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

US9492805B2 · kind B2 · utility

Assignee

• Massachusetts Institute of Technology · US

Inventors

• Karen K. Gleason · Cambridge, US
• Kenneth Ka Shun Lau · Somerville, US

Key dates

• Filing date: Oct 30, 2006
• Grant date: Nov 15, 2016
• Expiry date: Oct 5, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C16/452
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

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.