Patent attributes
A process for encapsulating metal microparticles in a pH sensitive polymer matrix using a suspension containing the polymer. The process first disperses the metal particles in a polymeric solution consisting of a pH sensitive polymer. The particles are then encapsulated in the form of micro-spheres of about 5-10 microns in diameter comprising the pH sensitive polymer and the metal ions (Ni2+, Cu2+) to be coated. The encapsulated matrix includes first metal particles homogeneously dispersed in a pH sensitive matrix, comprising the second metal ions. A high shear homogenization process ensures homogenization of the aqueous mixture resulting in uniform particle encapsulation. The encapsulated powder may be formed using spray drying. The powder may be then coated in a controlled aqueous media using an electroless deposition process. The polymer is removed when the encapsulated micro-spheres encounter a pH change in the aqueous solution.
