Patent GB-993469-A (GB)
Title: Uniform particle size resins
IPC: C08F18/08
Filed: 1962-12-07
Abstract: Vinylidene resins in the form of spherical particles of substantially uniform particle size are prepared by a method which comprises one or more monomers containing a CH2=C< group, optionally in admixture with up to 50% by weight of other copolymerizable olefinically unsaturated monomers, in aqueous emulsion with agitation and in the presence of a water-insoluble soap which is a lithium or polyvalent metal salt of a saturated, unsaturated or substituted fatty acid.  Specified vinylidene monomers are vinyl aromatic compounds and the ring and alpha substitution products thereof, vinylidene halides, esters of acrylic and alpha-substituted acrylic acids, and vinyl and isopropenyl esters.  Other monomers which may be present include vinyl and vinylidene halides, chlorotrifluoroethylene, conjugated dienes, nitriles of unsaturated acids, esters of maleic, fumaric, itaconic, methylene malonic, citraconic and mesaconic acids, mono-olefins, vinyl and allyl esters and ethers, and vinyl and isopropenyl ketones.  Specified soaps are the lithium, barium, calcium, strontium, magnesium, beryllium, zinc, cadmium, aluminium, tin, lead and titanium salts of octanoic, stearic, oleic, linoleic, ricinoleic, palmitic and abietic acids. Polymerization may be effected in the presence of free radical initiators, e.g. alkali metal and ammonium persulphates, hydrogen peroxide, potassium perphosphate, azo compounds and redox systems, or ultraviolet light or high-energy radiation, and in the presence of buffers, e.g. ammonia, ammonium bicarbonate and sodium bicarbonate.  The insoluble soaps may be formed in situ, e.g. from barium hydroxide and lauric acid.  Long lists of suitable monomers and comonomers are given and examples describe the polymerization of vinyl acetate using (I) barium laurate; (II) aluminium myristate, aluminium stearate, calcium laurate, calcium myristate, calcium palmitate, calcium stearate, lead laurate, lead stearate, magnesium laurate, magnesium myristate or magnesium stearate; and (III) mixtures of calcium and magnesium laurates, barium laurate and stearate, cadmium stearate and calcium laurate, or lead oleate and lithium laurate; of vinyl acetate and (IV) diethyl fumarate using calcium stearate, (V) ethyl acrylate using magnesium laurate, (VI) diethyl maleate using lithium laurate, and (VII) diethyl itaconate using lead stearate; of (VIII) ethyl acrylate using lithium stearate; of (IX) methyl acrylate or a -chloracrylate using calcium stearate; of (X) n-butyl acrylate using calcium palmitate; of (XI) stearyl methacrylate using calcium palmitate; of ethyl methacrylate using (XII) aluminium myristate, aluminium stearate, calcium laurate, calcium myristate, calcium palmitate, calcium stearate, lead laurate, lead stearate, magnesium laurate, magnesium myristate or magnesium stearate; and (XIII) mixtures of calcium and magnesium laurates, barium laurate and stearate, cadmium stearate and calcium laurate, or lead oleate and lithium stearate; of (XIV) methyl methacrylate and ethyl acrylate using calcium laurate; of (XV) methyl methacrylate, ethyl acrylate and acrylic acid using magnesium laurate; of (XVI) methyl methacrylate and styrene using calcium laurate; of vinylidene chloride using (XVII) barium laurate, and (XVIII) calcium palmitate, lead stearate, cadmium stearate, magnesium myristate, barium laurate or lithium stearate; of vinylidene chloride with (XIX) vinyl chloride using calcium stearate, (XX) ethyl acrylate using magnesium laurate, or methyl methacrylate using lead stearate, and (XXI) acrylonitrile using lithium laurate; of (XXI) styrene or vinyl toluene using barium laurate; of styrene using (XXIII) aluminium myristate, aluminium stearate, calcium laurate, calcium myristate, calcium palmitate, calcium stearate, magnesium laurate, magnesium myristate, magnesium stearate or tetrastearyltitanate; or (XXIV) mixtures of calcium and magnesium laurates, calcium and barium laurates, magnesium and barium laurates, or cadmium and barium stearates; and of styrene with (XXV) vinylidene chloride using lead stearate or barium laurate, methyl methacrylate or acrylonitrile using barium laurate, butadiene using barium laurate or cadmium stearate, or butadiene and acrylonitrile using barium laurate. Specification 627,265 also is referred to.