Amines inhibitors

M3. Marley, E., and Blackwell, B., Interactions of monoamine oxidase inhibitors, amines and foodstuffs. Advan. Pharmaml. Chemothtr. 8, 18.5-239 (1970). 

Marley, E. Blackwell, B. Interactions of monoamine oxidate inhibitors, amines, and food stuffs. Adv Pharmacol and Chemo-Therap, 1970 8 185-239... 

The potency of benzylamine 45 towards wild-type virus is similar to that of BMS-433771 (13) and the unsubstituted analogue. However, the positive effect of a basic amine moiety at C-5 is most effectively demonstrated by the potency that the amine 45 expressed towards the K394R virus that confers resistance to this class of RSV fusion inhibitor. Amine 45 inhibits K394R virus with an EC50 of 20 nM, over 1,000-fold more potent than BMS-433771 (13), a result that supports the hypothesized binding mode [16, 111],... 

Organic inhibitors - amines and other organic chemicals. 

Production media Corrosion inhibitors—amines/high pH... 

Trace levels of unreacted alcohol cause problems in traditional nonionics while all ethoxylated amines have a minimum of two EOs prior to building the chain. Again, an advantage in theory. By also acting as dye transfer inhibitors, amine ethoxylates have a definite advantage over AE. The weak point of ethoxy-... 

The expression is valid in the cases when the products of inhibitor transformation are inactive as inhibitors or initiators. In some special cases, the introduction of the inhibitor (amine) into the oxidized substance does not quench but, by contrast, enhances chemiluminescence (see Chapter 11). 

CH2 CCl2- Colourless liquid, b.p. 32°C, manufactured by the dehydrochlorination of trichloroethane. In the presence of light and air, it decomposes with the evolution of HCI, phosgene, and methanal and deposition of some polyvinylidene chloride. Consequently it must be stored away from light and in the presence of dissolved inhibitors (such as phenols and amines). Under the influence of... 

Corrosion inhibitors partial esters of succinic acid, fatty acids, sulfonates, phenates, amine phosphates. 

Some of the physical properties of fatty acid nitriles are Hsted in Table 14 (see also Carboxylic acids). Eatty acid nitriles are produced as intermediates for a large variety of amines and amides. Estimated U.S. production capacity (1980) was >140, 000 t/yr. Eatty acid nitriles are produced from the corresponding acids by a catalytic reaction with ammonia in the Hquid phase. They have Httie use other than as intermediates but could have some utility as surfactants (qv), mst inhibitors, and plastici2ers (qv). 

The Hofmann elimination route, of which many versions exist, can be carried out at much lower temperatures in conventional equipment. The PX is generated by a 1,6-Hofmaim elimination of amine from a quaternary ammonium hydroxide in the presence of a base. This route gives yields of 17—19%. Undesired polymeric products can be as high as 80% of the product. In the presence of a polymerization inhibitor, such as phenothiazine, DPXN yields can be increased to 50%. 

Patients receiving monoamine oxidase inhibitors (MAOI) as antidepressant therapy have been especially subject to the hypertensive effects of vasoactive amines (52). These dietary amines have also been impHcated as causative agents ia migraine. Other aaturaHy occurring alkaloids (qv) have been recognized for centuries as possessing neurological stimulant and depressant properties. 

AH corrosion inhibitors in use as of this writing are oil-soluble surfactants (qv) which consist of a hydrophobic hydrocarbon backbone and a hydrophilic functional group. Oil-soluble surfactant-type additives were first used in 1946 by the Sinclair Oil Co. (38). Most corrosion inhibitors are carboxyhc acids (qv), amines, or amine salts (39), depending on the types of water bottoms encountered in the whole distribution system. The wrong choice of inhibitors can lead to unwanted reactions. Eor instance, use of an acidic corrosion inhibitor when the water bottoms are caustic can result in the formation of insoluble salts that can plug filters in the distribution system or in customers vehicles. Because these additives form a strongly adsorbed impervious film at the metal Hquid interface, low Hquid concentrations are usually adequate. Concentrations typically range up to 5 ppm. In many situations, pipeline companies add their own corrosion inhibitors on top of that added by refiners. 

Corrosion Inhibitors. The corrosion inhibitors used in diesel fuel ate generally similar to those used in gasoline and, like the latter, produce an effect primarily by surface action. If amine additives ate used for detergency, these may provide some corrosion protection as well. 

Rust inhibitors usually are corrosion inhibitors that have a high polar attraction toward metal surfaces and that form a tenacious, continuous film which prevents water from reaching the metal surface. Typical mst inhibitors are amine succinates and alkaline-earth sulfonates. Rust inhibitors can be used in most types of lubricating oils, but factors of selection include possible corrosion of nonferrous metals or formation of emulsions with water. Because mst inhibitors are adsorbed on metal surfaces, an oil can be depleted of its mst inhibitor. In certain cases, it is possible to correct the depletion by adding more inhibitor. 

Zinc dialkyl dithiophosphates are the primary oxidation inhibitors in combining these functions with antiwear properties in automotive oils and high pressure hydrauhc fluids. Their production volume is followed by aromatic amines, sulfurized olefins, and phenols (22). 

Lubrication oil additives represent another important market segment for maleic anhydride derivatives. The molecular stmctures of importance are adducts of polyalkenyl succinic anhydrides (see Lubrication and lubricants). These materials act as dispersants and corrosion inhibitors (see Dispersants Corrosion and corrosion control). One particularly important polyalkenyl succinic anhydride molecule in this market is polyisobutylene succinic anhydride (PIBSA) where the polyisobutylene group has a molecular weight of 900 to 1500. Other polyalkenes are also used. Polyalkenyl succinic anhydride is further derivatized with various amines to produce both dispersants and corrosion inhibitors. Another type of dispersant is a polyester produced from a polyalkenyl succinic anhydride and pentaerythritol [115-77-5]. 

Oxidation of LLDPE starts at temperatures above 150°C. This reaction produces hydroxyl and carboxyl groups in polymer molecules as well as low molecular weight compounds such as water, aldehydes, ketones, and alcohols. Oxidation reactions can occur during LLDPE pelletization and processing to protect molten resins from oxygen attack during these operations, antioxidants (radical inhibitors) must be used. These antioxidants (qv) are added to LLDPE resins in concentrations of 0.1—0.5 wt %, and maybe naphthyl amines or phenylenediamines, substituted phenols, quinones, and alkyl phosphites (4), although inhibitors based on hindered phenols are preferred. 

In petroleum and oxygenate finish removers, the major ingredient is normally acetone, methyl ethyl ketone [78-93-3], or toluene. Cosolvents include methanol, / -butanol [71-36-3], j -butyl alcohol [78-92-2], or xylene [1330-20-7]. Sodium hydroxide or amines are used to activate the remover. Paraffin wax is used as an evaporation retarder though its effectiveness is limited because it is highly soluble in the petroleum solvents. CeUulose thickeners are sometimes added to liquid formulas to assist in pulling the paraffin wax from the liquid to form a vapor barrier or to make a thick formula. Corrosion inhibitors are added to stabili2e tbe formula for packaging (qv). 

ALkylamines are corrosive to copper, copper-containing alloys (brass), aluminum, 2inc, 2inc alloy, and galvani2ed surfaces. Aqueous solutions of aLkylamines slowly etch glass as a consequence of the basic properties of the amines in water. Carbon or stainless steel vessels and piping have been used satisfactorily for handling aLkylamines and, as noted above, some aLkylamines can act as corrosion inhibitors in boiler appHcations. 

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. 

Monofunctional, cyclohexylamine is used as a polyamide polymerization chain terminator to control polymer molecular weight. 3,3,5-Trimethylcyclohexylamines ate usehil fuel additives, corrosion inhibitors, and biocides (50). Dicyclohexylamine has direct uses as a solvent for cephalosporin antibiotic production, as a corrosion inhibitor, and as a fuel oil additive, in addition to serving as an organic intermediate. Cycloahphatic tertiary amines are used as urethane catalysts (72). Dimethylcyclohexylarnine (DMCHA) is marketed by Air Products as POLYCAT 8 for pour-in-place rigid insulating foam. Methyldicyclohexylamine is POLYCAT 12 used for flexible slabstock and molded foam. DM CHA is also sold as a fuel oil additive, which acts as an antioxidant. StericaHy hindered secondary cycloahphatic amines, specifically dicyclohexylamine, effectively catalyze polycarbonate polymerization (73). 

Amine salts, especially acetate salts prepared by neutralization of a fatty amine with acetic acid, are useflil as flotation agents (collectors), corrosion inhibitors, and lubricants (3,8). Amine acetates are commercially available from a number of suppHers Akzo Chemicals Inc. (Armac) (73) Henkel Corporation (formerly General Mills) (Alamac) (74) Jetco Chemicals Inc. (The Procter Gamble Company) (fet Amine) (75) Sherex (Adogen) (76) and Tom ah Products (Exxon Chemical Company) (Tomah) (77). 

Fatty amines and derivatives are widely used in the oil field, as corrosion inhibitors, surfactants, emulsifying/deemulsrfying and gelling agents (90). 

Primary alkanolamine solutions require a relatively high heat of regeneration. Also excessive temperatures or localized overheating in reboilers cause the MEA to decompose and form corrosive compounds. An inhibitor system, such as the Amine Guard system developed by Union Carbide, is an effective method of corrosion control (52). Inhibitors permit the use of higher (25—35%) concentration MEA solutions, thus allowing lower circulation rates and subsequendy lower regeneration duty. 

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