Opacifying particles with internal void and methods for making the same

摘要

The invention includes a method of preparing an aqueous dispersion of particles at least partially encapsulated by a polymer, the method comprising dispersing inorganic particles in an aqueous phase; functionalizing at least a portion of the surfaces of the inorganic particles with a coupling agent, the coupling agent having pendent reactive groups; polymerizing the reactive groups on the functionalized particles with a first polymerizable component to produce inner polymer shells surrounding the inorganic particles; polymerizing a second polymerizable component to form outer polymer shells at least partially encapsulating the inner polymer shells; and producing voids within the outer polymer shells, such that the inorganic particles are received within the voids.

主权项

1. An aqueous dispersion of particles comprising:
inorganic particles, each particle being at least partially encapsulated by an inner shell, wherein at least a portion of the surface of each particle comprises a coupling agent having a pendent reactive group, and wherein the inner shell is prepared from a reaction of the coupling agent pendent reactive group with an ethylenically unsaturated monomer; a first outer shell at least partially encapsulating each inner shell, the first outer shell defining a void; and a plurality of second outer polymer shells at least partially encapsulating the first outer shell, wherein the second outer polymer shells are at least partially spaced apart from the first outer shell by the void.