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Ethylene oxide condensates have been

The alkylphenol ethylene oxide condensates have been the most widely produced nonionic detergent. These condensates are solubilized by the ethylene oxide units forming hydrates with water. Compared with all other materials that dissolve in water, these products show an apparent anomaly their solutions are completely clear in the cold, but when heated they become turbid and, if the temperature is raised sufficiently, separation into two phases can take place. This is explained by the fact that at an elevated temperature the hydrates are destroyed. [Pg.140]

Neolan Salt P, an anionic product. Palatine Fast Salt O, a fatty acid ethylene oxide condensate, and Dispersol A, an aliphatic ethylene oxide condensate, have been recommended as assistants capable of permitting... [Pg.440]

A single-bath method can be used if desired. The dyes are dissolved separately and added to the dyebath which already contains an ethylene oxide condensate which acts as an anti-precipitant. The dyebath is adjusted to pH 5 to 5-5 with acetic acid and sodium acetate and the goods are entered at 40 to 45°C (104 to 113°F). A period of 45 minutes is taken to raise the temperature to the boil, at which it is maintained for one hour. Alternatively, the acrylic fibre may be dyed first and then the same liquor is neutralized and the cellulosic fibre is dyed. Application of a cationic fixing agent improves wet fastness of direct dyes but copper after-treatment should be avoided because this can have an adverse effect on the light fastness of the cationic dye. Very good fastness is obtained if, after the acrylic component has been dyed, the cellulosic fibre is brought to shade with vat dyes. [Pg.584]

Poly(ethylene oxide). The synthesis and subsequent hydrolysis and condensation of alkoxysilane-terniinated macromonomers have been studied (39,40). Using Si-nmr and size-exclusion chromatography (sec) the evolution of the siUcate stmctures on the alkoxysilane-terniinated poly(ethylene oxide) (PEO) macromonomers of controlled functionahty was observed. Also, the effect of vitrification upon the network cross-link density of the developing inorganic—organic hybrid using percolation and mean-field theory was considered. [Pg.329]

Some types of reactions involving gases that have been studied in IFs are hydrogenations [16, 25-37 ], oxidations [38, 39], and hydroformylations [25, 40 5]. In addition, some dimerizations and allcylations may involve the dissolution of condensable gases (e.g., ethylene, propylene, isobutene) in the IF solvent [46-50]. [Pg.89]

Freeder, B. G. et al., J. Loss Prev. Process Ind., 1988, 1, 164-168 Accidental contamination of a 90 kg cylinder of ethylene oxide with a little sodium hydroxide solution led to explosive failure of the cylinder over 8 hours later [1], Based on later studies of the kinetics and heat release of the poly condensation reaction, it was estimated that after 8 hours and 1 min, some 12.7% of the oxide had condensed with an increase in temperature from 20 to 100°C. At this point the heat release rate was calculated to be 2.1 MJ/min, and 100 s later the temperature and heat release rate would be 160° and 1.67 MJ/s respectively, with 28% condensation. Complete reaction would have been attained some 16 s later at a temperature of 700°C [2], Precautions designed to prevent explosive polymerisation of ethylene oxide are discussed, including rigid exclusion of acids covalent halides, such as aluminium chloride, iron(III) chloride, tin(IV) chloride basic materials like alkali hydroxides, ammonia, amines, metallic potassium and catalytically active solids such as aluminium oxide, iron oxide, or rust [1] A comparative study of the runaway exothermic polymerisation of ethylene oxide and of propylene oxide by 10 wt% of solutions of sodium hydroxide of various concentrations has been done using ARC. Results below show onset temperatures/corrected adiabatic exotherm/maximum pressure attained and heat of polymerisation for the least (0.125 M) and most (1 M) concentrated alkali solutions used as catalysts. [Pg.315]

Several ethylene oxides containing one or more polar atoms on carbon atoms adjacent to the epoxide ring have been condensed with alcohols under various conditions. Greatest attention has been given to opiohlorohydrin in this connexion. [Pg.151]

Alkenylmagneaium bromides have been reported to condense with ethylene oxide. Vinyl- and taobutenylmagneeium bromide, for example, give the expected y.Sunsaturated alcohols in good yield (Eq. 822). but fj-styrylmagnesium bromide reacts poorly. 164... [Pg.205]

A number of other metallic halide salts have been found to condense with ethylene oxide, propylene oxide, or epichlorohydrin in a similar fashion (Eq. 662). Among them are phosphorus trichloride/ 7- a 17 bismuth trichloride,1SM arsenic trichloride,1000 silicon tetrachloride/7 1 titanium tetrachloride/ 09 16,7 beryllium chlorido/189 and Won trifluoride.401 Depending on their reactivity, on the reactant ratio, and... [Pg.231]

In conclusion of the present section, attention may he directed to two other strong mineral acids that have been condensed with ethylene oxides nitric acid and perchloric acid. These reagents, provided they are ueed as cold dilute aqueous solutions to avoid oxidative reactions, give 1,2-diol monoesters. [Pg.459]

Among the carbonylative cycloaddition reactions, the Pauson-Khand (P-K) reaction, in which an alkyne, an alkene, and carbon monoxide are condensed in a formal [2+2+1] cycloaddition to form cyclopentenones, has attracted considerable attention [3]. Significant progress in this reaction has been made in this decade. In the past, a stoichiometric amount of Co2(CO)8 was used as the source of CO. Various additive promoters, such as amines, amine N-oxides, phosphanes, ethers, and sulfides, have been developed thus far for a stoichiometric P-K reaction to proceed under milder reaction conditions. Other transition-metal carbonyl complexes, such as Fe(CO)4(acetone), W(CO)5(tetrahydrofuran), W(CO)5F, Cp2Mo2(CO)4, where Cp is cyclopentadienyl, and Mo(CO)6, are also used as the source of CO in place of Co2(CO)8. There has been significant interest in developing catalytic variants of the P-K reaction. Rautenstrauch et al. [4] reported the first catalytic P-K reaction in which alkenes are limited to reactive alkenes, such as ethylene and norbornene. Since 1994 when Jeong et al. [5] reported the first catalytic intramolecular P-K reaction, most attention has been focused on the modification of the cobalt catalytic system [3]. Recently, other transition-metal complexes, such as Ti [6], Rh [7], and Ir complexes [8], have been found to be active for intramolecular P-K reactions. [Pg.175]

Aldehydes have been used to condense with o-phenylenediamines, o-nitroanilines, or ethylene diamines to afford benzimidazoles and imidazolines. Either an oxidation or a reduction process may be required during the annelation depending on the oxidation state of the starting material. To prepare imidazolines or benzimidazoles from aldehydes and diamines under anaerobic conditions, the system I2/KI/K2CO3/H2O can be used to oxidize a C-N single bond to a double bond (Scheme 302) <2006TL79>. Oxidant K3Fe(CN)5 has also been used to promote similar processes... [Pg.300]


See other pages where Ethylene oxide condensates have been is mentioned: [Pg.317]    [Pg.506]    [Pg.397]    [Pg.322]    [Pg.14]    [Pg.415]    [Pg.208]    [Pg.63]    [Pg.62]    [Pg.25]    [Pg.92]    [Pg.80]    [Pg.664]    [Pg.482]    [Pg.574]    [Pg.769]    [Pg.460]    [Pg.51]    [Pg.129]    [Pg.438]    [Pg.443]    [Pg.415]    [Pg.41]    [Pg.186]    [Pg.490]    [Pg.33]    [Pg.5190]    [Pg.123]    [Pg.92]    [Pg.438]    [Pg.443]    [Pg.2021]   


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