Initiated chemical vapor deposition of vinyl polymers for the encapsulation of particles

摘要

Described herein are all-dry encapsulation methods that enable well-defined polymers to be applied around particles. One aspect of the invention relates to a method of coating a particle, comprising the steps of: placing said particle in a vessel at a pressure; rotating said vessel at a rotating speed for a period of time; mixing together a first gaseous monomer at a first flow rate, and a gaseous initiator at a second flow rate, thereby forming a mixture; introducing said mixture into said vessel via a vapor feedline; heating said mixture, thereby forming a reactive mixture; contacting said particle with said reactive mixture; thereby forming a polymer coating on said particle. The methods may be modified forms of initiated chemical vapor deposition using a thermally-initiated radical polymerization to create conformal coatings around individual particles while avoiding agglomeration. Particle surfaces may be coated with a range of functional groups.

主权项

1. A method, comprising the steps of:
placing a plurality of individual particles in a vessel at a pressure; wherein said vessel comprises a vapor feedline for delivering vapors into said vessel through exit holes, and a filament in proximity to said exit holes; the individual particles consist of soda glass, silica, carbon, or a drug; and the diameters of said individual particles are about 5 μm to about 35 μm; contacting said vessel with a water bath at a first temperature, wherein said first temperature is between about 0° C. and about 100° C.; rotating said vessel at a rotating speed for a period of time; mixing together a first gaseous monomer at a first flow rate, and a gaseous initiator at a second flow rate, thereby forming a mixture; introducing said mixture into said vessel via said vapor feedline which comprises said filament at a second temperature, wherein said second temperature is between about 150° C. and 350° C.; heating said mixture with said filament, thereby forming a reactive mixture; contacting said plurality of individual particles with said reactive mixture; thereby forming a plurality of individual coated particles, wherein each individual coated particle consists of a substantially uniform polymer coating encapsulating one individual particle; the thickness of said substantially uniform polymer coating is about 3 μm to about 12 μm; each individual particle is non-agglomerated; and the plurality of individual coated particles is non-agglomerated.