阅读说明：本技术 一种防锈铝合金无铬钝化剂及其制备方法 (Antirust aluminum alloy chromium-free passivator and preparation method thereof ) 是由 张广勋 沈勇 王超 王清芳 于 2020-08-01 设计创作，主要内容包括：本发明提供一种防锈铝合金无铬钝化剂及其制备方法,涉及铝合金钝化技术领域,包括下述重量份的原料：草酸、植酸、磷酸、硝酸、硅溶胶、硅烷偶联剂、水溶性硅树脂、成膜助剂和水。包括如下步骤：A、按重量称取原料加入水中搅拌均匀；B、将硅溶胶、硅烷偶联剂、成膜助剂等加入到步骤A的混合液中搅拌；C、除去杂质后,得到防锈铝合金无铬钝化剂。本发明中硅溶胶属胶体溶液、无臭、无毒,不影响被覆盖物的本色,通过成膜助剂的设置,能够与原料进行复配后得到复合型铝合金钝化剂,能在铝合金表面形成具有网状结构的致密的薄膜,本发明不含任何有毒有害物质对人体及环境无害,可以循环使用,钝化效果较好,具有良好的的经济效益和社会效益。(The invention provides an antirust aluminum alloy chromium-free passivator and a preparation method thereof, which relate to the technical field of aluminum alloy passivation and comprise the following raw materials in parts by weight: oxalic acid, phytic acid, phosphoric acid, nitric acid, silica sol, a silane coupling agent, water-soluble silicon resin, a film-forming assistant and water. The method comprises the following steps: A. weighing the raw materials according to the weight, adding the raw materials into water, and uniformly stirring; B. adding silica sol, a silane coupling agent, a film-forming additive and the like into the mixed solution obtained in the step A and stirring; C. after impurities are removed, the antirust aluminum alloy chromium-free passivator is obtained. The silica sol belongs to a colloidal solution, is odorless and nontoxic, does not affect the natural color of a covered object, can be compounded with raw materials through the arrangement of the film-forming assistant to obtain the composite aluminum alloy passivator, can form a compact film with a net-shaped structure on the surface of the aluminum alloy, does not contain any toxic and harmful substances, is harmless to human bodies and the environment, can be recycled, has a good passivation effect, and has good economic and social benefits.)

1. The rust-proof aluminum alloy chromium-free passivator is characterized by comprising the following raw materials in parts by weight:

3-8 parts of oxalic acid, 8-12 parts of phytic acid, 3-8 parts of phosphoric acid, 3-8 parts of nitric acid, 3-8 parts of silica sol, 2-3 parts of a silane coupling agent, 20-30 parts of water-soluble silicone resin, 40-50 parts of a film-forming assistant and 100-200 parts of water.

2. The chromium-free passivator for rust-inhibiting aluminum alloy according to claim 1, characterized in that: the water-soluble silicon resin is methyl phenyl hydrogen-containing silicon resin.

3. The rust-proof aluminum alloy chromium-free passivator and the preparation method thereof according to claim 1, wherein: the concentration of the nitric acid is 65-70%.

4. The chromium-free passivator for rust-inhibiting aluminum alloy according to claim 1, characterized in that: the film-forming assistant is prepared from the following raw materials in parts by weight: 50-80 parts of ethyl phenyl polyethylene glycol, 10-15 parts of bisphenol A epoxy resin, 0.5-1 part of glyceryl monostearate, 100-120 parts of ethylene glycol butyl ether, 100-120 parts of dipropylene glycol butyl ether, 80-100 parts of propylene glycol propyl ether, 50-100 parts of trimethylolpropane trimeric propylene glycol ether and 4-6 parts of acrylic acid.

5. The chromium-free passivator for rust-inhibiting aluminum alloy according to claim 1, characterized in that: the concentration of the water-soluble silicone resin is 30-100 g/L.

6. The chromium-free passivator for rust-inhibiting aluminum alloy according to claim 1, characterized in that: the preparation method of the film-forming aid comprises the following steps:

firstly, adding ethyl phenyl polyethylene glycol, bisphenol A epoxy resin and glyceryl monostearate into a reaction container, and stirring for 2-2.5 hours;

secondly, adding ethylene glycol butyl ether, dipropylene glycol butyl ether, propylene glycol propyl ether and trimethylolpropane trimeric propylene glycol ether into the reaction vessel in the first step, and stirring until the materials are molten;

and thirdly, adding acrylic acid into the reaction container in the second step, stirring, reacting for 2-3 hours, and then adjusting the pH value to 6-7 to obtain the required film-forming aid.

7. The preparation method of the rust-proof aluminum alloy chromium-free passivator according to claim 1, characterized by comprising the following steps:

A. weighing the raw materials according to the weight, adding oxalic acid, phytic acid, phosphoric acid and nitric acid into water, and uniformly stirring to prepare a mixed solution;

B. adding silica sol, a silane coupling agent, water-soluble silicone resin and a film-forming additive into the mixed solution obtained in the step A, stirring for 0.5-1 h, cooling, and adjusting the pH value to 4-5;

C. and D, filtering the mixture obtained in the step B by using a filter screen, and removing impurities to obtain the antirust aluminum alloy chromium-free passivator.

8. The chromium-free passivator for rust-inhibiting aluminum alloy according to claim 6, wherein: the temperature of the reaction vessel in the first step is 80-100 ℃, and the temperature of the reaction vessel in the second step is 130-150 ℃.

Technical Field

The invention relates to the technical field of aluminum alloy passivation, in particular to an antirust aluminum alloy chromium-free passivator and a preparation method thereof.

Background

The aluminum alloy has many excellent properties, and is widely applied to a plurality of fields of transportation, packaging containers, aerospace, household appliances, mechanical manufacturing, building profiles, electronic communication and the like. However, the aluminum alloy has poor properties such as corrosion resistance, wear resistance, hardness and the like, and is easily corroded during use, so the aluminum profile needs to be subjected to effective surface treatment before coating to avoid or reduce corrosion.

Chromate passivation treatment, which is the most common aluminum alloy surface treatment technology, has the advantages of convenience in use, low price, good corrosion resistance and decorative performance, but hexavalent chromium in a treatment solution has high toxicity and serious environmental pollution, and is limited or prohibited by multi-country policy and regulations. Therefore, it is necessary to find a chromium-free passivation system.

Disclosure of Invention

The invention aims to provide a rust-proof aluminum alloy chromium-free passivator and a preparation method thereof, so as to solve the technical problems.

In order to solve the technical problems, the invention adopts the following technical scheme: the rust-proof aluminum alloy chromium-free passivator and the preparation method thereof comprise the following raw materials in parts by weight:

3-8 parts of oxalic acid, 8-12 parts of phytic acid, 3-8 parts of phosphoric acid, 3-8 parts of nitric acid, 3-8 parts of silica sol, 2-3 parts of a silane coupling agent, 20-30 parts of water-soluble silicone resin, 40-50 parts of a film-forming assistant and 100-200 parts of water.

Preferably, the water-soluble silicone resin is methylphenyl hydrogen-containing silicone resin.

Preferably, the concentration of the nitric acid is 65-70%.

Preferably, the film-forming aid is prepared from the following raw materials in parts by weight: 50-80 parts of ethyl phenyl polyethylene glycol, 10-15 parts of bisphenol A epoxy resin, 0.5-1 part of glyceryl monostearate, 100-120 parts of ethylene glycol butyl ether, 100-120 parts of dipropylene glycol butyl ether, 80-100 parts of propylene glycol propyl ether, 50-100 parts of trimethylolpropane trimeric propylene glycol ether and 4-6 parts of acrylic acid.

Preferably, the concentration of the water-soluble silicone resin is 30-100 g/L.

The rust-proof aluminum alloy chromium-free passivator is characterized by comprising the following components in parts by weight: the preparation method of the film-forming aid comprises the following steps:

firstly, adding ethyl phenyl polyethylene glycol, bisphenol A epoxy resin and glyceryl monostearate into a reaction container, and stirring for 2-2.5 hours;

secondly, adding ethylene glycol butyl ether, dipropylene glycol butyl ether, propylene glycol propyl ether and trimethylolpropane trimeric propylene glycol ether into the reaction vessel in the first step, and stirring until the materials are molten;

and thirdly, adding acrylic acid into the reaction container in the second step, stirring, reacting for 2-3 hours, and then adjusting the pH value to 6-7 to obtain the required film-forming aid.

The rust-proof aluminum alloy chromium-free passivator and the preparation method thereof are characterized by comprising the following steps:

A. weighing the raw materials according to the weight, adding oxalic acid, phytic acid, phosphoric acid and nitric acid into water, and uniformly stirring to prepare a mixed solution;

B. adding silica sol, a silane coupling agent, water-soluble silicone resin and a film-forming additive into the mixed solution obtained in the step A, stirring for 0.5-1 h, cooling, and adjusting the pH value to 4-5;

C. and D, filtering the mixture obtained in the step B by using a filter screen, and removing impurities to obtain the antirust aluminum alloy chromium-free passivator.

Preferably, the temperature of the reaction vessel in the first step is 80-100 ℃, and the temperature of the reaction vessel in the second step is 130-150 ℃.

The invention has the beneficial effects that:

the silica sol belongs to a colloidal solution, is odorless and nontoxic, has a relatively large specific surface area, is colorless and transparent, does not affect the natural color of a covered object, has very good dispersibility and permeability when being mixed with other substances, can be compounded with raw materials through the arrangement of a film-forming assistant to obtain the composite aluminum alloy passivator, can form a compact film with a net structure on the surface of the aluminum alloy, effectively prevents the aluminum alloy from being oxidized and rusted, and has a remarkable protection effect on the aluminum alloy.

Detailed Description

The present invention will be further described with reference to specific embodiments for the purpose of facilitating an understanding of technical means, characteristics of creation, objectives and functions realized by the present invention, but the following embodiments are only preferred embodiments of the present invention, and are not intended to be exhaustive. Based on the embodiments in the implementation, other embodiments obtained by those skilled in the art without any creative efforts belong to the protection scope of the present invention.

Specific embodiments of the present invention are described below.