Applications ethylene oxide

Salmona et al. [66] used El and CIMS to identify benzothiazole derivatives leached into injections by rubber plunger seals from disposable syringes. One of the compounds was used as a rubber vulcanisation accelerator, and four others were formed during syringe sterilisation with ethylene oxide. Applications of hyphenated chemical impact mass-spectrometric techniques are described elsewhere GC-MS (Section 7.3.1.2), for polar and nonpolar volatile organics, SFC-MS (Section 13.2.2) and TLC-MS (Section 7.3.5.4). 

Pharmaceutical and Biomedical Applications. On account of its low toxicity and unique properties, poly(ethylene oxide) is utilized in a variety of pharmaceutical and biomedical appHcations. 

Industrial Applications. Poly(ethylene oxide)s also have numerous industrial uses. 

R. R. Ernst, Industrial Sterilisation Ethylene Oxide Gaseous Sterilisation for Industrial Applications Duke University Press, Durham, N.C., 1973. 

Nuclear Magnetic Resonance (nmr). The nmr analysis has been used in the polymer industry for some time to measure properties such as amount and type of branching, polymerized ethylene oxide content, and hydroxyl content. The same techniques are applicable to waxes, and are used for both characterization and quality control. 

Ethylene Glycol. Well over 50% of the ethylene oxide produced is used in the manufacture of ethylene glycol. Ethylene glycol [107-21-1] is used in two significant applications as a raw mateiial for poly (ethylene teiephthalate) for use in polyester fiber, film, and containers, and as an automotive... 

Decomposition Flame Arresters Above certain minimum pipe diameters, temperatures, and pressures, some gases may propagate decomposition flames in the absence of oxidant. Special in-line arresters have been developed (Fig. 26-27). Both deflagration and detonation flames of acetylene have been arrested by hydrauhc valve arresters, packed beds (which can be additionally water-wetted), and arrays of parallel sintered metal elements. Information on hydraulic and packed-bed arresters can be found in the Compressed Gas Association Pamphlet G1.3, Acetylene Transmission for Chemical Synthesis. Special arresters have also been used for ethylene in 1000- to 1500-psi transmission lines and for ethylene oxide in process units. Since ethylene is not known to detonate in the absence of oxidant, these arresters were designed for in-line deflagration application. 

An appreciation of statistical results can be gained from a study conducted to support the first application of computer control for an ethylene oxide production unit at Union Carbide Corporation in 1958. For the above purpose, twenty years of production experience with many units was correlated by excellent statisticians who had no regard for kinetics or chemistry. In spite of this, they did excellent, although entirely empirical work. One statement they made was ... [ethane has a significant effect on ethylene oxide production.] This was rejected by most technical people because it did not appear to make any sense ethane did not react, did not chemisorb, and went through the reactor unchanged. 

An example of the first type is the emulsion stabiliser as exemplified by sodium oleyl sulphate, cetyl pyridinium chloride and poly(ethylene oxide) derivatives. For a number of applications it is desirable that the latex be thickened before use, in which case thickening agents such as water-soluble cellulose ethers or certain alginates or methacrylates may be employed. Antifoams such as silicone oils are occasionally required. 

The polymers are of interest as water-soluble packaging films for a wide variety of domestic and industrial materials. (Additional advantages of the poly(ethylene oxide)s are that they remain dry to the feel at high humidities and may be heat sealed.) The materials are also of use in a number of solution application such as textile sizes and thickening agents. As a water-soluble film they are competitive with poly(vinyl alcohol) whereas in their solution applications they meet competition from many longer established natural and synthetic water-soluble polymers. 

Kirby (1999) reports two snccessful applications of deflagration flame arresters. In one incident, a deflagration flame arrester was installed near the junction of a collection header from an ethylene oxide process nnit with a flare stack. Although this type of flame arrester was really inappro-... 

A number of gases may decompose (self-react) and propagate flames in the absence of any oxidant provided that they are above minimum conditions of pressure, temperature, and pipe diameter. Common examples are acetylene, ethylene oxide, and ethylene. Some, like acetylene, can decompose in a detonative manner, while ethylene cannot detonate in the absence of an oxidant, whatever the run-up length (CCPS 1993). Thus, detonation arresters must be used for acetylene, but deflagration arresters may be used for ethylene, even for in-line applications. 

Sodium dodecylbenzenesulfonate is undoubtedly the anionic surfactant used in the greatest amount because it is the basic component in almost all laundry and dishwashing detergents in powder and liquid forms. However, alcohol and alcohol ether sulfates are the more versatile anionic surfactants because their properties vary, with the alkyl chain, with the number of moles of ethylene oxide added to the base alcohol and with the cation. Consequently, alcohol and alcohol ether sulfates are used in almost all scientific, consumer, and industrial applications. 

The polyoxyethylene group is obtained by addition of ethylene oxide to fatty alcohols, mostly with an alkalic catalyst such as NaOH or NaOCH3, giving a broad polyoxyethylene oxide distribution. For special applications the ethoxyl-ation can be catalyzed by Lewis acids [11] to achieve a narrow range distribution. Other narrow range catalysts can also be used to improve certain properties. 

The chemically reactive gases ethylene oxide (CH2)20, and formaldehyde (methanal, H.CHO) possess broad-spectrum biocidal activity, and have found application in the... 

The sterilization processes described in the Ph Eur are preferred, especially terminal sterilization in the final container alternative processes have to be justified. All sterilization processes will need to be described and appropriate in-process controls and limits included. Where Ph Eur prescriptions are followed, there should be a statement to this effect in the application. Most of this information should be discussed in the development pharmaceutics section. Reference is made to the specific guidelines on ethylene oxide sterilization and irradiation sterilization, which are discussed further below. The possibility of parametric release for terminal processes such as saturated steam and irradiation is mentioned (see below). For all sterile products there should be a sterility requirement included in the finished product specification regardless of the outcome of validation studies. 

As a test, surfactant slug flow experiments were performed in clayey sandpacks with and without the injection of a desorbent behind the micellar slug. Results show that a substantial decrease in surfactant retention is obtained in calcic environment by such an additive. Likewise, the ethoxylated cosurfactant in the micellar slug can be remobilized simultaneously with sulfonatewithout any change in its ethylene oxide distribution. The application of the RST to sulfonate/ ethoxylated alkylphenol mixtures explains semi-quantitatively the relationship between their properties and composition. 

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