Microencapsulated polyaniline particles for electrorheological materials

Homopolyaniline particles were microencapsulated with melamine-formaldehyde resin because microencapsulation entraps core liquid materials. Microencapsulated polyaniline particles were then used for the preparation of the electrorheological (ER) fluid. The ER properties of the microencapsulated polyaniline/silicone oil suspension were examined. The homopolyaniline at the low pH is unable to produce ER properties due to its high conductivity. The ER properties can be controlled by using melamine-formaldehyde resins without controlling the pH of the polyaniline.