JPS5976883A - Corrosion inhibitor for metal - Google Patents

Abstract

PURPOSE:To obtain a novel superior corrosion inhibitor for metal by using a specified bisphenol type quat. ammonium compound as a principal component. CONSTITUTION:A novel bisphenol type quat. ammonium compound represented by the formula is synthesized. In the formula, X is a counter ion to quat. ammonium, Y is 1-6C alkylene, -O-, -S-, -SO- or -SO4-, each of R1-R4 is same or different to each other and H, 1-3C alkyl or hydroxyalkyl respectively, R5 is alkylene, hydroxyalkylene, hydroxyaralkylene, aminoalkylene, aminoaralkylene or alkylene or aralkylene having amido or ether bond, and R6 is halogen or alkyl bonded to each phenylene group by addition or substitution. The quat. ammonium compound is used as a principal component to obtain a corrosion inhibitor for metal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal corrosion inhibitor in water, an aqueous salt solution, an inorganic or 41-organic acid aqueous solution. More specifically, the present invention is based on metal! The present invention particularly relates to an agent useful as an active ingredient of a pickling corrosion inhibitor for steel.

Generally, when metals are rolled, plated, painted, etc.
Surface treatment is performed by pickling, but at that time, not only scale and rust are removed from the metal surface, but also the pickled surface is severely corroded by the acid. Therefore, when pickling metals, effective metal corrosion inhibitors are required to suppress metal loss, reduce TiY consumption, and improve the surface finish.

The properties that a metal corrosion inhibitor should have are: ■ Preventing wasteful consumption of acid, ■ Preventing wasteful dissolution of processed metals, and ■ Low foaming properties that do not cause trouble in the waste acid recovery process. be.

In general, aliphatic and aromatic amines, thimeureas, mercaptans, aldehydes, and heterocyclic compounds are used as metal Irfi catalytic inhibitors. Cationic surfactants consisting of two groups of lipophilic groups with low affinity have been used, but none of them satisfy all requirements (f) and do not have a sufficient suppressive effect.

The present inventors conducted intensive research to find a new compound with a stronger metal corrosion inhibiting effect, and as a result, they newly synthesized a bisphenol-type quaternary ammonium compound represented by the following general formula, and the present invention We have developed a metal corrosion inhibitor.

According to the present invention, there is provided a metal corrosion inhibitor whose main component is a bisphenol-type quaternary ammonium compound represented by the following general formula (1).

In the formula, X is C1, Br, HCOO, CH3COO, H
2PO4゜■(2P031H8o4.H2O2,cH3
so4. c2H5so41CII5-@-803,NO
, , No , etc. represents a counter ion of quaternary ammonium, Y is an alkylene group having 1 to 6 carbon atoms, or -〇-
, -8-1-8O-, -802-, R4゜R2
, R, and R4 are the same or different groups, and each represents an alkyl group having 1 to 3 hydrogen atoms or a hydroxyalkyl group, and R5 is alkylene, aralkylene, hydroxyalkylene, hydroxyalalkylene, Aminoalkylene, aminoalkylene, or alkylene or aralkylene containing an amide bond or ether bond! + R6 represents a halodane atom or an alkyl group added or attached to a phenylene group, p
is 0 or an integer from 1 to 4, and and m are each from 1 to
is an integer of 3, and n is an integer of 1 to 1o.

The compound of formula I according to the present invention can be synthesized in various ways, but it can mainly be carried out by the following method. First of all, bisphenol-derived conductors having halodane atoms at both ends, such as bisphenol A hydrin, bisphenol S dichlorohydrin,
Thiobisphenol nochlorohydrin, tetrabromobisphenol S dichlorohydrin, etc., and amine compounds having tertiary amines at both ends, such as tetramethylethylenediamine, tetramethylethylenediamine, N.

This is a method of synthesis by quaternizing N, N', N'-tetraethyl-N and hydroxyethylnoethylenetriamine, etc., by a known method.

The second method uses bisphenol visiting conductors having epoxy groups at both ends, such as bisphenol A nobrisidyl ether, bisphenol S diglycidyl ether, thiobisphenol zoglycidyl ether, and tetrabromobisphenol S diglycidyl ether. This is a method of synthesis by a known reaction between the above-described amino compound and an inorganic acid salt of an amino compound having tertiary amines at both ends.

In the compound of general formula I according to the present invention, if n is 1() or more, the solubility of the product in water or acid will decrease, which is not preferable. Desirably, R7>f5 or less.

Since the compound of the present invention is a bisphenol-type polycation, it can achieve an excellent metal corrosion inhibiting effect with an extremely small amount compared to low-molecular-weight cationic compounds, has low foaming properties, is easy to work with, and is easy to remove. It has the characteristic of maintaining excellent performance even when used at high temperatures for long periods of time.

The invention will be explained below with examples. In the examples, "part" and "chi" indicate parts by weight and i, respectively.

Production Example 1 435 parts of bisphenol S dichlorohydrin and 116 parts of tetramethylethylenediamine were placed in a reaction H vessel, 250 parts of isoprolyl was added and dissolved in W (after heating,
The reaction was carried out at 80°C for 2 hours.

The product was a pale yellow soft solid with a reaction rate of 98% determined from the chlorine ion concentration, with an average molecular weight of about 2200 (n is about 4).

Production Examples 2 to 6' Synthesized in the same manner as in JJA Example 1 to obtain the respective products as shown in Table 1.

Production Example 7 340 parts of bisphenol A diglycidyl ether and tetramethylglobyrenzoamine (7) phosphorus M! 326 parts were put into a reactor, 200 parts of methanol was added thereto to dissolve it, and the mixture was heated and reacted at 60° C. for 3 hours. The product was a pale yellow solid with an average molecular weight of about 2000 (n is about 3).

Production example 8 It was synthesized in the same manner as in Production Example 7.

The composition of each product obtained in the above production examples is shown in Table 1.
It is as follows.

Below is the blank space 1 item 11.
The effect of the metal corrosion inhibitor of the present invention on corrosion of 0x50x2.3) was determined.

Acid liquid II? 1. ．． : Two pieces of mild steel and I\iei? !
300 mA Immersion temperature and time: 50°C, 2 hours Corrosion inhibitor added acid: 30 ppm Judgment method: Table 2 shows the results of measuring the weight loss rate (A).

Red 2 *15 low molecular weight Katimene compounds were used in the comparative example.

Performance test example 2 The effectiveness of the corrosion inhibitor of the present invention was measured under the following conditions.

11th Erosion Tip: 10% Shiohama - 1-8% Ferrous ions (added as ferrous chloride) Acid solution %: 300ml of acid solution for 2 mild steel slabs Immersion conditions: 9
0'C, 20 minutes Judgment method: The results of measuring the stagnation rate @) are shown in Table 3 ◇ and 3 Performance test example 3 Polished mild steel plate in tap water (JIS G-3141-
The effect of the corrosion inhibitor of the present invention on the corrosion of 8PCCB 80X20X1) was measured.

Corrosion conditions: A test was performed under stirring in tap water at 50° C. for 100 hours. Evaluation method: The results of measuring the corrosion inhibition rate (a) are shown in Table 4.

Table 4 *A low molecular weight cationic compound was used in the ratio example.

As mentioned above, the product of the present invention has a significant corrosion inhibiting effect.

11￥g’Fllll applicant NICCA CHEMICAL INDUSTRY CO., LTD. patent application agent Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Tsuyoshi Yoshida Patent attorney Akira Yamaguchi

Claims (1)

[Claims] (1) In the gold dust formula whose main component is a bisphenol-type quaternary ammonium compound represented by the following general formula I, X represents a counter ion of quaternary ammonium, and Y represents a carbon number of 1. ~
6 alkylene group, or -01-s-1-so- or -502-, R,, R2, R. and R/j: the same or mutually different groups, each representing a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a hydroxyalkyl group, R5 is alkylene, aralkylene, hydroxyalkylene, hydroxyalalkylene,
Aminoalkylene, aminoalkylene:/, or alkylene or aralkylene containing an amide bond or ether bond, R6 represents a halokene atom or an alkyl group added to or directly replaced with a phenylene group, p is O or 1 is an integer from ~4, and and m are each from 1 to 3
is an integer of 1-10, and n is an integer of 1-10.