الفهرس 
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Abstract
SUMMARY
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The main problem in the mining processes converting the big size of the rocks to the small size of the rocks to complete the extraction process of the ore. The old version of cracking these rocks by using trinitrotoluene and the gum powder which are named primary and secondary explosives and there are have many disadvantages and very dangerous in uses in the mining operations. The modern blasting in the mining processes using the emulsion explosive, which is consist of continuous phase and the dispersed phase, the rang of the continuous phase is (7-8%) and the rang of the dispersed phase is (92-93%), so it is more economic than the classical explosives, in addition have a nemours advantage in usage, handling, velocity of detonation and safety in storage. For all these advantages in the above our goal in this work synthesis of some emulsifiers and evaluation of its performance in mining. This work includes the synthesis of six non-ionic emulsifiers based on polyisobutylene succinic anhydride by the alder-ene reaction of the polyisobutylene (M.wt. = 1000) with maleic anhydride under 200 0C for 24 hours. The chemical structure of this compound was confirmed by FT-IR spectra. After that, synthesis of non-ionic emulsifiers via two steps:
- First step: By esterification of the polyisobutylene succinic anhydride with different molecular weight of glycols (mono, di, polyethylene glycol 200, polyethylene glycol 400 and polyethylene glycol 600) under (100-120 0C) in presence of PTSA as catalyst to give five non-ionic emulsifiers named (E1, E2, E3, E4 and E5 )
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- Second step: By amidation of the polyisobutylene succinic anhydride with diethanol amine under (80 0C) in presence of PTSA to get non-ionic emulsifier (E6). The chemical structure of the prepared emulsifiers were confirmed by FT-IR spectra. The preparation of highly concentrated (W/O) emulsion by the dispersed phase (7.6%) and continuous phase (92.4%) with 10% & 14% of the prepared emulsifiers.
The emulsion stability was assessed on the HLB numbers. The interfacial and thermodynamic parameters of the prepared emulsifiers were determined at 30 0C including interfacial tension (γ), effectiveness (π), maximum surface excess (Γmax) and minimum surface area (A min). In addition, the standard free energies of micellization and adsorption were recorded. The data of the interfacial tension values decrease by decreasing the concentration of the emulsifiers until reach CMC and (A min) increased due to the ethylene oxide units. Also, the values of ΔGmic and ΔGads decreasing according to the hydrophilic moiety of the ethylene oxide units for non-ionic emulsifiers. So, the prepared emulsifiers E3 and E6 are preferred to adsorb rather than the other prepared emulsifiers. from the obtained data was observed that, E3 reduce the interfacial more than E6, this may be due to the ethylene glycol moiety. The droplet size distribution (DSD) of the prepared emulsion measured by (Malvern master sizer 2000). The obtained results showed that, the decrease of the droplet size with the minimize of the interfacial tension of the emulsifier E3 than E6 at the
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concentration 14% and 10%. The rheogical properties of the prepared emulsion also study by studying the shear rate – shear stress curves, shear strain – shear stress curves and shear rate – viscosity curves. The data revealed that the 14% of emulsifier E3 and 14% of emulsifier E6 are better than 10% of emulsifier E3 and 10% E6 of emulsifier respectively. For the fresh emulsion and aged emulsion and have shear thinning and non-Newtonian behaviors, moreover, the viscoelastic studies and amplitude sweep test were study for the prepared emulsion with 14% of emulsifier E3 and 14% of emulsifier E6. The data showed that, the viscoelastic region are more stable than 10% of emulsifier E3 and 10% of emulsifier E6 respectively. Which is lead to the G’ and G’’ have a good results for emulsifier E3 and emulsifier E6. The optical microscopy images of the prepared emulsion from 10% of emulsifier E3 and 10% of emulsifier E6 and 14% of emulsifier E3 and 14% of emulsifier E6 respectively are illustrated that, the emulsion droplets are polyhedral and polydisperse in a continuous phase. from all the data, it is clear that the prepared emulsion (fresh and aged) 14% of emulsifier E3 and 14% of emulsifier E6 are better in all results.