CN108299212B - Cyclohexene ester based gemini cationic surfactant and preparation method thereof - Google Patents

Abstract

The invention discloses a cyclohexene-ester-based gemini cationic surfactant and a preparation method thereof, wherein the cyclohexene-ester-based gemini cationic surfactant is obtained by reacting 4-cyclohexenyl-1, 2-dicarboxylic acid di (dimethylaminoethyl) ester with bromohexadecane. The surfactant disclosed by the invention has good surface activity, emulsifying property and low-temperature adaptability, and shows good corrosion inhibition and protection properties in the aspect of carbon steel acid corrosion protection.

Description

A kind of cyclohexenyl ester-based gemini cationic surfactant and preparation method thereof

technical field

The invention relates to a cyclohexenyl ester-based gemini cationic surfactant and a preparation method thereof, belonging to the field of fine chemicals.

Background technique

The long-term use of surfactants has brought a great impact on the environment. The carbon-carbon chemical bonds in the molecule are difficult to degrade, and the benzene ring has special stability (such as sodium alkyl benzene sulfonate), which is particularly difficult to degrade. However, surfactants with longer hydrophobic carbon chains (such as 16 and 18 carbons) generally have a higher Krafft point and have poor solubility at low temperatures, which affects their use.

Another way to reduce the environmental impact of surfactants is to develop surfactants with higher surface activity. Gemini surfactants, compared with traditional surfactants, have become a hot research topic in the field of surfactants because they often exhibit excellent properties due to their unique structures.

Molecules contain weak chemical bonds, such as ester bonds, which are easily degraded in nature. Ester-based surfactants have become an important variety of environmentally friendly surfactants, and the preparation of environmentally friendly surfactants has received extensive attention in the industry.

references:

[1] Wang Zhengwu, Li Ganzuo, Zhang Xiaoyi, et al. Research progress on degradation of surfactants [J]. Daily Chemical Industry, 2001, 31(5): 32-36.

[2] Chen Fengsheng, Liu Xuemin, Hu Zengrong, et al. Study on the synthesis and properties of amide group-containing divalent cationic surfactants [J]. Daily Chemical Industry, 2008, 38(5): 285-288.

[3] Yu Pengming, Zhang Wei, Wang Fengshou, et al. Research progress of cationic Gemini surfactants [J]. Printing and Dyeing Auxiliaries, 2015, 32(9): 6-12.

[4] Yang Jianzhou, Lin Li, Fu Zhigang, et al. Research on biodegradable cationic ester surfactants [J]. Daily Chemical Industry, 2005, 35(1): 9-11.

SUMMARY OF THE INVENTION

In order to solve the problems that surfactants are difficult to degrade in the environment and the long-chain alkyl surfactants have a high Kraff point and are limited in use temperature, the present invention aims to provide a cyclohexenyl ester-based gemini cationic surfactant and a preparation method thereof. The molecular structure of the cyclohexenyl ester-based gemini cationic surfactant of the present invention contains an ester group, which can improve the degradation performance of the surfactant in the environment. The Krafft point of the surfactant is lower than 0°C, and has good surface activity, emulsification performance, temperature adaptability, in addition to showing good corrosion inhibition performance of carbon steel corrosion.

The cyclohexenyl ester-based gemini cationic surfactant of the present invention, its structural formula is:

The preparation method of the cyclohexenyl ester-based gemini cationic surfactant of the present invention comprises the following steps: dissolving 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester in an organic solvent, adding bromotenyl Hexane is stirred and reacted at a certain temperature. After the reaction is completed, crystallize by cooling, filter, and dry to obtain the target product. The solvent is recovered by distillation and can be recycled.

Among them, the molar ratio of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester to bromohexadecane is 1:(2-4), preferably 1:3.

The reaction can be carried out at room temperature to the reflux temperature of the solvent, preferably at the reflux temperature; the reaction time is 24-72 h, preferably 36-48 h.

The organic solvent is a polar solvent, selected from one or a mixture of methanol, ethanol, isopropanol, acetonitrile, acetone, butanone, etc., preferably ethanol, acetone or acetonitrile.

The preparation process of the present invention is as follows:

The raw material 4-cyclohexenyl-1,2-dicarboxylate bis(dimethylaminoethyl) ester used in the present invention can be dimethyl 4-cyclohexenyl-1,2-dicarboxylate and dimethyl Aminoethanol is obtained by transesterification in the presence of a catalyst, and other conventional preparation methods can also be used.

The surfactant of the invention has good surface activity, emulsifying performance and low temperature adaptability, and exhibits good corrosion inhibition protection performance in the aspect of acid corrosion protection of carbon steel.

Description of drawings

Fig. 1 is the infrared spectrum of cyclohexenyl ester-based gemini cationic surfactant.

Figure 2 is a hydrogen nuclear magnetic resonance image of the cyclohexenyl ester-based gemini cationic surfactant.

Figure 3 is a mass spectrum of a cyclohexenyl ester-based gemini cationic surfactant.

Detailed ways

In order to further understand the present invention, the preferred embodiments of the present invention are described below with reference to specific examples. However, it should be understood that this description is only for further illustrating the features and advantages of the present invention, rather than limiting the rights of the present invention.

Example 1:

To 0.5mol of dimethyl 4-cyclohexenyl-1,2-dicarboxylate, 1.5mol of dimethylaminoethanol and 1.5g of 30% sodium methoxide were added, and the reaction was stirred at 120°C for 12h, and the resulting methanol and excess were removed under reduced pressure. dimethylaminoethanol, cooled, neutralized by adding 1 g of glacial acetic acid, dissolved in 50 g of water, extracted with ethyl acetate (150 g × 2), combined with the organic phases, dried over anhydrous magnesium sulfate, filtered, and distilled to remove the solvent to obtain 4 -cyclohexenyl-1,2-dicarboxylate bis(dimethylaminoethyl) ester 0.36mol, yield 72%.

Example 2:

Add 50 mL of acetone and 0.3 mol of bromohexadecane to 0.1 mol of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester, stir and reflux for 36 h, crystallize by cooling, filter, wash, After drying, 0.052 mol of the target product was obtained, and the yield was 52%.

Example 3:

Add 50 mL of acetonitrile and 0.3 mol of bromohexadecane to 0.1 mol of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester, stir and reflux for 48 h, crystallize by cooling, filter, wash, After drying, 0.058mol of the target product was obtained, and the yield was 58%.

Example 4:

Add 50 mL of acetone and 0.25 mol of bromohexadecane to 0.1 mol of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester, stir at 40°C for 72 h, crystallize by cooling, filter and wash , After drying, 0.053 mol of the target product was obtained, and the yield was 53%.

Example 5:

To 0.1 mol of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester, 30 mL of isopropanol and 0.3 mol of bromohexadecane were added, and the reaction was stirred at 40°C for 72 h, crystallized by cooling, and filtered. , washing and drying to obtain 0.049mol of the target product with a yield of 49%.

Example 6:

Add 50 mL of acetone recovered by distillation and 0.3 mol of bromohexadecane to 0.1 mol of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester, stir and reflux for 36 h, crystallize by cooling, filter , washing and drying to obtain 0.052mol of the target product with a yield of 52%.

Example 7:

The Krafft point of the cyclohexenyl ester-based gemini cationic surfactant was measured by the cloud point method, and the Krafft point was less than 0 °C. The CMC value of the cyclohexenyl ester-based ^gemini cationic surfactant was measured by the conductometric method. mol/L, and the γ _CMC value of the cyclohexenyl ester-based gemini cationic surfactant was measured by the drop volume method to be 37.57 mN/m.

Example 8:

Test its emulsifying performance according to the following method: Pipette for testing respectively pipette 40mL, 1.0×10 ^-3 m/L cyclohexenyl ester-based gemini cationic surfactant solution into a 100mL graduated cylinder with stopper, and then pipette 40mL Put cyclohexane into the same stoppered measuring cylinder, close the lid, vibrate violently up and down five times, let stand for 1 min, vibrate five times again, let stand for 1 min, and repeat five times. Then time with a stopwatch, and record the emulsification time as 519s when 10 mL of the water phase is separated.

Example 9:

The corrosion inhibition efficiency of carbon steel was tested according to the following method: at 30 °C, in a 1.0 mol/L HCl solution, the concentration of cyclohexenyl ester-based gemini cationic surfactant was 1×10 ^-5 mol/L, and the measured The corrosion inhibition efficiency (η _W ) was 91.53%. The corrosion inhibition efficiency (η _W ) is calculated as follows:

分别是不含和含有缓蚀剂时，碳钢片的失重值。where W _corr and

are the weight loss values of carbon steel sheets without and with corrosion inhibitor, respectively.

The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, the present invention can also be carried out in several ways. Improvements and modifications also fall within the scope of protection of the claims of the present invention.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. a kind of cyclohexenyl ester base double cationic surfactant, is characterized in that its structural formula is:

2. a preparation method of the cyclohexenyl ester-based double cationic surfactant according to claim 1, is characterized in that: be 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl ) ester is dissolved in the organic solvent, adding bromohexadecane, stirring the reaction at a certain temperature, after the reaction is finished, crystallizing by cooling, filtering, and drying to obtain the target product; The molar ratio of 4-cyclohexenyl-1,2-dicarboxylic acid bis(dimethylaminoethyl) ester to bromohexadecane is 1:(2～4); The reaction is carried out at reflux temperature; the reaction time is 36-48h. 3. preparation method according to claim 2, is characterized in that: The molar ratio of 4-cyclohexenyl-1,2-dicarboxylate bis(dimethylaminoethyl) ester to bromohexadecane was 1:3. 4. preparation method according to claim 2, is characterized in that: The organic solvent is one or a mixture of methanol, ethanol, isopropanol, acetonitrile, acetone and butanone. 5. preparation method according to claim 4, is characterized in that: The organic solvent is ethanol, acetone or acetonitrile.

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