Aspects of suspension stability

Suspension stability is governed by the same forces as in other disperse systems such as emulsions. There are differences, however, as coalescence obviously cannot occur in suspensions the adsorption of stabilising polymers and surfactants may also occur in a different 

Chapter 7 Emulsions, suspensions and other disperse systems 

Most suspension particles dispersed in water have a charge acquired by specific adsorption 

The velocity of migration of the particles (/Tg) under unit applied potential can be determined microscopically with a timing device and an eyepiece graticule. For nonconducting particles, the Henry equation is used to obtain 5 from /Tg. This equation can be written in the form 

The zeta potential (0 is not the surface potential (ipo) discussed earlier but is related to it. Therefore can be used as a reliable guide to the magnitude of electric repulsive forces between particles. Changes in on the addition of flocculating agents, surfactants and other additives can then be used to predict the stability of the system. 

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