摘要:
Acrylic resin dispersions are prepared by a monomer addition process in the presence of a free-radical initiator and an emulsifier, wherein a portion of the emulsifier is dissolved in the initial aqueous phase and the remaining portion in the added monomer phase. The new process decreases the formation of coagulates, reduces the required amount of emulsifier, and allows the preparation of dispersions of resins incorporating a large proportion of units derived from water-soluble monomers, such as carboxylic acids.
摘要:
What are disclosed are methods for making an aqueous dispersion of a synthetic resin copolymer, said dispersion having high pigment binding capacity and adaptable to use in the preparation of printing inks or pastes, said copolymer comprising a predominant amount of water insoluble monomers together with from 3 to 8 percent by weight of an acid component which is a water soluble acid or salt, which method comprises gradually adding said water insoluble monomers, together with a portion of said acid component, to an aqueous medium containing the balance of the acid component in the form of a dissolved water soluble salt; aqueous synthetic resin dispersions made by these methods; and printing inks comprising such an aqueous synthetic resin dispersion which has been neutralized and combined with such an amount of an organic solvent as converts the dispersion into a solution or colloidal dispersion of the synthetic resin.
摘要:
What are disclosed are methods for dispersing a powdered salt-forming synthetic resin in water in the presence of an agent forming a salt with said resin, methods for coating pharmaceutical dosage forms with a dispersion made by such a method, and powdered mixtures of a salt forming resin and salt forming agent for dispersion in water.
摘要:
Coating materials for pharmaceutical dosage forms contain, besides the conventional liquid or solid additives for pharmaceutical coatings, a binder comprising a synthetic polymer, prepared by emulsion polymerization, having 5 to 100% by weight of units derived from monomers of the formula ##STR1## wherein R.sub.1 is a hydrogen atom or a lower alkyl group, R.sub.2 is an alkylene or aralkylene group having at least 3 carbon atoms in the chain between the amino nitrogen and the ester oxygen atom of which at least one is tertiary or quaternary, and R.sub.3 and R.sub.4 are lower alkyl radicals or together with the amino-nitrogen atom form a heteroaliphatic ring, and, optionally, additional comonomer units.
摘要:
What are disclosed are plastisols of copolymers of methyl methacrylate with from 0.1 to 10 weight percent of itaconic acid or of itaconic acid anhydride, which copolymers have a glass transition temperature above 50.degree. C., a degree of polymerization higher than 400 and an average particle size ranging from 0.1 to 500 microns and contain, per 100 parts by weight of the copolymer, from 100 to 1000 parts by weight of an organic plasticizer compatible with the copolymer, and optional fillers and further conventional additives.
摘要:
What is disclosed is a method for making a substantially salt free solid polymer product from an emulsion polymer prepared with the aid of a free emulsifier acid having a pKa in the 1.0 to 4.5 range, the dispersion so obtained being precipitated by the addition thereto of a strong acid.
摘要:
What are disclosed are a method for making an emulsion polymer by polymerizing water insoluble free-radically polymerizable monomers, or monomer mixtures predominantly comprising such monomers, by emulsion polymerization in the presence of a polymerization initiator which is soluble in organic solvents and has at least limited solubility in water, and in the further presence of a free non-polymerizable emulsifying acid, also soluble in organic solvents, and the conversion of such an emulsion polymer by spray drying into a polymer powder which is completely soluble in organic solvents to form clear solutions from which polymer films of reduced water sensitivity can be formed.
摘要:
A method for making an aqueous polymodal synthetic resin dispersion by the emulsion polymerization of an ethylenically unsaturated monomer difficultly soluble in water, or a mixture of such monomers forming a polymer which is water insoluble under the conditions of polymerization, in an aqueous phase containing an emulsifier and a water soluble polymerization initiator, which method comprises adding a seed latex to the polymerization mixture in the course of the emulsion polymerization before more than 40 weight percent of said monomers have been polymerized, the particles of said seed latex being smaller by a factor ranging from 2 to 15 than are particles already formed by emulsion polymerization, the amount by weight of the particles in the seed latex being not greater than 10 percent by weight of the monomers and the ratio by weight of particles of said seed latex to the weight of the monomers already polymerized being from 1:4 to 1:500.
摘要:
What is disclosed is making highly concentrated, bimodal, aqueous synthetic resin dispersions by the emulsion polymerization of ethylenically unsaturated monomers, in the presence of emulsifiers and free radical-forming initiators, by adding to a first latex containing a first dispersed synthetic resin and an aqueous phase, a second latex containing a second dispersed synthetic resin and an aqueous phase and a monomer phase containing a free-radically polymerizable monomer, and then polymerizing the monomer, the average size of the particles of said first resin differing by a factor between 2 and 15 from that of the particles of second resin, the total weight of the resins and monomers representing 100 parts by weight, and the total weight of the aqueous phases representing not more than 70 parts by weight.
摘要:
A bioactive PMMA (polymethylmethacrylate) bone cement contains a powder component and a reactive monomer liquid, wherein the powder component and the reactive monomer liquid when mixed with one another react with one another and form a polymer-based solid material. The powder component contains particulate polymer powder of polymethylmethacrylates; a radical starter; and anionic copolymer nanoparticles. The anionic copolymer nanoparticles are distributed in nano-particulate form within the particulate powder component or coated as a film on particles of the particulate polymer powder.