Study On Preparation And Characterization Of Environment-friendly Ionic Polymer Ceramic Dispersant

In order to improve production conditions and enhance the quality of ceramicproducts in ceramic industry, dispersants are often needed to add to satisfy the productionrequirements of high solid content, low viscosity for ceramic slurry. The polymerdispersant containing the characteristics of excellent dispersion property and designedmolecular structures, has become the development direction of new economy greenpolymer dispersant.Cationic polymer dispersant (PHD) was synthesized by using hydroxyethyl cellulose(HEC) as raw material with dimethyl diallyl ammonium chloride (DMDAAC) as graftcopolymerization monomer. The viscosity of kaolin slurry experiment as indicator isemployed to obtain the optimum reaction conditions, i.e. when the reaction temperature is75℃, the mass ratios of HEC/DMDAAC, KPS and NaOH are3.3%,2%and2%afterreaction for4h, respectively. And FI-IR analysis results show that the product is PHD.P(St/HA/AA) and P(HA/AA) were synthesized by employing starch as raw materialwith anionic monomers of sodium humate and acrylic acid. The best synthesis conditionsof P(St/HA/AA) are that after reaction2h at70℃, the mass ratios of St/(AA&HA),HA/AA and KPS are1:30,3:1and7%, respectively. FT-IR analysis results show that as-synthesized sample is pure. The optimum synthesis conditions for P(HA/AA) is when thereaction temperature is70℃, the mass ratios of HA/AA and KPS are3:1and11%afterreaction for3h, respectively. FT-IR results indicated that P(St/HA/AA) and P(HA/AA)are synthesized successfully.The experiment results demonstrate that the thixotropy of70%solid content ofkaolin slurry is strongly affected by concentrations of poly-dispersant. When PHD ratiosrange from0.1%to0.9%, the thixotropy of kaolin slurry changes from negative passingthrough complex to weak negative again, the thixotropy of kaolin slurry withP(St/HA/AA) as dispersant varies from complex to positive to weak negative, however,thixotropic type of kaolin slurry along P(HA/AA) as dispersant transforms from negativethixotropy to complex thixotropy, then back to weak negative thixotropy. And addition ofdispersant can obviously increase the Zeta potential absolute value of kaolin slurry. It isalso observed that PHD is suitable for acidic system, while P(St/HA/AA) and P(HA/AA)are fit for alkaline system. Rheological characteristic of the kaolin slurry followsBingham model when the addition of P(HA/AA), P(St/HA/AA) and PHD are all0.5%.