Synthesis of Amphoteric Polymer Surfactants by Grafting Long-Chain Quaternary Ammonium Salts with Carboxymethyl Cellulose

Carboxymethyl cellulose grafted long-chain quaternary ammonium salt to synthesize amphiphilic polymer surfactant Jiang Gangqi Zhou Zhifeng (School of Chemistry and Chemical Engineering, Central South University of Technology, Changsha, 083) Grafted by carboxymethyl cellulose (CMC) to dimethyl tetradecyl Synthesis of water-soluble amphoteric cellulose derivatives (M EQCM C) from long-chain quaternary ammonium salts prepared from amines and epichlorohydrin, and determination of suitable conditions for quaternization of CMC: isopropyl alcohol: water = 4:1 (volume ratio) The solvent was used. The reaction temperature was 65°C and the reaction time was 5 h. The structure of M EQCM C was characterized by X-ray diffraction, DT A, elemental analysis and infrared spectra.

Amphoteric polymer surfactants have many unique properties, and their research and development are increasingly valued. By grafting a long chain quaternary ammonium salt on the anionic polymer carboxymethyl cellulose (CMC), a class of natural polymeric amphoteric surfactants can be obtained. Such amphoteric cellulose derivatives not only display under certain conditions The thickening, dispersion, solubilization, film formation and other properties, but also has the advantages of biodegradation, safe use, rich source of raw materials, in foreign countries, amphoteric polymer surfactants have been widely used in oil extraction, paint, construction , pharmaceuticals, and environmental protection agencies use tetradecylamine and epichlorohydrin as raw materials to synthesize long carbon chain quaternary ammonium glycidoxypropyl dimethyl tetradecyl ammonium chloride (M EQ), followed by carboxymethyl Cellulose (CMC) was grafted and amphoteric polymer surfactant (M EQCM C) was synthesized.

1 Experiment 1.1 drug and instrument CM C (Whatman imported subpackage), the degree of carboxymethyl substitution is 0.44, the average molecular weight is 5. 2×104, impregnation, purification of tetradecylamine before use, chemically pure, Tokyo Chemicals imports the rest of the reagents are analytical grade.

Infrared spectrometer, Siemens D500 X-ray diffractometer, thermal analysis TAS100, ZD 2 type potentiometer.

1. Preparation of 2 dimethyl tetradecylamine 25 mL of ethanol was placed in a four-neck flask and tetradecylamine 15 was added to stir it to melt. Transfer to a constant temperature water bath, and add 18 to 20 mL of formic acid at about 55°C. 2 g. In minutes, the temperature was raised to the stratification, the upper liquid was distilled under reduced pressure to remove ethanol to give a pale yellow liquid dimethyltetradecylamine 15.6 g.

1. Preparation of 3 glycidyldimethyltetradecylammonium chloride (MEQ) Dimethyltetradecylamine 12 g (0.05 mol) was placed in a four-necked flask and 60 mL of solvent was added. The temperature was raised to 55°C, and 5.5 g (0.06 mol) of epichlorohydrin was slowly added dropwise. The solution was refluxed for several hours. The residual epichlorohydrin and the solvent were distilled off under reduced pressure to obtain a pale yellow paste M EQ with potential. Titration was measured for its yield.

1. 4 CMC Quaternization reaction in a four-necked flask, adding 50 mL of solvent, 5.5 g, holding for a few hours at a certain temperature, cooling, acetone precipitation, neutralization with acetic acid to neutrality, washing with 90 ethanol, 60 °C Vacuum dried carboxymethyl cellulose quaternary ammonium salt 2 Results and discussion 2.1 Influence of MEQ synthesis factors Solvents, reaction time on M EQ yield.

In the preparation of quaternary ammonium salts, polar alcohols or water may be used as a solvent in order to disperse the charge. With alcohol as the solvent, the tertiary amine and epichlorohydrin of the reactants have good solubility in alcohol, but the viscosity of the product is relatively large, and water is used as a solvent for the subsequent reaction. The viscosity of the product is small, but the reactants are in water. The solubility is small, reducing the chance of contact between reactants. Experiments show that the solvent is preferably isopropanol:water=2:1 (by volume) aqueous alcohol solution. The reaction time is based on the research of Fine Chemicals, and 4 papers have been published.

Fine petrochemicals are appropriate.

No. solvent/m L reaction time/h yield, 60 mL of isopropanol Note: tetradecylamine, epichlorohydrin are all 0.05 mol, and the reaction temperature is 55°C.

2. 2 Main factors influencing the quaternization of CMC The influence of reaction temperature, time and medium composition on the grafting efficiency of M EQ.

No. Temperature/°C Time/h Reaction Medium/m L RE=The amount of grafted M EQ/M EQ loading can be seen from Table 2. CM C quaternization temperature is preferably 65°C. Excessive temperature can cause side reactions. Increasing the reaction time to 6 h is better when the isopropanol aqueous solution is used as the medium than the ethanol aqueous solution. This is better than the isopropyl alcohol to destroy the crystallization ability than the ethanol. The isopropanol:water ratio is 4:1 (volume ratio).

2.3 Spectrum analysis The following analysis was performed for the M EQCM C with the number 19 and the raw material CM C.

2.3.1 Thin-layer Chromatographic Analysis To check the degree of tetramethylammonium methylation, a comparative thin-layer analysis of tetradecylamine and dimethyltetradecylamine was performed. The solvent was n-butanol:acetic acid:acetone:petroleum ether. = 3:1:1:1 (volume ratio), development time is 55-60 min. The results are shown in Figure 1.

Methyl tetradecylamine, with good parallelism for each lot, qualitatively indicates that methylation is more complete.

According to the literature, the decomposition temperature of CM C is 546°C, there are two phase transition temperatures at 275°C and 362°C, 362°C is the three phase transition temperature of the carboxymethyl shedding temperature, and the final decomposition temperature is 591°C, indicating M Due to the interaction of zwitterions, EQCM C significantly improves the temperature resistance.

The 2.3.3X diffraction pattern has strong diffraction at 2θ of 10° and 22°, but has basically become disordered. This is because the hydrogen bonds in the crystal plane are destroyed after the long chain quaternary ammonium salt is introduced into the CMC. The crystal structure of CM C is damaged.

Fine Petrochemicals 2000 2 3. 4 Elemental Analysis M EQ CM C and CM C elemental analysis is shown in Table 3.

Samples can be seen from Table 3, M EQCM C increased N, Cl elements, and the content of C, H elements increased significantly due to the introduction of long chain quaternary ammonium salt.

The infrared spectra of CM C and M EQ CM C are shown in Figure 4.

There is stretching vibration and the stretching vibration of M EQCM C occurs at 158, indicating that the carboxyl group exists in the form of negative ion salt and the carboxylate salt has no stretching vibration absorption, and the stretching vibration band ratio at 3464 cm is significantly wider. This is due to the introduction of new OH in quaternization.

3 Conclusions Using tetradecylamine as raw material, the tertiary amine was synthesized by the primary amine formate formaldehyde method, and then reacted with epichlorohydrin in isopropanol solution at a volume fraction of 3/4 for 5 h at 55°C. The quaternization agent glycidyldimethyltetradecylammonium (M EQ) was prepared. The optimal reaction conditions for the grafting of CM C and M EQ were as follows: temperature 65 °C, time 6 h, reaction medium composition. Isopropyl alcohol: water = 4:1 (volume ratio), the highest grafting efficiency of M EQ can be obtained. This type of amphoteric polymer surfactant is safe for use, biodegradable, and rich in raw material sources. It is expected to be used in daily chemicals and pharmaceuticals. , environmental protection, oil field mining has a good application prospects.

2 Institute of Science and Technology, Ministry of Chemical Industry. Chemical Products Handbook (Organic Chemical Materials). Beijing: Hua Li, Huang Chengya, Yang Zhili. Polymer Materials Science and Engineering, 1998, 14( 5):