Effect of Phosphoric Acid Anion Structure on the Corrosion Inhibition of Steel by Polyaniline

Conductive polymers such as polyaniline (PAni) have been examined as candidates for replacing the existing chromate systems. Protonation of emeraldine base creates polarons and bipolarons, single and paired radical cations, respectively, of higher bond energy levels within the molecular orbital band gap.\u27 For a conductive coating, considerable delocalization of corrosion charge and potential may be obtained along or between the polymer chains, because of high electron mobility. Current corrosion systems based on polyaniline typically rely on sulfuric or sulfonic acids as a dopant material, since synthetic techniques utilize persulfates as the oxidant of choice. In our experience, sulfonic/sulfuric acid systems do not produce adequate corrosion protection. However, few studies have been made of alternative dopant anions. Presumably additional studies are deemed of limited benefit because the persulfate synthesis is prevalent and time intensive purifications are required for replacing an existing sulfonic/sulfuric dopant anion. A. dopant study could yet be important to achieving a more effiCient inhibition system. Phosphonates are derivatives of phosphonic acids that contain direct phosphorous-to-carbon bonds (P-C). The P-C bonds are more resistant to hydrolysis than the P-O-C bonds of orgamc phosphates.3 Phosphonic acids are used as scale inhibitors in. Aqueous systems, the use of these acids as dopants in polyamhne could improve corrosion protection exhibited by polyaniline. Kinle.n el aL4 have reported that phosphonic acid doped polyamhne in polyvinylbutyrallatex coatings showed decreasing galvanic activity with time, providing pinhole passivation. We report testing of an Identical series of doped polyanilines as that of Kinlen, et aL applied in an epoxy polyamide coating system

Optically Transparent Composite Material and Process for Preparing Same

Glass ribbon-reinforced transparent polymer composites which provide excellent optical transparency and a low distortion level over a wide temperature range while exhibiting superior mechanical properties as compared to non- reinforced polymer counterparts, and equivalent properties as compared to glass fiber-reinforced counterparts

2,4-Dinitrophenylhydrazones of 2,4-dihydroxybenzaldehyde, 2,4-dihydroxyacetophenone and 2,4-dihydroxybenzophenone

In 2,4-dihydroxybenzaldehyde 2,4-dinitrophenylhydrazone N,N-dimethylformamide solvate (or 4-[(2,4-dinitrophenyl)-hydrazonomethyl]benzene-1,3-diol N,N-dimethylformamide solvat

Additive-Assisted, Cerium-Based, Corrosion-Resistant e-coating

Corrosion resistance of metallic components such as stainless steel components of vehicles, and especially aluminum- based components of aircraft, is enhanced by application of an e-coat paint or primer which is enhanced by incorporation of cerium ions into the e-coat electrolytic bath. The resulting overall coating includes a cerium-based layer under a cerium-enhanced e-coat paint or primer layer

Additive-Assisted Cerium-Based Electrolytic Coating Process for Corrosion Protection of Aluminum Alloys

The corrosion resistance of an aluminum or aluminum alloy component is enhanced by immersing an aluminum alloy to act as a cathode and an oxygen-evolving anode in an electrolyte comprising water, cerium ions, and an additive selected from among animal gelatin, derivatives of animal gelatin, and amino acids, then passing an electrical current through the electrolyte to deposit a cerium-based coating onto the aluminum-based component

Cerium-Based Spontaneous Coating Process for Corrosion Protection of Aluminum Alloys

A cerium-based coating for corrosion resistance is applied by exposing a cleaned aluminum-based component to a corrosion-inhibiting cerium solution containing cerium ions in the presence of an oxidizing agent. The coating deposits spontaneously without an external source of electrons

THE REACTION OF HEXACHLORO CYCLOPENTADIENE WITH AMINES

Abstract not availabl

Chemistry of the Silane Coupling Agents in Coatings

Adhesion of a coating can be improved by the use of silane coupling agents. The preparation, application and properties of silane coupling agents is presented. The mechanism for the formation of Si-O-Substrate bonds will be discussed. Kinetic data, adhesion data and electron photomicrographs is discussed to support work on the rate of exchange of one alkoxy group for another on these silanes to give information about the bond-breaking/bond-formation process which is similar to that which occurs with silane coupling agents. The author prepared a series of epoxy coatings on mild steel which were subjected to salt-fog chamber exposure. These lasted in excess of 500 hours in the salt-fog chamber, whereas those without the silane coupling agent failed in less time

Investigation of a Direct Synthesis of Silicone Precursors

In this paper, we are reporting our recent efforts on the direct synthesis procedure of methyl phenoxy silane monomers by the reaction of elemental silicon with anisole, Ph-O-Me. This procedure gave about 4%, 8% and 40% of dimethyl diphenoxy, methyl triphenoxy and tetraphenoxy silane respectively under the experimental conditions. The anisole reacts with elemental silicon directly in the present of catalyst copper (I) chloride at a high temperature and pressure. The major products were teraphenoxy silane (40%), and small amount of methyl triphenoxy silane (8%) and dimethyl diphenoxy silane (4%)