Preparation method of siloxane modified polyaspartic acid ester

Abstract

The invention discloses a preparation method of siloxane modified polyaspartic acid ester. The method comprises the step of adding primary amine in gamma-aminopropyl trialkoyl saline to a carbon-carbon double-bond in a maleate monomer to generate the siloxane modified polyaspartic acid ester. The method specifically comprises the following steps: dropwise adding maleate to the gamma-aminopropyl trialkoyl saline at 30-80 DEG C for 50-80 minutes; and then insulating and reacting for 12-24 hours at 60-100 DEG C to obtain the siloxane modified polyaspartic acid ester. The preparation method disclosed by the invention is free of side reactions, simple to operate and low in production cost, and the product has the advantages of being single in component, good in stability, low in viscosity, high in purity (the purity can reach over 99.5%) and the like. The prepared siloxane modified polyaspartic acid ester can be applied to any filed of gamma-aminopropyl trialkoyl saline, and particularly, the siloxane modified polyaspartic acid ester has a relatively remarkable application performance in polyurethane waterproof field.

Description

technical field [0001] The invention belongs to the field of synthesis of chemical products, and relates to a method for preparing a siloxane-modified polyaspartic acid ester through an organic chemical reaction of double bond addition, in particular to a maleate-modified γ-ammonia A method for preparing siloxane-modified polyaspartate from propyltrialkoxysilane. Background technique [0002] The silane coupling agent itself acts as a "molecular bridge" to form a firm and stable bond between two weakly bonded interfaces, which can obviously connect two substances with different properties. The mechanism of action of the silane coupling agent is that under certain conditions, small molecule alcohols (methanol, ethanol) are hydrolyzed to form silane polycondensed alkoxysilanes, which are mainly coupled with inorganic substrates, while the organic functional groups at one end of the silane coupling agent It has a certain compatibility with organic polymers, and the two can be ...

AI Technical Summary

Problems solved by technology

However, the silane coupling agents described in the above-mentioned patent documents all have highly active primary amino groups and short-chain alkyl groups, and the reaction speed with isocyanates in organic polymers is too fast, and the short-chain alkyl groups are compatible with the polymer substrate. Therefore, in the actual application process, there will be a reaction that will lead to poor compatibility and uniformity of the system, and the viscosity of the resin will rise rapidly, which will eventually affect the binding ability of the silane coupling agent and the organic polymer.

[0004] There is also a patent CN200610124089.8 that uses acrylate to modify γ-aminopropyltrialkoxysilane, but the double bond activity of acrylate is low and the double bond is less hindered, so the modified silane coupling agent has primary amines , secondary amines and tertiary amines, although they can effectively improve their compatibility with polymer substrates, but due to the high activity of primary amines, tertiary amines have a catalytic effect, so the modified γ-aminopropyltrialkoxy The reaction speed between silane and isocyanate in organic polymers is still fast, resulting in a rapid rise in resin viscosity after mixing, poor system compatibility and uniformity, and the binding ability of silane coupling agent and organic polymers is also unsatisfactory

Images