Suspension concentration is a kind of water-based formulation used widely for its high efficacy and low cost, which is gradually becoming a hot research spot and development quickly in the world. Niclosamide ethanolamine is the only chemical recommended by World Health Organization (WHO) to control intermediate host of schistosomiasis for killing snails, so as niclosamide ethanolamine salt. However, in the research and development process, the particles coalesce larger, solid-liquid separation, thickening agglomeration physical storage stability issues has always been a bottleneck restricting the development of its slower development.In this thesis, we made25%niclosamide ethanolamine salt SC, measured the average particle, zeta potential, adsorption amount at different conditions, we found that salt ions, pH, temperature and other factors affecting its dispersion stability and its rheological and thixotropic property. We made several conclusions as follows:1. Flowing point test and laser granulometry were used to identify dispersing agents, the amount of dispersants were determined by the viscosity method. PVP is the suitable dispersant for niclosamide ethanolamine salt SC. When the molecular weight of PVP is K15, the optimum ratio of the polymer is0.5-2.5%, when its molecular weight is K30, the optimum ratio is0.5-1.5%.2. Dispersant different molecular weight, temperature, pH and other factors could infect on suspension stability.(1) attapulgite can change the fluid behaviour, after adding attapulgite, the viscosity decreases with increasing shear rate, indicating its Newtonian fluid, fitting with Herschel-Buckley model well.(2) PVP can be used to make niclosamide ethanolamine salt suspensions, the higher the molecular weight, the greater the viscosity value is.(3) changes in temperature have a significant effect on the niclosamide ethanolamine salt suspension system viscosity and rheology parameters. The higher the temperature is, the lower the viscosity of the system is.(4) pH has a significant influence on the viscosity and rheology parameters in niclosamide ethanolamine salt suspension system. As the pH increases, the viscosity climbs up and then decline.3. Found the milling time, the dispersant molecular weight, the dispersant dosage, pH, salt ions, temperature and other factors can influence dispersion stability on the niclosamine ethanolamine salt suspensions.(1) milling time impact on particle size greatly and its particle size decreases with the growth of the milling time, when the milling time is2h, the particle size did not change significantly.(2) the molecular weight of PVP effect on niclosamide ethanolamine salt SC dispersion is closely related to the amount of its dosage, when use PVP K15as dispersant, the addition of between0.5%to2.5%, when use PVP K30as dispersant, the amount of between0.5%-1.5%.(3) pH has a great effect on dispersion stability in the niclosamide ethanolamine salt suspensions, when pH value increases, system size showed smaller decreases after the first tendency and Zeta potential showed smaller increases after the first tendency, when pH=9.0, niclosamide ethanolamine salt suspensions appear Zeta potential maximum, minimum average particle size, dispersion stability is best.(4) at different pH different concentration of NaCl, CaCl2added to niclosamide ethanolamine salt, average particle size increased after suspending the system of accelerated test, while dispersion stability deteriorate; CaCl2effect on the particle size of the system to be significantly on the system particle than NaCl.(5) PVP dispersant on niclosamide ethanolamine salt particles absorption related to its molecular weight, the higher molecular weight PVP, its adsorption capacity is also greater.(6) different temperatures effected in the adsorption isotherm of PVP to niclosamine ethanolamine salt particles interface, as a part of the double layer adsorption, when the dispersant concentration is low, it fitting the Langmuir adsorption isotherm adsorption equation, Γ∞and K with decreases with increasing temperature.(7) at different pH, PVP adsorped on the niclosamine ethanolamine salt particles interface, the adsorption isotherms type is double-layer, at low dispersant concentrations, it fitting to the Langmuir adsorption isotherm adsorption equation,Γ∞and K and then decreased with increasing pH values. |