| 摘要 |
515,582. Making emulsions. GOMM, A. S., and IMPERIAL CHEMICAL INDUSTRIES, Ltd. June 7, 1938, No. 16892. [Class 1 (i)] [Also in Group IV] Dispersions of ethylene polymers or derivatives thereof, or ethylene interpolymers in aqueous media are made by dissolving the substances in a volatile organic solvent immiscible or sparingly miscible with water, emulsifying the solution in an aqueous medium in the presence of an emulsifying agent and/or in the presence of the components thereof, if desired in the presence of a protective colloid, and then removing the volatile solvent. Preferably the polymer is dissolved in hot or boiling solvent, the emulsifying agent or compounds added to the solution, and during agitation at an elevated temperature there'is added hot water or an aqueous solution containing an amount of the emulsifying agent or compounds thereof, or the initial solution may be. added to the hot water or aqueous solution. The emulsion is then maintained hot, e.g., about 60-80‹C., agitated and a current of gas, e.g., nitrogen or air is passed through or over the liquid. This gas'is preferably moist, to avoid undue loss of the aqueous phase. If desired, the emulsion may be homogenized or treated in a colloid mill. Violent agitation of the emulsion should be avoided, as tending to cause coagulation. Suitable solvents include benzene, toluene, xylene, petroleum ether, trichloroethylene or other halogenated hydrocarbons. Emulsifying agents include alkali, ammonium or amine salts, e.g., triethanolamine or cyclohexylamine, of aliphatic acids containing over 6 carbon atoms or mixtures obtained from animal fats or oils or from chinawood oil, castor oil, linseed oil or soya bean oil, e.g., stearic, oleic, and hydroxystearic or linseed oil acids. Mixtures of the potassium and triethanolamine salts may be used. Similar salts of sulphuric esters of aliphatic alcohols containing over 6 carbon atoms, e.g., sperm oil alcohols or dodecyl alcohol, or other sulphonated derivatives of aliphatic compounds, e.g., the sodium salt of oleyl-panisidine sulphonic acid may also be used. Suitable protective colloids include casein, glue, gelatine, gum arabic and alkylated celluloses Examples describe the preparation of emulsions of ethylene polymers, interpolymers of ethylene and methyl methacrylate, ethylene and itaconic acid diethyl ester, and a chlorinated ethylene polymer using the solvents and emulsifying agents specified. The dispersions may be used for treating fabrics, paper, wood, glass, metals and 'like materials. Specifications 274,611, [Class 2 (ii)], 471,590, 481,515, and 497,643, [all in Group IV], are referred to.
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