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A series of cationic polyurethane surfactants [PQ8‐18] were synthesized by the reaction of alkyl bromoacetate (namely: octyl‐, decyl‐, dodecyl‐, tetradecyl‐, hexadecyl‐, and octadecyl bromoacetate) as quaternizing agents and modified polyurethane contains tertiary amine species. Modified polyurethane was prepared by the reaction of toluene diisocyanate (TDI) and triethanol amine monomercaptoacetate. The chemical structures of the prepared surfactants were confirmed using elemental analysis, Fourier transform infrared spectroscopy (FTIR), and Proton nuclear magnetic resonance (1H NMR) spectroscopy. The molecular weight measurements of the prepared polymers showed that the segments of each polymer contain average 10 units of the urethane‐triethanol amine mercaptoacetate. The surface activities of the prepared surfactants including: surface tension (γ), effectiveness (πcmc), concentration at micelle formation (CMC), efficiency (Pc20), maximum concentration at the interface (Γmax), and the average area occupied by each surfactant molecule at the interface at equilibrium (Amin) of surfactants solutions were established at 25°C. The surface tension and the critical micelle concentration values of the prepared surfactants were gradually decreased by the gradual increase of their alkyl chain length. The prepared cationic surfactants showed efficient activity as inhibitors for dissolution of carbon steel in an acidic medium and also as a biocide against the growth of bacteria, fungi, and yeast. [ABSTRACT FROM AUTHOR]

Metal nanoparticles have attracted considerable interest particularly because of the size dependence of physical and chemical properties and its enormous technological potential. Among different metal nanoparticles, copper nanoparticles have attracted great attention because copper is one of the most key metals in new technology. Chemical methods are used to synthesize copper nanoparticles. Chemical reduction is the most frequently applied method for the preparation of stable, colloidal dispersions in organic solvents. In this paper, the new cationic thiol polyurethane surfactants with different alkyl chain length were synthesized (PQ10, PQ14 and PQ18). The chemical structure of the synthesized surfactants was confirmed using infra-red spectroscopy (IR) and proton nuclear magnetic resonance spectroscopy (1HNMR). Copper nanoparticles colloidal solution of 40-80 nm diameters was prepared using sodium borohydride in aqueous solution at room temperature as reducing agent. The synthesized surfactants decrease the aggreegation of copper nanoparticles. The nanostructure of the synthesized surfactant with copper nanoparticles with diameters ranging from 31.5 to 10.3 nm was prepared and characterized using ultra violet spectrophotometer (UV), infra-red spectroscopy (IR) and transmission electron microscope (TEM). The results declare formation and stabilization of copper nanoparticle using synthesized cationic surfactants. Antimicrobial activity of the synthesized cationic surfactants and their nanostructure with copper nanoparticles were evaluated against pathogenic bacteria and fungi. [ABSTRACT FROM AUTHOR]