| 초록 |
This work confirms that the sorption process in the 3Y-TZP surface does not occur with the addition of Polyvinylpyrrolidone (PVP) into the suspension thus hindering the suspension stability by increasing the agglomeration formation in the 3Y-TZP suspension. The inability of PVP in the sorption process on the 3Y-TZP particle surfaces motivated us to use PVP as a depletion stabilization carrier to improve the suspension stability. As unusual to the previous studies of depletion stabilization which is used a high concentration of non-adsorbing polymer to prevent the agglomerating formation. Here in our study, we firstly modified the 3Y-TZP surfaces by addition of dispersants such as Ammonium Polyacrylate (APA) and Diammonium Citrate (DAC). The carboxyl group contents in PVP and DAC will introduce a negatively charge into the 3Y-TZP particle surface and prevent the agglomeration between the particles. The reaction between PVP and the 3Y-TZP surface which has a negatively surface charge has been studied. The optimum condition of dispersants has been found to produce a high stability of suspension owing to a combination of steric/electrostatic and depletion stabilizations and found that PVP only induces depletion stabilization in 3Y-TZP suspension stabilized with APA. To complete the comprehension of this study, the prepared suspensions were used to form sintered bodies and finally, the properties of the sintered bodies were examined by BET surface area, SEM, density, and Vickers hardness analyses. Here, we confirm that better suspension properties resulted in better-sintered body properties. |
