الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Surface active agents are considered as important compounds which have important applications in various industrial fields. In addition to participate in the formulation of emulsions and phase transfer catalysis, surface active agents are used as biocides to inhibit or kill the growth of bacteria and fungi. As a result of the integrated usage of the surface-active agents in several industrial fields, their improvement was urgent to synthesize new types which characterized by higher efficiency in their applications and also to decrease the used dose. The unique improvement of the surface-active agents was introducing cationic groups in their skeleton as well as self-assembled on the silver nanoparticles to improve their adsorption at the different surfaces. That increased their efficiency as biocides considerably.
The main results concluded from this thesis can be summarized in the following topics:
1. A series of cationic surfactants was synthesized based on methyl diethanol amine and have a different alkyl chain length (decyl, dodecyl, tetradecyl and hexadodecyl) in their hydrophobic moiety.
2. The chemical structure of the synthesized surfactants was confirmed using FT-IR and 1H-NMR spectroscopy tools.
3. The colloidal solution of the silver nanoparticles (AgNPs) was prepared using chemical reduction method for silver nitrates (AgNO3).
4. The self-assembling of the synthesized surfactants on the prepared AgNPs to form nanoshells was confirmed using the FT-IR, UV spectra, TEM and DLS techniques.
5. The MDABC, MDABL, MDABM and MDABP surfactants showed effective role in controlling the silver nanoparticle formation, where the surfactant MDABP produced silver nanoparticles with smaller size in the range of 6-15 nm with uniform distribution.
6. The surface tension results show the influence of the synthesized surfactants on the surface activity.
7. The surfactant tail plays important role in controlling the micelliztion and adsorption tendency of the cationic surfactant.
8. The thermodynamics disclosed the adsorption priority at the interface then they move to the bulk for micelle formation.
9. The antibacterial evaluation of the synthesized compounds demonstrated that the biological activities of the synthesized compounds were influenced by the presence of the benzene ring, positive charge and hydrophobic chain in the chemical structures of these biocides increases their biocidal activities considerably.
10. The antibacterial results show also the improvement in the antibacterial activity of the synthesized surfactants using their nanostructures with the AgNPs.
11. The synthesized MDABC, MDABL, MDABM and MDABP showed good killing action against sulphate reducing bacteria (SRB).