Corrosion inhibitors, coatings

Isopropa.nola.mines. Reaction of propylene oxide with ammonia yields mono-, di-, and triisopropanolamines. These products find use as soluble oils and solvents, emulsifiers, waterless hand cleaners, cosmetics, cleaners, and detergents. In industrial apphcations isopropanolamines are used in adhesives, agricultural products, corrosion inhibitors, coatings, epoxy resins, metalworking, and others (51). 

Chem. Desaip. Cetyl palmitate CAS 540-10-3 EINECS/ELINCS 208-736-6 Uses Internal lubricant and binder in pressed binder operations emollient metalworking lubricant corrosion inhibitor coating for metal surfe. PrqtetUes Gardner 1+flakes pour pt. 51 C acid no. 0.2 iodine no. 1.0 max. nonionic 100% act. 

Uses Film-former in cosmetics release agent for plastics and rubber internal lubricant and release agent for sulfur and peroxide cure rubber coreactant in vinyl polymerization synthesis of org./silicone copolymers heat stabilizer for dimethyl silicone fluids in corrosion inhibitor coatings, UV and EB-cured inks and coatings cosmetic and personal care applies, incl. hair care Trade Names GP-71-SS Mercapto Modified Silicone Fluid... 

Properties Misc. with water m.w. 114.19 sp.gr. 0.94 b.p. 183 C (760 mm) flash pt. 167 F Toxicology LDLo (oral, rat) 1 g/kg LCLo (inh., rat, 4 h) 3200 mg/m si. toxic by ing. and inh. primary skin irritant TSCA listed Precaution Corrosive liq. combustible Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of NOx Uses Epoxy curing agent chelating agent for oil field, textile, water treatment, detergent fields herbicide intermediate polyamide resins for adhesives, films, plastics, inks PU for extenders catalysts scale/corrosion inhibitors coatings... 

Waterproofing copolymer emulsions Aqueous emulsion coatings for steel Steel corrosion inhibitor Coatings... 

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Dimethylethanolamine, diethylethanolaniine, and thek derivatives are used in pesticides, corrosion inhibitors, dmgs and pharmaceuticals, emulsification, paints and coatings, metal fabrication and finishing, petroleum and petroleum products, and plastics and resins (226). 

Other oxazolines synthesized from alkanolamines ate useful as surface-active agents and corrosion inhibitors. Synthetic oxazoline waxes promote lubricity and mat resistance of coatings. 

Cyclohexylamine is miscible with water, with which it forms an azeotrope (55.8% H2O) at 96.4°C, making it especially suitable for low pressure steam systems in which it acts as a protective film-former in addition to being a neutralizing amine. Nearly two-thirds of 1989 U.S. production of 5000 —6000 t/yr cyclohexylamine serviced this appHcation (69). Carbon dioxide corrosion is inhibited by deposition of nonwettable film on metal (70). In high pressure systems CHA is chemically more stable than morpholine [110-91-8] (71). A primary amine, CHA does not directiy generate nitrosamine upon nitrite exposure as does morpholine. CHA is used for corrosion inhibitor radiator alcohol solutions, also in paper- and metal-coating industries for moisture and oxidation protection. 

Corrosion and corrosion inhibitors Metal surface treati nts Metallic coatings). 

Thermoplastic polyamides are used in coatings to modify alkyd resins (qv) in thixotropic systems (238) and to plasticize nitroceUulose lacquers (239). DETA-taH oil fatty acid-based polyamides are suggested for use as corrosion inhibitors in alkyd paints (240). Printing inks for fiexo-gravure appHcation on certain paper, film and foil webs rely on EDA- and PDA-based polyamides for their specific performance (241). 

Ethylene oxide (qv), propylene oxide (qv), butylene oxide, and other epoxides react with ethanol to give a variety of Uquid, viscous, semiwax, and soUd products. These products are used ia the coatings iadustry as solvents, and as paints, antioxidants, corrosion inhibitors, and special-purpose polymers. Recent concerns about the health effects of ethanol containing glycol ethers have led to the decline in the production of these compounds. 

Separate the metal from the environment with a physical barrier. Many corrosion inhibitors make use of this principal to protect metals. Proper use of an appropriate inhibitor may reduce or eliminate pitting. Pits are frequently initiation sites for corrosion-fatigue cracks. The effectiveness of inhibitors depends upon their application to clean metal surfaces. An example of this method is the use of zinc coatings on steel to stifle pit formation. 

The need to identify replacements for chromate-based technologies has also resulted in the development of alternatives to resin-based corrosion-inhibiting primers. These are primarily inorganic barrier coating techniques, such as sol-gel processes, which may or may not include corrosion inhibitors. These are discussed in a later section. 

Application of Corrosion Inhibitors. There are basically two main techniques used to apply corrosion inhibitors in drilling operations. In the first method inhibitors are added to the drilling fluid system either by mixing the additives through the rig s chemical hopper or through additions into the mud pit. The treatment can be achieved in two ways, batch treatment or continuous treatment. In some cases it may be necessary to use both types of treatment simultaneously. The second technique of applying is directly coating the corrosion inhibitors on the drillpipe. 

Direct Treatment. Although batch and continuous treatment are both quite effective, there is a problem with inhibitor waste. When corrosion inhibitors contact the circulating drilling fluid, they are likely to coat the solids in the fluid system (cuttings or other solids). By applying the corrosion inhibitor directly to drillstem components before they are run in the hole, the corrosion inhibitor is the first thing that contacts the exposed metal surface. There are two methods for this type of corrosion inhibitor treatment. 

Microbiocides may be toxic to humans therefore, care must be taken when used. When selecting the microbiocide, the field engineer can obtain pertinent information on chemicals from the service company providing the chemicals. The microbiocide selected must be compatible with the system in which it is being used. Some chemicals such as quaternary amines have dual functions one as microbiocides and the other as film-forming corrosion inhibitors. Insufficient concentrations of this type of chemical may not be enough to coat the whole surface of metal and can cause pitting corrosion. The selection must also depend on chemicals that can produce the desired control in minimum time limits and... 

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