Aqueous polymer dispersions

Abstract

A method for producing an aqueous dispersion of at least two prepolymers, each prepolymer being at least partially modified by a graft addition polymer produced in a polymer solution, the method comprising the steps of: i) providing A solution of a first prepolymer consisting of a diepoxy resin and at least one other prepolymer than polyester in an organic carrier liquid, ii) combining the polymer-containing solution with an ethylenically unsaturated mixing monomers comprising an effective amount of a copolymerizable disperse moiety, iii) providing an effective amount of a graft polymerization initiator, iv) allowing or causing the monomers to polymerize and graft to at least some of the prepolymer to form a modified A solution of the polymer, v) optionally adding a crosslinking agent to the solution iv), vi) dispersing the solution of the modified polymer and the optional crosslinking agent in an aqueous medium to form a stable dispersion of particles.

Description

technical field

[0001]

[01] The present invention relates to a process for the production of aqueous polymer dispersions comprising prepolymers modified by graft addition polymers, in particular to bicyclic polymers modified by graft addition polymers Oxygen resin and polyvinyl butyral resin. Background technique

[0002]

[02] Metal food and beverage containers, often referred to as cans, are often coated on the inside surface to prevent a reaction between the contents and the metal from which the can is made. Such reactions lead to both detrimental can spoilage and potentially damaging effects on the contents, especially in terms of quality and taste changes. Without an inner coating, most food or beverage cans will not remain usable for long. The coating is typically applied to the flat metal by roll coating prior to can formation and then dried and / or cured in a baking operation. Typical oven temperatures used are about 200°C for 6 to 12 minutes. The can is then made ...