Showing papers on "Ether published in 1979"

Ethyl acetate as a substitute for diethyl ether in the formalin-ether sedimentation technique.

Abstract: Ethyl acetate appears to be a satisfactory subsitute solvent for diethyl ether in the Formalin-ether sedimentation technique. In comparative studies, concentration of organisms with ethyl acetate was equal to or greater than that with diethyl ether. No distortion or alteration of morphology was observed with eigher solvent, and preparations were comparable in appearance and ease of examination. In addition, ethyl acetate is less flammable and less hazardous to use than diethyl ether.

Host--guest complexation. 16. Synthesis and cation binding characteristics of macrocyclic polyethers containing convergent methoxyaryl groups

Abstract: The syntheses and free energies of association of 12 new macrocyclic ligand systems (hosts) with alkali metal and ammonium and alkylammonium picrates in CdCl/sub 3/ are reported at 25/sup 0/C Ten of the hosts were composed of 4-methylanisole units (abbreviated AN) incorporated into the macroring by substitution at their 2,6 positions by CH/sub 2/O(MO) units, or by direct attachment to other AN units at their 2,6 positions The macrorings were completed with CH/sub 2/CH/sub 2/ (E) units and additional ether oxygens (O) The other two ligand systems were (AN/sub 2/DP(OEOEO)/sub 2/E (39) and DP(OEOEO)/sub 2/E (40), in which DP = 5,5'-dimethyldiphenyl substituted in the 2,2' positions with O and the 3,3' positions with either H or 2-methoxy-5-methylphenyl (AN) groups These systems were compared with model macrocyclic ethers not containing anisole units General ion selectivity of each ligand system was measured by the difference in free energies between the best and poorest bound of the picrate salts, -delta(deltaG/sub max/) (kcal/mol) These results demonstrate that, when the oxygens of anisole units are held in sterically enforced conformations which make the unshared electron pairs provide the lining of partially spherical cavities, the anisole units become better and more selective complexers of anions thanmore » the now classic crown ether compounds Such conformations are observed only when m-teranisyl units are incorporated in macroring systems 3 tables« less

Modified nonionic cellulose ethers

Abstract: Cellulose ethers are disclosed which have sufficient nonionic substitution to render them water soluble and which are further modified with a C 10 to C 24 long chain alkyl group in an amount between about 0.2% by weight and the amount which makes them less than 1% soluble in water. Hydroxyethyl cellulose is a preferred water-soluble cellulose ether for modification according to the invention. These products exhibit substantially improved viscosifying effect compared to their unmodified cellulose ether counterparts and also exhibit some surface activity.

Sensitizers for photopolymerization

Abstract: Aromatic-aliphatic ketones of the formulae I, II, III or IV ##STR1## wherein n is 1 or 2, Ar is an aryl radical, R1 and R2 are monovalent aliphatic, cycloaliphatic or araliphatic radicals, R3 is a direct bond or a divalent organic radical, X is a hydroxyl or amino group or the monovalent etherification or silylation products thereof, and X' is a divalent amino, ether or silyloxy group, Y is a direct bond or CH2 and Z is O, S, SO2, CH2 or C(CH3)2, are suitable sensitizers for the photopolymerization of unsaturated compounds and for the photochemical crosslinking of polyolefins. Some of these compounds are novel and can be obtained by methods analogous to those for obtaining the known compounds of this type.

Vulcanizable fluorinated copolymers

Abstract: Vulcanizable copolymers of tetrafluoroethylene, perfluoromethyl perfluorovinyl ether and a cyano-substituted perfluorovinyl ether such as perfluoro-(8-cyano-5-methyl-3,6-dioxa-1-octene) and perfluoro-(9-cyano-5-methyl-3,6-dioxa-1-nonene) and elastomeric vulcanizates thereof.

The Solvent Extraction of Bivalent Metal Picrates by 15-Crown-5, 18-Crown-6, and Dibenzo-18-crown-6

Abstract: The overall extraction equilibrium constants (Kex) for the 1:1:2 complexes of 15-crown-5 (15C5), 18-crown-6 (18C6), and dibenzo-18-crown-6 (DB18C6) with several bivalent metal picrates between benzene and water have been determined at 25 °C. The Kex sequences of the bivalent metal ions with 15C5, 18C6, and DB18C6 are Pb2+>Sr2+>Ba2+>Ca2+, Pb2+>>Ba2+=Sr2+>Hg2+>Ca2+, and Pb2+>Hg2+>Sr2+>Ca2+ respectively. To clarify the role of the crown ether in the extraction process, the three constituent equilibria have been investigated: the stability and the extractability of the bivalent metal ion-crown ether complex, and the distribution coefficient of the crown ether. The extractability of the bivalent metal ion-crown ether complex about the same bivalent metal ion increases with increasing size of the crown ether, and appears to be dependent on the chemical nature of the bivalent metal ion trapped in the cavity of the crown ether.

Metabolism of Chlorodiphenyl Ethers and Irgasan® DP 300

Abstract: 1. In the rat chlorodiphenyl ethers are metabolized via two routes. The predominant reaction is aromatic hydroxylation; scission of the ether bond is a minor metabolic process.2. In all cases, primary hydroxylation takes place ortho and meta to the ether bond. Ortho-hydroxylation leads to the formation of 'predioxins' in cases where the parent compounds contain a chlorine atom in one of the ortho positions in the second ring.3. 5-Chloro-2-(2,4-dichlorophenoxy)phenol (Irgasan DP 300), a compound that meets the structural requirements of a predioxin, did not yield chlorodibenzo-p-dioxins or hydroxylated derivatives thereof.4. Irgasan DP 300 is excreted unchanged in faeces and urine (partly conjugated) but is also hydroxylated to five different monohydroxy metabolites which were found in urine; three of these were also present in faeces. As a result of scission of the ether bond 2,4-dichlorophenol occurred in urine and faeces, and 4-chlorocatechol in urine.5. Neither in the case of Irgasan DP 300, nor in tha...

Selective desilylation of bis(trimethylsilyl)acetylenes

Abstract: Substituted acetylenic carbinols such as (2), (5), and (6) are obtained from the reaction of carbonyl compounds with the potassium or lithium salts of trimethylsilyacetylenes; these are prepared either by the in situ cleavage of bis(trimethylsilyl)acetylenes with 1–10 mol% KF–18-crown-6 ether or by the quantitative monodesilylation of bis-silylacetylenes with MeLiLiBr complex.

Blends of poly(aryl ether) resins and polyetherimide resins

Abstract: Described herein are molding compositions of blends of a poly(aryl ether) resin and a polyetherimide resin. These compositions have improved environmental stress crack resistance.

[Testicular atrophy of mice induced by ethylene glycol mono alkyl ethers (author's transl)].

Abstract: Toxicities of ethylene glycol (EG) and 6 ethylene glycol mono alkyl ethers administered orally were studied. Mice were given various doses (62.5, 125, 250, 500, 1,000, 2,000 and 4,000 mg/kg body weight) of the compounds daily for 5 days/week, for 5 weeks. High doses of ethylene glycol mono methyl ether (EGM), ethylene glycol mono methyl ether acetate (EGMA), ethylene glycol mono ethyl ether (EGE) and ethylene glycol mono ethyl acetate (EGEA) produced marked testicular atrophy and leucopenia. Dose-responce relation was found in these effects. EGM was more effective than EGE, while ethylene glycol mono butyl ether and ethylene glycol mono phenyl ether had but slight effect and EG had no detectable action on testis and leucocytes. Toxic doses being expressed as mg/kg body weight, esterification seemed to weaken the atrophic action of EGM and EGE, but when expressed as mol/kg, significant difference was found neither between EGM and EGMA nor between EGE and EGEA. The mechanism of testicular atrophy induced by low ethylene glycol mono alkyl ethers is likely to be an inhibitory action on cell division.

Halogenncontaining resin composition

Abstract: PURPOSE:To prepare a halogen-containing resin composition having high stability to light and heat, and low toxicity, and useful as food containers, packaging materials, etc., by adding a carboxylic acid Zn salt, a mono-organophosphoric acid salt, a di-organophosphoric acid salt, and an organic phosphite, to a halogen-containing resin. CONSTITUTION:A halogen-containing resin composition composed of 100 parts by weight of a halogen-containing resin such as vinyl chloride resin, and pref. 0.5-3 parts of a stabilizer comprising (A) a carboxylic acid zinc salt such as zinc stearate, (B) mono-organophosphoric acid salt of formula I (R1 is alkyl, aryl, aralkyl, alkylaryl, alkyl having an ether bond; M is two alkali metals, an alkaline earth metal, dialkyltin), e.g. monooctyl phosphoric acid barium salt, (C) di-organophosphoric acid salt of formula II (R2,3 are same as R1;M' is alkali(ne earth) merth) metal, dialkyltin; a is 1,2), e.g. dioctyl phosphoric acid zinc salt, and (D) an organic phosphite, e.g. octyldiphenyl phosphite.

Clear cosmetic sticks

Abstract: A composition for use as a base in clear cosmetic sticks comprises water, lower alkyl ester of fatty acid, propylene glycol, sodium salt of fatty acid, polyoxypropylene ether of a long chain alcohol, polyoxyethylene ether of a long chain alcohol, and polyoxyethylene-glucose-fatty acid ester.

Elektronenstruktur von Alkyl‐aryl‐ und Alkyl‐vinyl‐ethern

Abstract: Um das Ausmas der Konjugation zwischen π-Elektronen der CC-Doppelbindung und freien Elektronenpaaren am O-Atom α, β-ungesattigter Ether zu ermitteln, wurden die Photoelektronenspektren einer Anzahl von Alkyl-aryl-ethern 1–3 aufgenommen und mit den Spektren von Alkyl-vinyl-ethern 5 verglichen. Die Ergebnisse lassen sich mit Hilfe von Orbitalkorrelationsdiagrammen vollstanding interpretieren, sofern man energetisch hochliegende σ-Orbitale geeigneter Symmetrie in die Betrachtung einbezieht. Sterisch gehinderte Alkyl-aryl-ether nehmen eine perpendikulare Konformation ein, die bei sterisch nicht gehinderten Verbindungen wie etwa Anisol als zweite weniger stabile Form gefunden wird. Im Fall der Alkyl-vinyl-ether uberwiegt aufgrund einer nichtbindenden Wechselwirkung die s-cis-Konformation bei sterisch nicht gehinderten Ethern, wahrend sonst die s-trans-Konformation bevorzugt wird. Durch die Aufnahme von Photoelektronenspektren bei Temperaturen bis 510 k lassen sich die Energieunterschiede zwischen den verschiedenen Konformeren abschatzen. Die Ergebnisse der PE-Untersuchungen Konnen zur Interpretation von Reaktionen α,β-ungesattigter Ether herangezogen werden. Electronic Structure of Alkyl Aryl and Alkyl Vinyl Ethers For the evaluation of the interactions between π electrons of the CC double bond and lone Pairs at the 0 atom of α, β-unsaturated ethers p. e. spectra of some alkyl aryl ethers 1–3 were recorded and compared with those of alkyl vinyl ethers 5. The data could be interpreted by means of orbital correlation diagrams provided the interaction with energetically high-lying σ orbitals of the correct symmetry was taken into account. Sterically hindered alkyl aryl ethers were found to exist in a perpendicular conformation; in sterically unhindered ethers like anisole a less stable isomer having this conformation was detected. In the case of alkyl vinyl ethers non-bonding interactions favour the s-cis conformation, whereas sterically hindered molecules of this type prefer the s-trans form. From p. e. spectra at higher temperatures (up to 510 K) the relative conformational energies are estimated. The results of the p. e. analysis are used for the interpretation of some reactions of α,β-unsaturated ethers.

Method for making aromatic ether imides

Abstract: A method for making aromatic ether imides is provided by effecting the displacement of reactive radicals on a phthalimide nucleus with a mono- or bis-alkali metal phenoxide in the presence of a nonpolar solvent and a phase transfer catalyst, such as a tetra-ammonia salt. The aromatic ether imides made by the present invention are useful intermediates for making aromatic ether anhydrides and aromatic bis(ether anhydrides).

Polyaryl ether sulfone semipermeable membrane and process for producing same

Abstract: A semipermeable membrane made of a polyaryl ether sulfone comprised of recurring units represented by the general formula (I): ##STR1## wherein X, X', X" and X"' are non-dissociative substituents, and l, m, n and o are integers of from 0 to 4. The membrane, which is composed of a single continuous polymer phase, has pores of a diameter increasing progressively and continuously from the surface layers to the center portion thereof. The membrane is prepared by the process wherein: the polyaryl ether sulfone is dissolved in a mixed solution to form a dope of the polyaryl ether sulfone; the polyaryl ether sulfone dope is extruded to form a fiber or film and, then; both sides of the fiber or film are contacted with a liquid miscible with the mixed solvent but incapable of dissolving the polyaryl ether sulfone to remove substantially all the mixed solvent from the fiber or film.

Gasoline-ethanol fuel mixture solubilized with methyl-t-butyl-ether

Abstract: Crude ethyl-t-butyl ether is used as a cosolvent for hydrous ethanol in gasoline fuel mixtures The ether solubilizes grain alcohol in all proportions in low aromatic content gasolines