Critical Coagulation Concentration of Polystyrene Particles

• Main Author: 廖抱元
• Other Authors: 徐治平
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/95003493703108368837

碩士 === 國立臺灣大學 === 化學工程研究所 === 84 === The coagulation behaviors of polystyrene particles in electrolyte solutions is examined both theoretically and experimentally.　 In particular, the effects of the valence of counterion and the linear size of particle on the critical coagulation concentration (CCC) of counterions are analyzed. The latter is estimated through defining a critical mean particle size, which can be measured experimentally. 　Two approaches are adopted to estimate the theoretical CCC value: one is based on the Derjaguin approximation, and the other on a pertubation method. The result of experimental observations reveals that the CCC for counterions either decreases with the increase in particle size, or has a maximum. For divalent and trivalent counterions, the experimental value of CCC is lower than that predicted by theory analyses. For larger particles, the predicted CCC ratio for counterions is closer to that predicted by theory than smaller particles. The zeta potential of polystyrene particles is measured, which provides some evidence for the assumption that the coagulation phenomenon under consideration is mainly due to the compression of electrical double layers.