Patent ES-8603510-A1 (ES)
Title: Process for preparing concentrated acrylic dispersions.
IPC: C08F220/12
Filed: 1982-05-19
Abstract: EP--65253 A An emulsifier system contg., by wt. w.r.t. monomers, 0.01-1% di-6-18 C-alkyl sulpho-succinate, (I), in addn. to 0.01-5% semi-sulphate, (II), of an 8-9 C-alkyl-phenol ethoxylated with 5-50 mol C2H4O, is used in the prepn. of conc. polyacrylate dispersions by the emulsion polymerisation of, by wt., (A) 65-97% 1-8 C-alkyl (meth)acrylate, (B) 0.3-10% 3-5C alpha,beta-mono-olefinically unsatd. mono- and/or di-carboxylic acids and/or their amides and (C) 0-25% styrene, acrylonitrile, vinyl acetate and/or vinyl chloride. Polymerisation takes place in aq. emulsion at pH 2-6, in the presence of standard water-soluble radical-forming initiators, at 30-95 deg. C. - The dispersions are used for finishing leather. The combination of (I) and (II) leads to the formation of stable, speck-free dispersions contg. over 55 wt.% solids. Transparent coatings are obtd., sealing the leather with a tear-free film. EPAB- EP--65253 B An emulsifier system contg., by wt. w.r.t. monomers, 0.01-1% di-6-18 C-alkyl sulpho-succinate, (I), in addn. to 0.01-5% semi-sulphate, (II), of an 8-9 C-alkyl-phenol ethoxylated with 5-50 mol C2H4O, is used in the prepn. of conc. polyacrylate dispersions by the emulsion polymerisation of, by wt., (A) 65-97% 1-8 C-alkyl (meth)acrylate, (B) 0.3-10% 3-5C alpha,beta-mono-olefinically unsatd. mono- and/or di-carboxylic acids and/or their amides and (C) 0-25% styrene, acrylonitrile, vinyl acetate and/or vinyl chloride. Polymerisation takes place in aq. emulsion at pH 2-6, in the presence of standard water-soluble radical-forming initiators, at 30-95 deg. C. - The dispersions are used for finishing leather. The combination of (I) and (II) leads to the formation of stable, speck-free dispersions contg. over 55 wt.% solids. Transparent coatings are obtd., sealing the leather with a tear-free film. (17pp) - EP--65253 B A process for the preparation of a concentrated polyacrylate dispersion by polymerisation of 65-97 percent by weight of acrylic or methacrylic acid esters of alkanols of 1 to 8 carbon atoms, 0.3-10 percent by weight of a B-monoolefinically unsatura-ted monocarboxylic and/or dicarboxylic acids of 3 to 5 carbon atoms and/or their amides, and 0-25 percent by weight of monomers from the group comprising styrene, acrylonitrile, vinyl acetate and vinyl chloride, in aqueous emulsion at pH 2-6 in the presence of 0.01-5.0 percent by weight, based on the monomers of the sulphuric acid half-ester of an adduct of an alkylphenol, alkyl being of 8 or 9 carbon atoms with 5-50 moles of ethylene oxide and of conventional water-soluble free radical initiators at 30-95 deg.C, by the emulsion feed process, wherein 0.01-1 percent by weight based on the monomers of a dialkyl sulphosuccinate, alkyl being of 8 to 18 carbon atoms, is used as an additional emulsifier.  (6pp) USAB- US4424298 A Prepn. of a conc. polyacrylate dispersion consists of polymerisation of 65-97 wt% (meth)acrylic acid ester of 1-8C alkanols, 0.3-10 wt% alpha,beta-monoolefinically unsatd. 3-5C mono- or di-carboxylic acids or their amides and 0-25 wt% monomers chosen from styrene, acrylonitrile, vinyl acetate and vinyl chloride. Reaction takes place in aq. emulsion at pH 2-6 in the presence of 0.01-5.0 wt%, based on the monomers of the sulphuric acid half ester of an adduct of an alkylphenol (having an 8-9C alkyl gp.) with 5-50 moles ethylene oxide and 0.01-1 wt%, based on monomers, of a di 6-18C alkyl sulphosuccinate, and conventional water-soluble free radical initiators at 30-95 deg/C by the emulsion feed process. - The dispersion is free from specks, has low viscosity and produces good sealing on leather surfaces. It is stable and forms glass-clear, craze-free films.  (5pp)r ..ER ALL