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Double epoxy group double quaternary ammonium salts (DEpDQAS) were synthesized by epichlorohydrin (ECH) reacting with N,N,N'N'-tetramethylethylenediamine (TMEDA) and N,N,N'N'-tetramethyl-1,6-hexanediamine (TMHDA), respectively. The results of orthogonal experiments showed that temperature and time were the key factors influencing on epoxy value and quaternarization ratio respectively. The optimal condition for higher epoxy value was the reaction temperature at 15 °C and methanol as solvent. The reaction kinetic process was determined by conductivity, which showed that the reaction had a short induction period and appeared discontinuity in progress that the reaction rate of the first stage was almost constant, while the reaction rate of the second stage decreased gradually. The product was characterized by infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR). The results of surface tension testing showed that DEpDQAS-6 with longer spacer chain had better surface activity and lowered the solution surface tension to 26 mN·m−1 at 25 °C and CMC 0.27 mol·L−1. The thermodynamic parameters of micellization were obtained basing on charged pseudo-phase model. The studies of cytotoxicity in vitro and antibacterial activity showed that DEpDQAS was biocompatible and its antibacterial activity was more effective against Escherichia coli than against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Glycidyl trimethyl ammonium chloride-modified chitosan (GMAC-m-CS) was synthesized through nucleophilic substitution of GMAC on CS in isopropanol dispersed system, which was characterized by FTIR and1H NMR methods. The interaction between GMAC-m-CS and surface active ILs −1-dodecyl (tetradecyl and hexadecyl)-3-methylimidazolium bromide (CnmimBr,n = 12, 14, 16) was studied by surface tension and conductivity methods. The amount of CnmimBr adsorbed on GMAC-m-CS increases first with raising temperature, and then decreases, which reaches the largest amount at 30°C. The amount increases with the increase of alkyl chain length. The surface tension reducing capabilities of GMAC-m-CS/CnmimBr systems increase with temperature, however, decrease with the increase of GMAC-m-CS concentration. The aggregation processes of C14mimBr in solutions without GMAC-m-CS and with high concentration of GMAC-m-CS were entropy driven; however, it is enthalpy driven in solutions with low concentration of GMAC-m-CS. Based on the analysis of properties of GMAC-m-CS/CnmimBr, the interaction model of GMAC-m-CS/ILs was proposed. [ABSTRACT FROM PUBLISHER]

Epoxypropyl dodecyl dimethyl ammonium chloride (EPDDMAC) was synthesized withN,N-dimethyl dodecyl amine (DMDA) and epichlorohydrin (EPIC). Diethyl-2,3-epoxypropyl-[3-methyldimethoxyl)] silpropyl ammonium chloride (DEEPSAC) was synthesized withN,N-diethyl-aminopropyl-methyldimethoxysilane (DEAPMDES) and epichlorohydrin (EPIC). The products were characterized by infrared and elemental analysis and1H NMR spectroscopy. The surface tension, conductivity, and antibacterial activities of EPDDMAC and DEEPSAC were studied. [ABSTRACT FROM AUTHOR]

A novel class of organosilicon quaternary gemini surfactants alkanediyl-α, ω-bis(methyl-dimethoxy-silopropyl-diethyl ammonium bromide) was synthesized with N,N-diethyl-aminopropyl-methyl-dimethoxysilane and α, ω-dibromoalkane as the raw materials, where the N,N-diethyl-aminopropyl-methyl-dimethoxysilane was synthesized by reacting diethylamine with γ-chloropropylmethyldimethoxysilane. The effects of various solvents on the conversion rate of the reaction and on purification of surfactants were investigated. The structures of the organosilicon quaternary ammonium gemini surfactants were determined by means of 1H NMR and elemental analysis. The properties of aqueous solution were measured with electrical conductivity and viscosity methods. [ABSTRACT FROM AUTHOR]