Malodorants liquids

Colourless malodorous liquids that are spontaneously flammable in air and react violently with water... 

Caution. Because pyridine is a carcinogenic and malodorous liquid and CO is a toxic gas, all the operations should be performed in a well-ventilated fume hood. 

Dimethyl(pentafluorophenyl)arsine is a colorless, malodorous liquid which has a nmr spectrum in dichloromethane consisting of a triplet centered at t8.51 with /PH = 1.1 Hz. A methyl iodide derivative of the arsine can be prepared by refluxing 1.7 g of the arsine with 15 ml of methyl iodide for 2 hr. After evaporation of the solvent and recrystallization of the product from a dichloromethane-benzene mixture, a colorless compound which melts at 167-168° is obtained. The nmr spectrum of the methyl iodide derivative is a triplet at t7.16 (Jfh = 1.4 Hz) in dichloromethane, and the infrared spectrum (Nujol mull) contains strong peaks at 1080 and 980 cm characteristic of the CeFs group. Anal, (done on the methyl iodide derivative). Calcd. for C9H9-FsAsI C, 26.09 H, 2.17 1, 30.68. Found C, 25.5 H, 2.21 I, 30.1. 

Caution. [ 2,2-Dimethyl-l-( trimethylsiloxy )propylidene]( trimethyl-silyl)phosphine, a malodorous liquid, is extremely sensitive to moisture and ignites in air. Therefore, all procedures must be carried out under an atmosphere of dry argon in a well-ventilated fume hood. 

Although a process of purification is not always applied to these crude oils, it is important and sometimes highly profitable to subject the crude product to a process of rectification. By rectification is meant a redistillation of the oil with steam, this procedure affecting a moderate separation of the undesirable substances which may have been formed. The substances which detract from the odor of the oil are usually left behind in the apparatus as a heavy, malodorous liquid slightly resinous in character. Rectification usually results in a fine, finished product, free from foreign odors, and leaves an oil much more presentable in color as well as in odor and taste. 

Tellurophene is a light yellow malodorous liquid having values of boiling point (b.p.), melting point (m.p.), density (rf4), refractive index (wD),... 

Liquid Fabric Softeners. The principal functions of fabric softeners are to minimize the problem of static electricity and to keep fabrics soft (see Antistatic agents). In these laundry additives, the fragrance must reinforce the sense of softness that is the desired result of their use. Most fabric softeners have a pH of about 3.5, which limits the materials that can be used in the fragrances. For example, acetals cannot be used because they break down and cause malodor problems in addition, there is the likelihood of discoloration from Schiff bases, oakmoss extracts, and some specialty chemicals. Testing of fragrance materials in product bases should take place under accelerated aging conditions (eg, 40°C in plastic bottles) to check for odor stabiUty and discoloration. 

The majority of these materials are organic sulfur compounds that may also contain an odor intensifier. These chemicals are generally volatile liquids at room temperature with odors that are detectable at very low levels. Under normal battlefield conditions, these materials do not pose a serious danger to the life of an exposed individual and do not produce any permanent injury. Since approximately 0.2% of the population is unable to detect odors (anosmic), compositions may contain multiple malodorant components. 

Malodorants are primarily an inhalation hazard. Aerosols and vapors are extremely foul smelling at low concentrations but are otherwise relatively nontoxic. However, exposure to bulk liquid or solid agents may be hazardous through skin absorption, ingestion, and introduction through abraded skin (e.g., breaks in the skin or penetration of skin by debris). 

Munition grade agents typically consist of at least one malodorant agent (10-90%) and an odor intensifier (0.5-5%) dissolved in a liquid carrier. Solvents include volatile hydrocarbons, plant/vegetable oils, and water. Solvents typically pose minimal toxic hazards themselves. Compositions are typically colorless to yellow liquids. As the agent ages and decomposes it may discolor and become brown. 

Physical Properties. Thiophosgene [463-71-8] (thiocarbonyl chloride), CSC, is a malodorous, red-yellow liquid (bp 73.5°C, slightly soluble with decomposition in water, but it is soluble in ether and various organic solvents. 

Caution. Pentacarbonyliron(O) is a toxic, volatile liquid. It is sensitive to light and heat and can be pyrophoric in air. Carbon monoxide is evolved during the course of the synthesis. Diphenylphosphine, methyldiphenylphos-phine, and tributylphosphine are malodorous, air-sensitive, and toxic liquids. All manipulations must be carried out in a well-ventilated fume hood. 

Odor masking does little or nothing to control malodors it merely covers them up. Many materials used in masking odors are aldehydes, which are very chemically reactive and usually comprise the top note of a fragrance. Odor masking is used in many areas of household, industrial, and institutional use via products that mask such malodors as pel smells, smoke, cooking, and numerous other odors. The forms by which masking is executed vary, and can be solid, liquid, and aerosol. 

Tetramethyl tellurium is a malodorous, pyrophoric, yellow-orange liquid. Pure tetramethyl tellurium is extremely pyrophoric and sometimes explodes on contact with air. 

Caution. Sodium and particularly potassium react violently with water and may ignite in air. The incrustations of potassium may be explosive only potassium with little or no incrustation should be cut, and care should be taken to ensure anhydrous conditions. Sodium-potassium alloy as well as malodorous tris(trimethylsilyl)phosphine are pyrophoric and extremely sensitive to moisttve. Therefore the entire procedure must be carried out in an atmosphere of dry argon in a well-ventilated fume hood. In case of emergency a sand bath should be available to catch the liquid alloy. 1,2-Dimethoxyethane and tetrahydrofiiran (THF ) may form explosive peroxides. Only fresh, peroxide-free material should be used. 

The term ionizing wet scrubber was first used by the Ceilcote Co., located in Berea, Ohio, and has found wide application in the air pollution control field. This system is a proven means for the removal of pollutants from industrial process gas streams. The IWS combines the established principles of electrostatic particle charging, image force attraction, inertial impaction, and gas absorption to collect submicron solid particles, liquid particles, and noxious and malodorous gases simultaneously. The IWS system requires little energy and its collection efficiency is high for both submicron and micron size particles. 

The market has also migrated towards consumer-friendly products that reduce fabric wrinkling and dramatically cut/eliminate ironing time [180,182,194,195], Polymers have also been employed to build rheology (or stmcture) in various liquid formulations, with the objective of improved product aesthetics (through the suspension of actives or visual cues) [196], Fragrance encapsulation and additives for masking malodors have also become topics of much interest [197,198],... 

Hexamethylcyclotrisilthiane is a white, waxy solid which melts at 17° to a colorless liquid, b.p. 60° at 0.3 torr, n °, 1.5530, with a singlet peak at t9.3 1 in the proton n.m.r. spectrum. It is exceedingly malodorous and sensitive to water.9 The cyclotrisilthiane is thermally unstable, undergoing ring contraction at about 200° to tetramethylcyclodisilthiane. 

For all these reasons, it is useful to develop, when possible, a gas-liquid chromatographic headspace analysis for the malodorous compound, although often it is present in very low concentration. 

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