A metal surface rust preventive and a method for preparing the same

Abstract

This invention discloses a metal surface rust inhibitor, comprising the following raw materials by mass percentage: deionized water: 80%–90%; organic polyol amine corrosion inhibitor: 6%–16%; heterocyclic high-efficiency corrosion inhibitor: 0.5%–3%; water-based film-forming agent: 2%–7%; nonionic low-foaming surfactant: 0.2%–1.5%; pH adjuster: 0.3%–1.5%; defoamer: 0.05%–0.3%. This invention is completely non-toxic and environmentally friendly, free of nitrites, chromium, nickel, phosphorus, and heavy metals, meeting environmental emission standards. It has a low odor, is easy to clean, non-greasy, and does not affect coating, phosphating, or assembly. It provides long-lasting rust prevention, forms a dense film with strong adhesion, significantly extends the rust prevention period, and is suitable for multiple metals, exhibiting no corrosion to carbon steel, cast iron, galvanized steel, and stainless steel. It has excellent rust prevention performance, is easy to apply, and can be applied by immersion, spraying, or brushing at room temperature, with fast drying.

Description

Technical Field

[0001] This invention relates to the field of metal surface technology, and more specifically to a metal surface rust inhibitor and its preparation method. Background Technology

[0002] Metal products are susceptible to corrosion and rusting from air, moisture, hand sweat, and acidic / alkaline gases during processing, transportation, and storage, leading to decreased precision, poor appearance, and increased scrap rates. However, existing rust inhibitors have the following shortcomings: 1. Oil-based rust inhibitors: high viscosity, heavy oil staining, difficult to clean, high cost, and impact on subsequent processes; 2. Traditional water-based rust inhibitors: contain toxic substances such as nitrites, chromium salts, and phosphates, which are carcinogenic, pollute the environment, and are difficult to treat; 3. Poor film-forming properties: thin film layer, easy to peel off, short rust prevention period, only suitable for short-term inter-process rust prevention; 4. Poor versatility: only suitable for ferrous metals, easily corroded or poorly rust-preventing for galvanized, stainless steel, and cast iron; 5. Weak resistance to salt spray and damp heat, unable to meet long-term storage requirements. Therefore, to avoid the shortcomings of existing technologies, it is necessary to improve them. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings and deficiencies of the prior art and provide an environmentally friendly, non-toxic, water-based, easy-to-clean, dense film-forming, long-lasting, stable, and multi-metal applicable metal surface rust inhibitor.

[0004] Another object of the present invention is to provide a method for preparing a rust inhibitor for metal surfaces.

[0005] This invention is achieved through the following technical solution:

[0006] A metal surface rust inhibitor, comprising the following raw materials by weight percentage:

[0007] Deionized water: 80%–90%;

[0008] Organic polyol amine corrosion inhibitors: 6%–16%;

[0009] Heterocyclic high-efficiency corrosion inhibitor: 0.5%–3%;

[0010] Aqueous film-forming agents: 2%–7%;

[0011] Nonionic low-foaming surfactant: 0.2%–1.5%;

[0012] pH adjuster: 0.3%–1.5%;

[0013] Defoamer: 0.05%~0.3%.

[0014] Furthermore, the organic polyol amine corrosion inhibitor is one or a combination of two of triethanolamine and monoethanolamine.

[0015] Furthermore, the heterocyclic corrosion inhibitor is one or a combination of two of benzotriazole and methylbenzotriazole.

[0016] Furthermore, the aqueous film-forming agent is one of an aqueous acrylic film-forming agent or a polyethylene glycol film-forming agent.

[0017] Furthermore, the nonionic surfactant is an isomeric alcohol polyoxyethylene ether.

[0018] Furthermore, the pH value of the metal surface rust inhibitor is 8.5–10.

[0019] A method for preparing a rust inhibitor for metal surfaces, characterized by comprising the following steps:

[0020] Step (1): Add deionized water at room temperature and stir;

[0021] Step (2): Add organic polyol amine corrosion inhibitor to dissolve;

[0022] Step (3): Add heterocyclic corrosion inhibitor and stir until homogeneous;

[0023] Step (4): Add aqueous film-forming agent and nonionic low-foaming surfactant;

[0024] Step (5): Add pH adjuster to adjust the pH value to 8.5-10;

[0025] Step (6): Add defoamer and filter out the material.

[0026] Compared with existing technologies, the metal surface rust inhibitor prepared by mixing organic polyol amine corrosion inhibitor, heterocyclic high-efficiency corrosion inhibitor, aqueous film-forming agent and nonionic low-foaming surfactant has the following beneficial effects:

[0027] 1. Completely non-toxic and environmentally friendly: Free of nitrites, chromium, nickel, phosphorus, and heavy metals, meeting environmental emission standards;

[0028] 2. Water-based system: low odor, easy to clean, non-greasy, and does not affect coating, phosphating, or assembly;

[0029] 3. Long-lasting rust prevention: The film is dense and has strong adhesion, significantly extending the rust prevention period;

[0030] 4. Versatile for multiple metals: It does not corrode carbon steel, cast iron, galvanized sheet, or stainless steel, and has excellent rust prevention.

[0031] 5. Easy to apply: can be applied by soaking, spraying, or brushing at room temperature, and dries quickly. Detailed Implementation

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] A metal surface rust inhibitor, characterized in that it comprises the following raw materials by weight percentage:

[0034] Deionized water: 80%–90%;

[0035] Organic polyol amine corrosion inhibitors: 6%–16%;

[0036] Heterocyclic high-efficiency corrosion inhibitor: 0.5%–3%;

[0037] Aqueous film-forming agents: 2%–7%;

[0038] Nonionic low-foaming surfactant: 0.2%–1.5%;

[0039] pH adjuster: 0.3%–1.5%;

[0040] Defoamer: 0.05%~0.3%.

[0041] Organic polyol amine corrosion inhibitors are one or a combination of two of triethanolamine and monoethanolamine.

[0042] Heterocyclic corrosion inhibitors are one or a combination of two of benzotriazole and methylbenzotriazole.

[0043] The aqueous film-forming agent is one of the aqueous acrylic film-forming agents and the polyethylene glycol film-forming agents.

[0044] The nonionic surfactant is isomeric alcohol polyoxyethylene ether.

[0045] The pH value of rust inhibitors for metal surfaces is 8.5–10.

[0046] A method for preparing a rust inhibitor for metal surfaces, characterized by comprising the following steps:

[0047] Step (1): Add deionized water at room temperature and stir;

[0048] Step (2): Add organic polyol amine corrosion inhibitor to dissolve;

[0049] Step (3): Add heterocyclic corrosion inhibitor and stir until homogeneous;

[0050] Step (4): Add aqueous film-forming agent and nonionic low-foaming surfactant;

[0051] Step (5): Add pH adjuster to adjust the pH value to 8.5-10;

[0052] Step (6): Add defoamer and filter out the material.

[0053] Example 1

[0054] Deionized water: 87.2%;

[0055] Triethanolamine: 10%;

[0056] Benzotriazole: 1%;

[0057] Water-based acrylic film-forming agent: 1%;

[0058] Isomeric alcohol polyoxyethylene ether: 0.5%;

[0059] pH adjuster: 0.7%;

[0060] Defoamer: 0.1%;

[0061] Add deionized water to the reactor at room temperature and start stirring (300 rpm to 500 rpm); add triethanolamine and stir until completely dissolved; add benzotriazole and continue stirring for 15 to 25 minutes until uniformly dissolved; add water-based acrylic film-forming agent and stir for 20 to 30 minutes; add isomeric alcohol polyoxyethylene ether and stir until transparent and homogeneous; add pH adjuster and adjust the pH value to 8.5 to 10; add defoamer and stir for 10 to 15 minutes, then filter and discharge.

[0062] Performance testing:

[0063] pH value: 9;

[0064] Appearance: Pale yellow transparent liquid;

[0065] Salt spray test: >72h;

[0066] Inter-process rust prevention: 30 to 45 days;

[0067] Applications: General long-term storage of carbon steel, cast iron, and galvanized parts.

[0068] Example 2

[0069] Deionized water: 83.5%;

[0070] Triethanolamine + Monoethanolamine: 12%;

[0071] Methylbenzotriazole: 1.5%;

[0072] Polyethylene glycol film-forming agent: 2%;

[0073] Isomeric alcohol polyoxyethylene ether: 0.6%;

[0074] pH adjuster: 0.8%;

[0075] Defoamer: 0.1%;

[0076] Add deionized water to the reactor at room temperature and start stirring (300 rpm to 500 rpm); add triethanolamine and monoethanolamine and stir until completely dissolved; add methylbenzotriazole and continue stirring for 15 min to 25 min until uniformly dissolved; add polyethylene glycol film-forming agent and stir for 20 min to 30 min; add isomeric alcohol polyoxyethylene ether and stir until transparent and homogeneous; add pH adjuster and adjust the pH value to 8.5 to 10; add defoamer and stir for 10 min to 15 min, then filter and discharge.

[0077] Performance testing:

[0078] pH value: 8.8;

[0079] Appearance: Pale yellow transparent liquid;

[0080] Salt spray: >120h;

[0081] Sealing and rust prevention: The film forms evenly and has excellent resistance to damp heat after more than 6 months;

[0082] Suitable for: ultra-strong sealing of carbon steel, cast iron, and galvanized parts.

[0083] Example 3

[0084] Deionized water: 89.45%;

[0085] Triethanolamine: 8%;

[0086] Benzotriazole: 0.8%;

[0087] Water-based acrylic film-forming agent: 1.2%;

[0088] Isomeric alcohol polyoxyethylene ether: 0.3%;

[0089] pH adjuster: 0.6%;

[0090] Defoamer: 0.15%;

[0091] Add deionized water to the reactor at room temperature and start stirring (300 rpm to 500 rpm); add triethanolamine and stir until completely dissolved; add benzotriazole and continue stirring for 15 to 25 minutes until uniformly dissolved; add water-based acrylic film-forming agent and stir for 20 to 30 minutes; add isomeric alcohol polyoxyethylene ether and stir until transparent and homogeneous; add pH adjuster and adjust the pH value to 8.5 to 10; add defoamer and stir for 10 to 15 minutes, then filter and discharge.

[0092] Performance testing:

[0093] pH value: 9.2;

[0094] Appearance: Pale yellow transparent liquid;

[0095] Salt spray test: >60h;

[0096] Inter-process rust prevention: 15 to 20 days;

[0097] Suitable for: mass production line sealing of carbon steel, cast iron, and galvanized parts; low cost and fast drying.

[0098] The present invention provides a metal surface rust inhibitor prepared by mixing an organic polyol amine corrosion inhibitor, a heterocyclic high-efficiency corrosion inhibitor, an aqueous film-forming agent, and a nonionic low-foaming surfactant. This rust inhibitor has the following beneficial effects:

[0099] 1. Completely non-toxic and environmentally friendly: Free of nitrites, chromium, nickel, phosphorus, and heavy metals, meeting environmental emission standards;

[0100] 2. Water-based system: low odor, easy to clean, non-greasy, and does not affect coating, phosphating, or assembly;

[0101] 3. Long-lasting rust prevention: The film is dense and has strong adhesion, significantly extending the rust prevention period;

[0102] 4. Versatile for multiple metals: It does not corrode carbon steel, cast iron, galvanized sheet, or stainless steel, and has excellent rust prevention.

[0103] 5. Easy to apply: can be applied by soaking, spraying, or brushing at room temperature, and dries quickly.

[0104] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rust inhibitor for metal surfaces, characterized in that: The following raw materials are included by weight percentage: Deionized water: 80%–90%; Organic polyol amine corrosion inhibitors: 6%–16%; Heterocyclic high-efficiency corrosion inhibitor: 0.5%–3%; Aqueous film-forming agents: 2%–7%; Nonionic low-foaming surfactant: 0.2%–1.5%; pH adjuster: 0.3%–1.5%; Defoamer: 0.05%~0.3%.

2. The metal surface rust inhibitor according to claim 1, characterized in that: The organic polyol amine corrosion inhibitor is one or a combination of two of triethanolamine and monoethanolamine.

3. The metal surface rust inhibitor according to claim 1, characterized in that: The heterocyclic corrosion inhibitor is one or a combination of two of benzotriazole and methylbenzotriazole.

4. The metal surface rust inhibitor according to claim 1, characterized in that: The aqueous film-forming agent is one of aqueous acrylic film-forming agents and polyethylene glycol film-forming agents.

5. The metal surface rust inhibitor according to claim 1, characterized in that: The nonionic surfactant is an isomeric alcohol polyoxyethylene ether.

6. The metal surface rust inhibitor according to claim 1, characterized in that: The pH value of the metal surface rust inhibitor is 8.5-10.

7. A method for preparing a rust inhibitor for metal surfaces, characterized in that: Includes the following steps, Step (1): Add deionized water at room temperature and stir; Step (2): Add organic polyol amine corrosion inhibitor to dissolve; Step (3): Add heterocyclic corrosion inhibitor and stir until homogeneous; Step (4): Add aqueous film-forming agent and nonionic low-foaming surfactant; Step (5): Add pH adjuster to adjust the pH value to 8.5-10; Step (6): Add defoamer and filter out the material.