초록 ▼

A core/shell polymer is capable of increasing a composition\s whiteness or opacity. The core and shell polymers have either a crystalline structure or have a Tg of at least about 50°C. The core polymer has a different composition than the composition of the shell polymer. The core polymer comprises

A core/shell polymer is capable of increasing a composition\s whiteness or opacity. The core and shell polymers have either a crystalline structure or have a Tg of at least about 50°C. The core polymer has a different composition than the composition of the shell polymer. The core polymer comprises vinylidene halide monomers and/or vinyl halide monomers. The core and shell polymers are either homopolymers or copolymers.

대표청구항 ▼

An opaque core/shell polymer comprising: (a) a non-swellable core polymer having an outer surface and a Tg of at least about 50°C., and comprising a vinyl halide monomer; and (b) a shell polymer in physical contact with and covering the outer surface of at least a part of the core polymer, the shell

An opaque core/shell polymer comprising: (a) a non-swellable core polymer having an outer surface and a Tg of at least about 50°C., and comprising a vinyl halide monomer; and (b) a shell polymer in physical contact with and covering the outer surface of at least a part of the core polymer, the shell polymer (i) comprising a sufficient vinylidene chloride monomer concentration so that the shell polymer has a crystalline structure and (ii) having a different composition from that of the core polymer, wherein the weight percent of the core polymer, based upon the total weight of the opaque polymer is less than the weight percent of the shell polymer, and the opaque polymer has a particle size of about 200 to about 1,000 nm.