Process for the manufacture of aqueous copolymer dispersions and their use
AssigneeWacker Chemie AG
InventorsPeter Ball, Klaus Marquardt, Manfred Selig, Klaus Hafener
Life of this patent
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Abstract
Aqueous copolymer dispersions suitable for use in the manufacture of adhesives or as binding agents or as coating substances are produced by the emulsion polymerization of from 1 to 50% by weight of ethylene and from 99 to 50% by weight of vinyl monomers. With the process of the invention, in which, as vinyl monomers, vinyl chloride and, if desired, other ethylenically-unsaturated monomers, for example esters, are used, a higher ethylene content in the copolymer can be obtained at a lower pressure than hitherto. For this purpose, the greater part of the vinyl monomers is metered in and, in addition, an inert organic substance is used.
Claims25
In the process for the manufacture of fine-particle aqueous copolymer dispersions having a solids content of from 10% to 75% by weight, calculated on the dispersions, by means of the emulsion polymerization of
- (a) from 1% to 50% by weight of ethylene and
- (b) from 99% to 50% by weight of at least one vinyl monomer by means of radical initiators and in the presence of emulsifiers and/or protective colloids and, optionally further standard additives, the vinyl monomer phase comprising
- (b1) from 60% to 100% by weight of vinyl chloride (VC),
- (b2) from 0 to 40% by weight of oil-soluble mono-ethylenically-unsaturated monomers copolymerizable with ethylene and vinyl chloride, and
- (b3) from 0 to 10% by weight of monomers selected from the group consisting of mono-ethylenically-unsaturated monomers containing at least one functional group, multiple ethylenically-unsaturated monomers, and mixtures thereof, the improvement consisting essentially in that
- I the vinyl monomer phase (b) is present at the start in an amount of approximately 1% to 40% by weight, and
- II at least one inert organic substance having a water solubility of from 10.sup.-3 to 200 g/l and a molecular weight of not more than 1000, in an amount of from 0.1% to 15% by weight, calculated in each case on the total weight of component (b), is present at least partly at the start, the said organic substance being selected from the group consisting of (A) esters, partial esters and polyesters of monobasic and polybasic organic carboxylic acids of 1 to 20 carbon atoms and mono-and polyhydric alcohols of 1 to 20 carbon atoms optionally interrupted by up to 3 oxygen atoms and optionally substituted with epoxy, --OH, alkoxy of 1 to 8 carbon atoms and/or phenoxy, (B) esters of phosphoric acid with at least one member of the group of the group consisting of phenols and monohydric alcohols of 1 to 20 carbon atoms optionally interrupted with up to 3 oxygen atoms and both optionally substituted with alkoxy of 1 to 8 carbon atoms, phenoxy or chlorine, (C) ketones of 5 to 20 carbon atoms, (D) chlorohydrocarbons and fluorohydrocarbons of 1 to 20 carbon atoms with no carbon atoms substituted with more that two chlorines, (E) aromatic hydrocarbons of 6 to 20 carbon atoms, (F) esters of organic sulfonic acids of 4 to 20 carbon atoms with monohydric alcohols of 4 to 20 carbon atoms and mixtures thereof,
- III polymerization of the initial monomers phase is initiated by addition of at least one peroxide compound,
- IV the remainder of component (b) and optionally, of the inert organic substance, is metered in during polymerization over a period of at least 2 hours, and
- V polymerization is carried out at temperatures of from 0.degree. to 120.degree. C. under an ethylene pressure of from 10 to 150 bar, which is built up at the latest by the moment when the initial monomer phase has polymerized.
Dependencies are inferred from the claim text.