An anti-rust agent for the hot-rolled steel structure cavity of rail transit, its preparation method and application

Abstract

The present invention discloses an antirust agent for the cavity of hot-rolled steel structures in rail transit, its preparation method and application. It is prepared from 1 part of butyl octanoic acid-doped polyaniline, 10-12 parts of dodecyl hexadecanol erucate and 6-7 parts of base oil by weight ratio. The present invention aims at the cavity structure of the corroded hot-rolled steel structure, solves the problem that physical or chemical methods cannot be used for rust removal, adsorbs the corroded part through strong penetration, wrapping and shielding effects, prevents further corrosion, and at the same time penetrates to the surface of the base material to achieve a long-term and stable anti-corrosion effect.

Description

Technical Field

[0001] The present invention relates to the field of rust preventives, and particularly to a rust preventive for the cavity of hot-rolled steel structures in the rail transit industry. Background Art

[0002] The frame structure of rail transit vehicles is generally made of hot-rolled square steel, and the carriage "skeleton" is formed by welding. The hot-rolled steel itself has an oxide layer, and no special protection is carried out during the turnover process. Before painting, surface sandblasting is carried out to remove surface rust. However, effective rust removal treatment cannot be achieved for the internal space of the hot-rolled square steel. Therefore, for this cavity structure, special rust prevention treatment is required. In the traditional automotive industry, cavity rust preventive wax is usually used for anti-corrosion, but the cavity rust preventive wax mainly acts on the cavity gap and the surface of electrophoretic paint ED, which belongs to a compensatory rust prevention measure. For the already rusted surface, effective penetration, wrapping and shielding cannot be carried out. Therefore, the cavity rust preventive wax used in the traditional automotive industry cannot form an effective protection measure in the cavity of hot-rolled square steel in the rail transit industry. Moreover, the traditional rust preventive grease has a short rust prevention period and cannot meet the long-term anti-corrosion needs of rail transit. Moreover, the above are all petrochemical resources, which is not conducive to the effective utilization of resources. Summary of the Invention

[0003] In order to solve the above-mentioned existing technical problems, the present invention provides a rust preventive for the cavity of hot-rolled steel structures in rail transit, which can effectively penetrate, wrap and shield rust components, and is green, low-carbon and environmentally friendly.

[0004] The technical solution adopted by the present invention is: a rust preventive for the cavity of hot-rolled steel structures in rail transit, which is made of butyl octanoic acid-doped polyaniline, dodecyl hexadecanol erucate and base oil.

[0005] Further, the rust preventive for the cavity of hot-rolled steel structures in rail transit is made of 1 part of butyl octanoic acid-doped polyaniline, 10-12 parts of dodecyl hexadecanol erucate and 6-7 parts of base oil according to the weight ratio.

[0006] Further, the preparation method of the butyl octanoic acid-doped polyaniline (gerbate acid-doped polyaniline) includes the following steps: adding polyaniline powder to deionized water, ultrasonic dispersing for 10 min, then dropping concentrated hydrochloric acid, continuing to stir for 2 h for the first doping, then dropping ammonia water, continuing to stir for 2 h for de-doping, fully washing with water, adding butyl octanoic acid (dodecyl gerbate) for the second doping, dispersing and dissolving into an emulsion state, heating to 90 °C, vacuum dehydrating, and reacting for 12 h to obtain butyl octanoic acid-doped polyaniline.

[0007] Further, by mass ratio, polyaniline: deionized water: concentrated hydrochloric acid: ammonia water: butyl octanoate = (8 - 12):(40 - 60):(0.2 - 0.4):(0.4 - 0.6):(5 - 7).

[0008] Further, the preparation method of the dodecyl hexadecanol erucate (Guerbet alcohol erucate) includes the following steps: Take an appropriate amount of erucic acid and heat it to 70°C, add dodecyl hexadecanol (octacosanol Guerbet alcohol), stir and disperse for 5 - 10 min. After mixing evenly, heat it to 110°C, react for 2 h, then dehydrate under vacuum, dropwise add concentrated hydrochloric acid, stir and react for 4 - 6 h under nitrogen protection, cool to room temperature, wash with water, and dry to obtain dodecyl hexadecanol erucate.

[0009] Further, by mass ratio, erucic acid: dodecyl hexadecanol: concentrated hydrochloric acid = (80 - 90):(60 - 70):1.

[0010] Further, the base oil is isoparaffinic solvent oil.

[0011] Further, the isoparaffinic solvent oil is C16 isoparaffinic solvent oil.

[0012] A preparation method of a rust inhibitor for the cavity of hot-rolled steel structures in rail transit includes the following steps: Add dodecyl hexadecanol erucate and base oil into a reaction kettle, heat to 80°C, stir and disperse for 60 min, then add butyl octanoate-doped polyaniline, and disperse at high speed for 30 min to obtain a rust inhibitor for the cavity of hot-rolled steel structures in rail transit.

[0013] The application of the rust inhibitor provided by the present invention in the cavity of hot-rolled steel structures in rail transit.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1. The rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention contains Guerbet alcohol erucate doped with polyaniline in its structure. Its main anti-corrosion performance comes from the synthesized Guerbet alcohol erucate and Guerbet acid-doped polyaniline with a similar structure. Among them, Guerbet alcohol erucate has good adsorption, penetration, and encapsulation properties, which play a role in sealing the rust products on the hot-rolled plate. Guerbet acid-doped polyaniline has a passivation effect and plays a shielding role on the substrate of the hot-rolled plate. Traditional fossil resource petroleum products mainly play a preventive role on the metal surface, but have limited rust prevention effect on the rusted surface. Through the strong penetration of the erucic acid and Guerbet alcohol structure, Guerbet alcohol erucate can well coat the rust products and directly penetrate to the substrate surface, cooperate with the passivation effect of polyaniline, and form a good anti-corrosion effect for hot-rolled steel.

[0016] 2. Since it is difficult for traditional intrinsic polyaniline and polyaniline doped with ordinary proton acids to disperse in general dispersion media (oil phase and water phase), the rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention uses Guerbet acid (butyl octanoic acid) to secondarily dope polyaniline, and then disperses it at a high speed with Guerbet alcohol erucate at a certain temperature. Under the action of a similar structure, good dispersion of polyaniline is achieved.

[0017] 3. The rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention contains polyaniline doped with butyl octanoic acid and has a passivation and isolation shielding function.

[0018] 4. The rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention uses Guerbet-based erucate, which has excellent penetration due to the Guerbet alcohol and erucic acid structures and the synergistic effect of isoparaffin. The surface tension of the rust inhibitor of the present invention is ≤20 dyn / cm, which can penetrate through the rusty product to act on the substrate surface and wrap the rusty product to block further rusting.

[0019] 5. The rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention is different from traditional petroleum resource rust inhibitors and eliminates the consumption of fossil energy. The erucic acid used in the present invention has many characteristics such as green, wide source, easy preparation, light color, and low odor. The present invention uses the bio-based green and environmentally friendly raw material erucic acid to carry out an esterification reaction with Guerbet alcohol, and uses Guerbet acid to dope polyaniline to play a passivation role on the substrate, which not only wraps the loose rust products but also penetrates into the substrate to form a passivation effect, forming a stable and effective rust inhibitor for harsh surfaces.

[0020] 6. To improve the dispersion stability problem of polyaniline in the medium, the rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention introduces butyl octanoic acid with a structure similar to Guerbet alcohol erucate for doping. After doping, the polyaniline and Guerbet alcohol erucate are dispersed at a high temperature. Due to the similar structure, they are more likely to adsorb each other. At the same time, the polyaniline doped with butyl octanoic acid adopts a secondary doping process and is more stable itself.

[0021] 7. The isoparaffin solvent oil used in the rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention can effectively help penetration during the anti-corrosion process and reduce the surface tension.

[0022] 8. The rust inhibitor for the cavity of hot-rolled steel structures in rail transit provided by the present invention is mainly applied to the rail transit industry and is used for the inner wall of the cavity of the car body frame with hot-rolled steel structures. Due to the Guerbet alcohol erucate structure, the rust inhibitor has excellent permeability and wrapping properties. The doped polyaniline with a similar structure has a passivation effect. The combined action of the two makes the present invention have a strong protective effect on the rusty surface and extremely strong resistance to salt spray medium corrosion, which can meet the operation requirements of the rail transit industry for ultra-long periods. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a mechanism diagram of the rust inhibitor for the hot-rolled steel structure cavity of rail transit provided by the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be described in detail below with reference to the embodiments.

[0025] Embodiment 1

[0026] (1) A rust inhibitor for the hot-rolled steel structure cavity of rail transit, and the preparation method includes the following steps:

[0027] 1. Preparation of butyl octanoic acid-doped polyaniline (guerbet acid-doped polyaniline):

[0028] Take 10 g of polyaniline powder and add it to 50 g of deionized water. After ultrasonic dispersion for 10 min, add 0.3 g of concentrated hydrochloric acid with a concentration of 37.5%. Continue stirring for 2 h. After the first doping, add 0.5 g of ammonia water with a concentration of 25%, continue stirring for 2 h for de-doping. After thorough washing with water, add 6 g of butyl octanoic acid (dodecyl guerbet acid, trade name ISOCARB 12) for secondary doping, disperse and dissolve into an emulsion state, heat up to 90 °C, dehydrate under vacuum, and react for 12 h to obtain butyl octanoic acid-doped polyaniline.

[0029] 2. Preparation of dodecyl hexadecyl erucate (guerbet alcohol erucate):

[0030] Take 80 g of erucic acid and heat it up to 70 °C. Add 60 g of dodecyl hexadecanol (octacosyl guerbet alcohol, trade name ISOFOL 28) and stir for 5 - 10 min. After mixing evenly, heat up to 110 °C, react for 2 h and then dehydrate under vacuum. Add 1 g of concentrated hydrochloric acid with a concentration of 37.5%, stir and react for 4 - 6 h under nitrogen protection, cool to room temperature, wash with water, and dry to obtain dodecyl hexadecyl erucate.

[0031] 3. Preparation of the rust inhibitor:

[0032] Add 60 g of dodecyl hexadecyl erucate and 30 g of carbon hexadecane isoparaffin solvent oil (trade name ISOPAR M) to the reaction kettle, heat up to 80 °C, stir and disperse for 60 min, then add 5 g of butyl octanoic acid-doped polyaniline, and disperse at high speed of 2000 rpm for 30 min to obtain a rust inhibitor for the hot-rolled steel structure cavity of rail transit. This rust inhibitor is a guerbet alcohol erucate containing doped polyaniline.

[0033] (2) Comparative Example 1

[0034] The difference is that the butyl octanoic acid-doped polyaniline is replaced by polyaniline.

[0035] 1. Preparation of dodecyl hexadecanol erucate (Guerbet alcohol erucate): same as (I)

[0036] 2. Preparation of rust inhibitor:

[0037] Add 60 g of dodecyl hexadecanol erucate and 30 g of C16 isoparaffin solvent oil (trade name ISOPAR M) into the reaction kettle, heat up to 80 °C, stir and disperse for 60 min, then add 5 g of polyaniline, and disperse at a high speed of 2000 rpm for 30 min to obtain the rust inhibitor.

[0038] (III) Comparative Example 2

[0039] The difference is that the doped polyaniline is polyaniline doped with hydrochloric acid, and no de-doping and secondary doping are carried out.

[0040] 1. Preparation of hydrochloric acid-doped polyaniline:

[0041] Take 10 g of polyaniline powder and add it to 50 g of deionized water. After ultrasonic dispersion for 10 min, dropwise add 0.3 g of concentrated hydrochloric acid with a concentration of 37.5%, continue stirring for 2 h for primary doping, wash with water, dehydrate under vacuum, and dry to obtain hydrochloric acid-doped polyaniline.

[0042] 2. Preparation of dodecyl hexadecanol erucate (Guerbet alcohol erucate): same as (I)

[0043] 3. Preparation of rust inhibitor:

[0044] Add 60 g of dodecyl hexadecanol erucate and 30 g of C16 isoparaffin solvent oil (trade name ISOPAR M) into the reaction kettle, heat up to 80 °C, stir and disperse for 60 min, then add 5 g of hydrochloric acid-doped polyaniline, and disperse at a high speed of 2000 rpm for 30 min to obtain the rust inhibitor.

[0045] (IV) Comparative Example 3

[0046] The difference is that there is no dodecyl hexadecanol erucate, and calcium petroleum sulfonate is used.

[0047] 1. Preparation of butyl octanoic acid-doped polyaniline (Guerbet acid-doped polyaniline): same as (I)

[0048] 2. Preparation of rust inhibitor:

[0049] Add 60 g of calcium petroleum sulfonate and 30 g of C16 isoparaffin solvent oil (trade name ISOPAR M) into the reaction kettle, heat up to 80 °C, stir and disperse for 60 min, then add 5 g of butyl octanoic acid-doped polyaniline, and disperse at a high speed of 2000 rpm for 30 min to obtain the rust inhibitor.

[0050] (V) Technical indicators

[0051] The rust inhibitors prepared in the present invention and Comparative Examples 1-3 were tested according to the test method and the rated thickness, and the results are shown in Table 1.

[0052] Table 1

[0053]

[0054] As can be seen from Table 1, through the data of the above examples and comparative examples, it is proved that butyl octanoic acid-doped polyaniline (gerbert acid-doped polyaniline) as a secondary doping process has better stability and dispersion than polyaniline and primary-doped protonic acid polyaniline in the present invention, and is more conducive to penetration and anti-corrosion. At the same time, dodecyl hexadecyl erucate is more suitable as an anti-rust and penetrant in the system of the present invention than petroleum sulfonate rust inhibitors, which can greatly improve the anti-rust performance of hot-rolled plates and reduce the surface tension. Because of its similar gerbert structure to butyl octanoic acid-doped polyaniline, it plays a role in synergistically dispersing the powder.

Claims

1. An antirust agent for the cavity of hot-rolled steel structures in rail transit, characterized in that, the antirust agent for the cavity of hot-rolled steel structures in rail transit, by weight ratio, comprises 1 part of butyl octanoic acid-doped polyaniline, 10 - 12 parts of dodecyl hexadecanol erucate, and 6 - 7 parts of base oil; The preparation method of the butyl octanoic acid-doped polyaniline comprises the following steps: Take polyaniline powder and add it to deionized water. After ultrasonic dispersion for 10 min, add concentrated hydrochloric acid, and continue stirring for 2 h. After primary doping, add ammonia water, and continue stirring for 2 h for de-doping. After thorough washing with water, add butyl octanoic acid for secondary doping, disperse and dissolve into an emulsion state, heat up to 90 °C, dehydrate under vacuum, and react for 12 h to obtain butyl octanoic acid-doped polyaniline.

2. The antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 1, characterized in that, by mass ratio, polyaniline: deionized water: concentrated hydrochloric acid: ammonia water: butyl octanoic acid = (8 - 12): (40 - 60): (0.2 - 0.4): (0.4 - 0.6): (5 - 7).

3. The antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 1, characterized in that, The preparation method of the dodecyl hexadecanol erucate comprises the following steps: Take an appropriate amount of erucic acid and heat it up to 70 °C, add dodecyl hexadecanol, stir and disperse for 5 - 10 min. After mixing evenly, heat up to 110 °C, react for 2 h, then dehydrate under vacuum, add concentrated hydrochloric acid, stir and react for 4 - 6 h under nitrogen protection, cool to room temperature, wash with water, and dry to obtain dodecyl hexadecanol erucate.

4. The antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 3, characterized in that, by mass ratio, erucic acid: dodecyl hexadecanol: concentrated hydrochloric acid = (80 - 90): (60 - 70):

1.

5. The antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 1, characterized in that, the base oil is isoparaffinic solvent oil.

6. The antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 5, characterized in that, the isoparaffinic solvent oil is C16 isoparaffinic solvent oil.

7. The preparation method of the antirust agent for the cavity of hot-rolled steel structures in rail transit according to claim 1, characterized in that, The preparation method comprises the following steps: Add dodecyl hexadecanol erucate and base oil to a reaction kettle, heat up to 80 °C, stir and disperse for 60 min, then add butyl octanoic acid-doped polyaniline, and disperse at high speed for 30 min to obtain the antirust agent for the cavity of hot-rolled steel structures in rail transit.

8. The application of the antirust agent according to claim 1 in the cavity of hot-rolled steel structures in rail transit.

Images