Synthesis And Properties Of Dodecyldiethoxylamine Derivatives

In this paper, dodecyldiethoxylamine was synthesized by the reaction of dodecyl amine with ethylene oxide. Then the surfactants with hydroxyethyl groups were synthesized using dodecyldiethoxylamine. Some properties of these surfactants were studied. The effects of adding hydroxyethyl group on the properties of the surfactants have been analyzed. There are four main experimental studies in this dissertation.1. Synthesis of dodecyldiethoxylamine derivatives. Two kind of dodecyldiethoxylamine derivatives with hydroxyethyl groups, dodecyldiethoxylamine oxide (DDEAO), and dodecyl-di(2-hydroxyethyl)-methylammonium chloride (DHHAC) were synthesized. The structures were characterized by IR and1H-NMR spectroscopy. The results show that the products are the target compounds with high purity.2. Physicochemical performances of Dodecyldiethoxylamine Derivatives. The effects of pH, temperature and ionic strength on aggregation behaviors of DDEAO were investigated. The results were also compared with those of dodecydimethylamine oxide (DDMAO). The experimental results demonstrate that DDEAO shows good surface activity over a large pH range, especially under weakly acidic condition. Compared with DDMAO, the surface activity of DDEAO is somewhat superior to that of DDMAO. The physicochemical properties of quaternary ammonium type cationic surfactants, dodecyl-(2-hydroxyethyl)-dimethylammonium chloride (DHDAC), and DHHAC with hydroxyethyl groups were studied systematically and compared with that of dodecyltrimethylammonium chloride (DTAC). Results indicate that the surface activity increases with increasing the number of hydroxyethyl groups on hydrophilic groups of surfactants.3. Application properties of dodecyldiethoxylamine derivatives. Emulsifying capacity of DDEAO was investigated and compared with that of dodecyldimethylamine oxide (DDMAO). For its capacity of emulsifying liquid paraffin, DDEAO is found to be better than DDMAO, but it is the opposite for emulsifying soybean oil. The foaming properties and thickening function of DDEAO and DDMAO in mixtures with alcohol ether sulfate and alkylbenzene sulfonate were also studied. As expected, complex surfactant systems exhibit good foaming ability and two kind of amine oxide exhibit a good thickening function. The wetting abilities of two kind of amine oxide surfactants (DDEAO, DDMAO), AES, ethoxylated alcohols and mixtures of amine oxides with AES and AEOn were investigated. The effects of surfactant concentrations, surfactant types, numbers of ethylene oxide unit and temperatures on the wetting ability of mixed systems have been researched. DTAC, DHDAC and DHHAC as corrosion inhibitors for carbon steel in1M HCl solution were evaluated. In addition, the antistatic properties of fabric finished with DDMAO, DDEAO, DTAC, DHDAC and DHHAC as conditioners were also studied. The results show that those properties increase with increasing the number of hydroxyethyl groups on hydrophilic groups of surfactants.4. Synergism in mixtures of dodecyldiethoxylamine derivatives and other surfactants. The synergetic behaviors in the mixed systems of DDEAO/DTAC and DDEAO/SDS in aqueous solution were investigated through surface tension measurements. Stronger attractive interaction and greater synergism is exhibited in the mixed surfactants of the DDEAO/SDS than the DDEAO/DTAC mixed systems. The synergetic behaviors of surfactant mixtures of the anionic surfactant (AES) with quaternary ammonium type cationic surfactants (DTAC, DHDAC and DHHAC) were investigated. The detergency and foaming properties of mixed systems were also studied. The three mixed systems showed a synergistic effect in the JW-01and JW-02detergency tests, however, they showed poor detergency in the JW-03detergency tests. By comparing the three complex systems, the surface activity and foaming properties increased with an increase in the number of hydroxyethyl groups on the cationic surfactant component.