阅读说明：本技术 一种防腐蚀性能较好的水性聚氨酯涂料制备方法 (Preparation method of waterborne polyurethane coating with good corrosion resistance ) 是由 王保军 拾振洪 李海洋 金传亮 回留柱 王家振 于 2019-11-21 设计创作，主要内容包括：本发明公开了一种防腐蚀性能较好的水性聚氨酯涂料制备方法,具体涉及防腐涂料技术领域,制备的水性聚氨酯涂料具有优越的耐腐蚀性能,并且,其耐酸耐碱性较好,抗划伤,附着力强,且硬度高；将氧化石墨烯与3,5-二氨基-1,2,4-三氮唑在高温下球磨处理,一方面3,5-二氨基-1,2,4-三氮唑中的氨基可以与氧化石墨烯片层上的环氧基团发生反应,从而利用其环状共轭与氧化石墨烯之间形成一个大共轭体系,有利于电子的流动,增强其导电性能,另一方面,3,5-二氨基-1,2,4-三氮唑提供了活性较强的氨基和三氮唑,三氮唑中的氮原子可以与后续加入的钴离子、钛酸钙中氧原子络合,从而向氧化石墨烯表面引入较多金属离子,在高聚物基体中形成导电网络,从而提升所得涂料的防腐性能。(The invention discloses a preparation method of a waterborne polyurethane coating with good corrosion resistance, and particularly relates to the technical field of anticorrosive coatings, wherein the prepared waterborne polyurethane coating has excellent corrosion resistance, good acid and alkali resistance, scratch resistance, strong adhesive force and high hardness; the preparation method comprises the steps of carrying out ball milling treatment on graphene oxide and 3, 5-diamino-1, 2, 4-triazole at high temperature, wherein on one hand, amino in the 3, 5-diamino-1, 2, 4-triazole can react with epoxy groups on a graphene oxide sheet layer, so that a large conjugated system is formed between cyclic conjugation of the amino and the graphene oxide, the flow of electrons is facilitated, and the electric conductivity of the electrons is enhanced, on the other hand, the amino and the triazole with high activity are provided by the 3, 5-diamino-1, 2, 4-triazole, nitrogen atoms in the triazole can be complexed with cobalt ions and oxygen atoms in calcium titanate which are added subsequently, so that more metal ions are introduced to the surface of the graphene oxide, a conductive network is formed in a high polymer matrix, and the corrosion resistance of the obtained coating is improved.)

1. The preparation method of the waterborne polyurethane coating with good corrosion resistance is characterized by comprising the following steps:

(1) dispersing 10-12 parts by weight of graphene oxide in deionized water, dispersing for 15-20min at 35-40 ℃ and 150r/min under 130-15, adding 4-6 parts of cobalt chloride and 10-15 parts of calcium titanate, continuously dispersing for 10-14min, transferring the obtained system into a reaction kettle, reacting for 12-14h at 163 ℃ under 160-3 ℃, then cooling to room temperature at the rate of 2-3 ℃/min, filtering, washing with deionized water, and drying at 45-50 ℃ to obtain a graphene oxide compound containing metal ions;

(2) adding 50-80 parts of 1, 5-naphthalene diisocyanate into 180 parts of 120-organic acetone, stirring and dissolving at 40-45 ℃ and at 180rpm under 150-organic stirring for 15-20min, then adding 15-18 parts of the graphene oxide compound containing the metal ions obtained in the step (1), heating to 65-70 ℃, and reacting at 300rpm under 200-organic stirring for 4-5h to obtain a graphene oxide compound-isocyanate prepolymer containing the metal ions;

(3) and (3) adding 50-60 parts of polyol, 0.02-0.05 part of catalyst and 5-8 parts of chain extender into 50-80 parts of the prepolymer obtained in the step (2), continuously stirring for reaction for 3-5h, cooling, adding 2-3 parts of 1, 3-cyclohexyldimethylamine and 80-120 parts of ice water, and emulsifying at 1800rpm for 1-2h to obtain the catalyst.

2. The preparation method of the waterborne polyurethane coating with good corrosion resistance according to claim 1, wherein the graphene oxide obtained in the step (1) is subjected to the following treatment before use: adding 10-12 parts of graphene oxide, 5-7 parts of 3, 5-diamino-1, 2, 4-triazole and 20-25 parts of acetone into a ball milling tank, adding agate milling beads, carrying out ball milling for 2-3h at the rotation speed of a high-speed dispersion machine of 800-1000r/min and the oil bath temperature of 70-80 ℃, filtering the obtained product, washing with deionized water, and drying at 40-43 ℃.

3. The preparation method of the waterborne polyurethane coating with good corrosion resistance according to claim 1, wherein the calcium titanate obtained in the step (2) is pretreated by the following steps: the calcium titanate is roasted for 2 to 3 hours at the temperature of 120-125 ℃, and then is put into ice water for ball milling until the particle size is 100-500 mu m.

4. The method for preparing the waterborne polyurethane coating with better corrosion resistance according to claim 1, wherein the polyol in the step (3) is one of polypropylene oxide polyol or polysiloxane polyol.

5. The preparation method of the waterborne polyurethane coating with good corrosion resistance according to claim 1, wherein the catalyst in the step (3) is an organic bismuth catalyst DY-20, and the chain extender is one of 1, 4-butanediol or ethylene glycol.

Technical Field

The invention belongs to the technical field of anticorrosive coatings, and particularly relates to a preparation method of a waterborne polyurethane coating with good anticorrosive performance.

Background

The anticorrosive paint is a paint which is widely applied in modern industries, transportation, energy, ocean engineering and other departments, at present, the anticorrosive paint in the world is a synthetic paint mainly based on artificial synthetic resin, most of the synthetic paints contain a large amount of organic solvents, pigments with certain toxicity and the like, so that the environment is polluted and the health of people is harmed, and therefore, the water-based anticorrosive paint is the key point for researching and developing environment-friendly paints with the advantages of safe, convenient, energy-saving, environment-friendly and the like.

The aqueous polyurethane coating is a coating which takes aqueous polyurethane resin as a base material and water as a dispersion medium, has the advantages of no toxicity, no odor, no pollution, difficult combustion, low cost, difficult damage to the coated surface, easy construction, easy cleaning and the like, and also has the excellent performances of high hardness, wear resistance and the like inherent in the solvent type polyurethane coating. The patent with the application number of CN104789100B discloses a moisture-proof and corrosion-resistant waterborne polyurethane coating and a preparation method thereof, and the moisture-proof and corrosion-resistant waterborne polyurethane coating is prepared by polymerizing diphenylmethane diisocyanate and oligomer dihydric alcohol serving as main raw materials, trimethylolpropane serving as an auxiliary agent, an epoxy resin-diethanolamine adduct serving as an internal crosslinking agent and epoxy resin serving as a modifier.

Disclosure of Invention

Aiming at the problems, the invention aims to provide a preparation method of a water-based polyurethane coating with better corrosion resistance. .

The invention is realized by the following technical scheme:

(1) adding 10-12 parts of graphene oxide, 5-7 parts of 3, 5-diamino-1, 2, 4-triazole and 20-25 parts of acetone into a ball milling tank, adding agate milling beads, carrying out ball milling for 2-3h at the rotation speed of a high-speed dispersion machine of 800-1000r/min and the oil bath temperature of 70-80 ℃, filtering the obtained product, washing with deionized water, and drying at 40-43 ℃.

(2) The calcium titanate is roasted for 2 to 3 hours at the temperature of 120-125 ℃, and then is put into ice water for ball milling until the particle size is 100-500 mu m.

(3) Dispersing the obtained graphene oxide in deionized water, adding 4-6 parts of cobalt chloride and 10-15 parts of calcium titanate after dispersing for 15-20min at 35-40 ℃ and 150r/min, continuing dispersing for 10-14min, transferring the obtained system into a reaction kettle, reacting for 12-14h at 160-163 ℃ and then cooling to room temperature at the rate of 2-3 ℃/min, filtering, washing with deionized water, and drying at 45-50 ℃ to obtain a graphene oxide compound containing metal ions;

(4) adding 50-80 parts of 1, 5-naphthalene diisocyanate into 180 parts of 120-180 parts of acetone, stirring and dissolving for 15-20min at 40-45 ℃ and at 150-180rpm, then adding the obtained graphene oxide compound containing the metal ions, heating to 65-70 ℃, and reacting for 4-5h at 200-300rpm to obtain a graphene oxide compound-isocyanate prepolymer containing the metal ions;

(5) adding 50-60 parts of polyol, 0.02-0.05 part of catalyst and 5-8 parts of chain extender into 50-80 parts of prepolymer, continuously stirring for reaction for 3-5h, cooling, adding 2-3 parts of 1, 3-cyclohexyldimethylamine and 80-120 parts of ice water, and emulsifying at 1800rpm for 1-2h to obtain the product. The polyol is one of polypropylene oxide polyol or polysiloxane polyol, the catalyst is an organic bismuth catalyst DY-20, and the chain extender is one of 1, 4-butanediol or ethylene glycol.

The invention has the beneficial effects that: the waterborne polyurethane coating prepared by the invention has excellent corrosion resistance, good acid and alkali resistance, scratch resistance, strong adhesive force and high hardness, realizes the unification of long-acting corrosion resistance and environmental protection, and is suitable for field construction; firstly, carrying out ball milling treatment on graphene oxide and 3, 5-diamino-1, 2, 4-triazole at high temperature, wherein on one hand, amino in the 3, 5-diamino-1, 2, 4-triazole can react with epoxy groups on a graphene oxide sheet layer, so that a large conjugated system is formed between cyclic conjugation of the amino and the graphene oxide, the large conjugated system is favorable for electron flow and enhances the electric conductivity of the electrons, on the other hand, the 3, 5-diamino-1, 2, 4-triazole provides amino with strong activity and triazole, nitrogen atoms in the triazole can be complexed with cobalt ions and oxygen atoms in calcium titanate which are added subsequently, so that more metal ions are introduced to the surface of the graphene oxide, the electric conductivity of the obtained compound is further enhanced, and a network is formed in a high polymer matrix more easily, thereby improving the corrosion resistance of the obtained coating; and then, 1, 5-naphthalene diisocyanate and the graphene oxide compound containing metal ions are subjected to prepolymerization reaction through hydroxyl and amino, the graphene oxide compound containing metal ions and a high polymer substrate form network crosslinking, the mechanical property of the obtained coating is improved, and the rigidity and the high symmetry of the 1, 5-naphthalene diisocyanate improve the hardness of the coating and further enhance the corrosion resistance of the coating.

Detailed Description

The invention is illustrated by the following specific examples, which are not intended to be limiting.