Preparation method of organic silicon modified normal-temperature multiple self-crosslinked epoxy resin emulsion

Abstract

The invention discloses a preparation method of organic silicon modified normal-temperature multiple self-crosslinked epoxy resin emulsion. The preparation method comprises the following steps: opening a ring of epoxy resin by using lauric acid; consuming away epoxy groups; performing grafting polymerization by using double-bond organo-siloxane, diacetone-acrylamide and an acrylic acid type monomer; and neutralizing the emulsion and adding hexane diacid dihydrazide to obtain the organic silicon modified normal-temperature multiple self-crosslinked epoxy resin emulsion. After the emulsion is formed into a film, ketone carbonyl and hydrazine have dehydration reaction under an acidic condition to generate a hydrazine compound; silanol and an active group of a polymer are condensed to form a three-dimensional network structure in order to realize normal-temperature multiple self-crosslinking. The solid content of the emulsion prepared by the method disclosed by the invention is 45% to 55%; the adhesive force reaches 0-1 grade after the film is formed by room temperature curing; the impact resistance is 50kg.cm to 65kg.cm; the flexibility is 2mm to 3mm; the water resistance is 120h to 150h; and the resistance to a 3% NaCl solution is 100h to 180h. The emulsion disclosed by the invention can be widely applied to various water-based paints as base resin.

Description

technical field [0001] The invention relates to an epoxy resin emulsion, in particular to a method for preparing an organosilicon-modified room temperature multiple self-crosslinking epoxy resin emulsion. Water-based architectural coatings and the like have a wide range of applications and belong to the field of functional polymer materials. Background technique [0002] Epoxy resins are widely used in the fields of coatings, adhesives and composite materials because of their good mechanical properties, adhesive properties, curing shrinkage and process properties. However, most epoxy resins are insoluble in water and easily soluble in organic solvents, which are flammable, explosive, and pollute the environment, which brings a lot of inconvenience to storage, transportation and construction. At this stage, domestic epoxy resins still need to add a large amount of co-solvents during the water-based process, and the solid content is basically below 40%, which is not really en...

AI Technical Summary

Problems solved by technology

[0004] The invention patent with the authorized notification number CN102432831B discloses a preparation method of a one-component normal temperature self-drying water-based epoxy resin modified by unsaturated fatty acid and its coating, although it can also realize normal temperature self-crosslinking and water-based epoxy resin It has good performance, but it does not first use lauric acid to open the ring of epoxy resin, consume epoxy groups, and then use acrylic monomers for grafting, so the reaction process is difficult to control, and gels are prone to occur. It is also difficult to increase the solid content of the obtained product

The publication number is CN103319665A. On the basis of the invention patent with the authorized announcement number CN102432831B, the cross-linking monomer glycidyl methacrylate and N-methylol acrylamide are added to realize multiple self-crosslinking. The reaction steps are complicated, but the performance is better than the former. It has been greatly improved, and this technology does not involve silicone modification. In terms of mechanical properties, especially in terms of impact resistance and flexibility, it needs to be further improved, which seriously affects its application performance.

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