Bulletin for Kapton polyimide film. 

We will continue platform extensions, taking Nafion fluoropolymer membranes from chloralkali cells and catalysts to advanced fuel cells, and Kapton polyimide film from flat electronic computer circuits to complex flexible circuits in cell... 

Screen printing is an excellent method for fabrication of ISEs on an industrial scale. Ag/AgCI electrodes can be screen printed onto a suitable support such as Kapton polyimide. The selective membrane is then printed onto the ISE, often with an intervening layer of a hydrogel such as poly(vinyl alcohol) soaked with NaCl solution to act as the internal reference solution. The reductions of cost associated with the mass-production of these electrodes allow them to be sold as single-use disposable devices. Also their small size relative to conventional ISEs allows them to be assembled into sensor arrays. 

To confront these difficult tasks, we have incorporated old and new solutions. For example, strong yet flexible Kapton polyimide substrates are promising, and the neutral-carrier type ion-selective membranes offer the advantage of using similar fabrication methods for sensors of different ions of interest. We are also working on the biocompatibility problems, and all new designs are subject to in vivo tests. 

Since the commercialization of Kapton polyimide film by DuPont, more than 30 years ago, a great number of polyimides have been described covering a very... 

Kapton polyimide has been widely used in the electronic industry because of its low dielectric constant, good mechanical properties and high thermal stability. Many applications require good adhesion between Kapton polyimide film and metal. Various processes to improve adhesion of metal to Kapton polyimide have been reported in the literature. DeAngelo et al., (D describe a process to form metal oxides on the surface of polyimide to improve adhesion. Other efforts to improve adhesion of a metal layer involve roughening of the surface of polyimide substrate by methods such as cathodic sputtering (2), chemical attack (2., 1), and reactive ion etching (1,4). 

We have recently modified the Krause process by incorporating a heat treatment step which results in a novel process for surface texturing of Kapton polyimide (Somasiri, N. L. D. Speckhard, T. A. U. S. Patent Applied For). When the textured polyimide is subsequently metallized, again using the Krause process, good adhesion is obtained after exposure to the solder float test. 

Surface topography of Kapton polyimide as-received, seeded with copper, after the 450°C heat treatment, and after removal of copper oxide by acid etching was examined by scanning electron microscopy. Cross-sectional analysis of Kapton seeded with copper and after 450°C heat treatment was carried out by transmission electron microscopy. 

Figure 1. Scanning electron micrographs of Kapton polyimide (a) as-received, (b) seeded with copper, (c) after 450°C heat treatment, and (d) after heat treatment and removal of all copper oxide.

Figure 2. Transmission electron micrographs of Kapton polyimide (magnification 36000X) (a) seeded with copper and (b) after...

When subject to 90° peel test, adhesion values of 7-10 lbs/in have been obtained under ambient conditions. Interestingly, the adhesion after the solder float test retained 4-6 lbs/in. This high adhesion is believed to be primarily due to the mechanical interlocking facilitated by the textured Kapton polyimide. 

Polyimides have excellent dielectric strength and a low dielectric constant, but in certain electrolyte solutions they can electrochemically transport electronic and ionic charge. Haushalter and Krause (5) first reported that Kapton polyimide films derived from 1,2,4,5-pyromellitic dianhydride (PMDA) and 4,4 -oxydianiline (ODA) undergo reversible reduction/oxidation (redox) reactions in electrolyte solutions. Mazur et al., (6) presented a detailed study of the electrochemical properties of chemically imidized aromatic PMDA- derived polyimides and model compounds in nonaqueous solutions. Thin films of thermally... 

Figure 11.8 S parameter versus positron incident energy in different polymers. PVC-polyvinyl chloride, PU-polyurethane. TEFLON—polytetrafluoroethylene, KAPTON—polyimide [28],...

Kapton Polyimide Film" Summary of Properties, DuPont Technical Bulletin, E-50533 (1982). 

Polyimides for microelectronics use are of two basic types. The most commonly used commercial materials (for example, from Dupont and Hitachi) are condensation polyimides, formed from imidization of a spin-cast film of soluble polyamic acid precursor to create an intractable solid film. Fully imidized thermoplastic polyimides are also available for use as adhesives (for example, the LARC-TPI material), and when thermally or photo-crosslink able, also as passivants and interlevel insulators, and as matrix resins for fiber-reinforced-composites, such as in circuit boards. Flexible circuits are made from Kapton polyimide film laminated with copper. The diversity of materials is very large readers seeking additional information are referred to the cited review articles [1-3,6] and to the proceedings of the two International Conferences on Polyimides [4,5]. 

Figure 7.42. Experimental setup and eastic recoil detection (ERD) spectra for multiwalled nanotubes, and a Kapton polyimide film. A computer program, SIMRA, is useful to simulate ERD as well as other non-RBS data. Reproduced with permission from Naab, F. U. Holland, O. W. Duggan, J. L. McDaniel, F. D. J. Phys. Chem. B 2005,109, 1415. Copyright 2005 American Chemical Society.

Fig. 3. Scanning electron micrograph of a Kapton polyimide surface that was exposed to the low Earth orbital ram environment for 40 hours on the STS-46 space shuttle mission. The smooth portion of the Kapton surface was covered during exposure and therefore shows no erosion. The rougher portion of the surface shows the topography and extent of erosion (6 /rm deep) resulting from the exposure.

Since the first commercialization of Kapton polyimide nearly three decades ago, an impressive number of new polyimides of unique properties have been introduced for various industrial and consumer product applications. Commercial and semi-commercial production of numerous new monomers have made it possible to explore seemingly infinite varieties of structurally different polyimides and copolyimides. As a result we seem to have a more finely tuned understanding of structure-property relationship necessary for a specific application. Research and development activities in new polyimides seem to be intensifying rather than reaching its maturity. In this article, recent advances in polyimides are reviewed in the area of scientific activity as well as commercial developments. 

Kapton" Polyimide Film. Physical-Thermal Properties, Bulletin H-2 "Kapton" Polyimide Film — Type H. Summary of Properties, Bulletin H-ID. E. I. Du Pont de Nemours Co.,... 

Kapton polyimide is used extensively on spacecraft in flexible substrates for lightweight, high-power solar arrays because of its inherent strength, temperature stability, excellent insulation properties, UV stability and IR transparency. It is also used in conjunction with Teflon FEP in multilayer insulation blankets for thermal control insulation because of its superior optical properties, including low solar absorptance. In these multilayer insulation blankets, aluminium (or gold) is typically applied to Kapton due to its low emissivity [1]. 

It was found that the incorporation of POSS slightly reduces the glass transition temperature (Tg) of Kapton polyimide, however, the Tg values of POSS-PIs are well above the temperatures experienced by materials in LEO. The CTE of POSS-PIs is similar to the CTE of commercial Kapton H . A new SC-POSS monomer imparts about the same AO resistance to polyimides as the MC-POSS monomer. The modulus, Tg, and CTE of SC-POSS-PIs were determined before and after exposure to atomic oxygen, and are comparable to the values of these properties for Kapton H . 

During the past three decades, since the commercialization of Kapton polyimide, an impressive variety of polyimides have been synthesized [258, 259]. Polyimides possess outstanding key properties, such as thermooxidative stability [260], high mechanical strength [261], high modules, excellent electrical [262] and optical properties [263, 264], and superior chemical resistance [265]. Recently polyimides have also been applied as membranes for gas separation [266, 267]. Approximately 15 years ago the direct structuring or laser ablation of polyimides by excimer lasers was first described [73, 130]. 

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