Zinc stearate is a highly versatile material that can be used in a variety of industries. It is a lubricant, water repellent, heat stabilizer and release agent. It is also an effective pigment dispersion aid and lubricant in plastics production.
A Process For Stable Aqueous Dispersion Of ZnSt Particles In A Water-Based Preparation
Typically, an aqueous zinc stearate dispersion is prepared by homogenizing (emulsifying) a mixture of zinc stearate particles in a high-pressure reactor. The zinc stearate is then heated to 140-180 DEG C. and stirred for 1 hour at this temperature. The zinc stearate is then rapidly cooled and discharged.
This method requires the use of a commercial high-pressure homogenizer and a separate high-pressure reactor system. This combination is very expensive and wears down the equipment quickly.
A more economical and less abrasive method of preparing an aqueous zinc stearate particles dispersion is described. In this method, the zinc stearate is introduced into a mixture including metal-containing stearate first and then the zinc salt is introduced afterward.
This technique is faster than the particle size reduction method (homogenization) and avoids the need for a commercial high-pressure homogenizer as well as the high temperature and pressure requirements of the homogenization procedure. Additionally, the stable aqueous dispersion can be prepared in a much shorter time (from about 2 hours to less than an hour). The process has many advantages: