Preparation Of Quizalofop-p-ethyl Emulsion In Water And Its Forming Mechanism Of Physical Stable System

The thesis chose diflufenican as the research objects. We did more research about the physical stability of Emulsion in water from the rheological point of view. The following aspects were studied in this thesis:1. The stability of ethyl acetate emulsion and influence factor such as non-ionic emulsifier type and usage amount, pH value and electrolyte of the medium was studied. The results of zeta potential and mean particle size showed that when the usage amount of phenylethyl-phenol-polyoxyethylene-ether (NR603) was10%, the prepared emulsion was more stable. When the medium pH is5～6, the absolute zeta potential of emulsion droplet reached the maximum value, and the average particle size reached the minimum one. The effect of cations was greater than anions on the zeta potential and the mean particle size of emulsion droplet. The higher value of metal ions, the greater the impact on emulsion stability. Zeta potential had a good corresponding relationship with the average particle size of industrial-grade non-ionic emulsifiers in characterization the emulsion stability. The zeta potential can be adopted to evaluate the emulsion stability emulsified by non-ionic emulsifiers.2. Study the formulation and characterization of emulsion in water. Zeta potential method was used to select emulsifier in preparing12%quizalofop-p-ethyl EW concentrate in this study, the average particle diameter (Dav) of test system was determined using laser particle distribution instrument..According to the standard of inchoative appearance of initial praparation, emulsifiability and dispersibility, emulsion stability, cold storage, heat storage and ordinary storage, its optimum formulation was developed by the phase transfer method, through the screening of kinds of auxiliary agents(solution, emulsifier, thickening agent, anti-freeze agent), which is quizalofop-p-ethyl12%, acetic ether30%, NR603#10%, polyethylene glycol0.6%, ethylene glycol5%, and water else.3. Abstract the influences of mass fractions of Mg-Al HTLc (w), electrolytes(NaCl, CaCl2) and pH on the rheology and thixotropy of Quizalofop-P-ethyl EW were studied in this paper. It was found that the rheological behavior of Quizalofop-P-ethyl EW coincided with the Herschel-Buckley rheological model, and the EW showed the property of rheogram"shear-thinning"of the pseudo-plasticity, Consistency index K and yield value t0increased with the increase of w, and the EW displayed negative thixotropy when w reached a certain value; The electrolytes with various concen-tration exerted different effects on K and To, and the influences of CaCl2were more significant than NaCl at the same concentration. The property of rheogram shear-thinning of the pseudo-plasticity and Negative thixotropy of the EW added with electrolytes were not changed. with the increase of temperature, the property of rheogram"shear-thinning"of the pseudo-plasticity and negative thixotropy of the system were not changed.