Carnegie Mellon University

Ke Min

Krzysztof A Matyjaszewski

James Spanswick

Nicolay V Tsarevsky

Wojciech Jakubowski

Lindsay Bombalski

Jung Kwon Oh

Embodiments of the polymerization process of the present invention are directed to polymerizing free radically polymerizable monomers in the presence of a polymerization medium initially comprising at least one transition metal catalyst and an atom transfer radical polymerization initiator. The polymerization medium may additionally comprise a reducing agent. The reducing agent may be added initially or during the polymerization process in a continuous or intermittent manner. The polymerization process may further comprises reacting the reducing agent with at least one of the transition metal catalyst in an oxidized state and a compound comprising a radically transferable atom or group to form a compound that does not participate significantly in control of the polymerization process. Embodiments of the present invention comprise reacting a reducing agent with at least one of catalyst in an oxidized state and a compound comprising a radically transferable atom or group to initiate and/or maintain catalytic activity throughout the polymerization process.

Atom transfer radical polymerization process

Functional gel particle formed from a crosslinked polymeric network including a fraction of stable crosslinks and a second fraction of cleavable crosslinks are disclosed. Functional compounds may be chemically or physically encapsulated within and/or released from the gel particle by selective cleavage of the cleavable crosslinks. The functional compounds may be delivered and released to a pre-selected target site. Peripheral or other accessible functionality on the surface of the gel particle allows attachment of a surface reactive agent, thereby modifying one or more surface properties of the gel particle. Processes of preparing the gel particles and processes of delivering the functional compounds to a target site are also disclosed.

Preparation of functional gel particles with a dual crosslink network

The invention is directed to a microemulsion polymerization comprising adding a polymerization catalyst precursor, such as a transition metal complex in the higher of two accessible oxidation states, an ATRP initiator, and an organic solvent to an aqueous solution to form an emulsion. Radically polymerizable monomers and a reducing agent may then be added to the emulsion. The reducing agent converts the catalyst precursor to a catalyst for polymerization of the first monomer from the initiator. In certain embodiments the organic solvent may comprise radically polymerizable monomers. The aqueous solution may comprise a surfactant. Further embodiments are directed to an ah initio polymerization process comprising adding a polymerization catalyst precursor; an ATRP initiator, and an organic solvent to an aqueous solution to form an emulsion, wherein the organic solvent comprises second radically polymerizable monomers, adding a reducing agent to convert the catalyst precursor to a catalyst for polymerization of the first radically polymerizable monomer from the initiator; and adding first radically polymerizable monomers to the emulsion.

Atom transfer radical polymerization in microemulsion and true emulsion polymerization processes

The present disclosure describes a two-step batch dispersion polymerization process for the preparation of substantially uniformed-sized functional (co)polymer particles. The first step of the process includes polymerizing at least one first radically (co)polymerizable monomer by a free radical polymerization process to form a (co)polymer in a stable colloidal dispersion and the second step includes polymerizing the at first radically (co)polymerizable monomer or an additional radically (co)polymerizable monomer in the stable colloidal dispersion by a living/controlled radical (co)polymerization process.

Atom transfer dispersion polymerization

Embodiments of the polymerization process of the present invention are directed to polymerizing free radically polymerizable monomers in the presence of a polymerization medium initially comprising at least one transition metal catalyst and an atom transfer radical polymerization initiator. The polymerization medium may additionally comprise a reducing agent. The reducing agent may be added initially or during the polymerization process in a continuous or intermittent manner. The polymerization process may further comprise reacting the reducing agent with at least one of the transition metal catalyst in an oxidized state and a compound comprising a radically transferable atom or group to form a compound that does not participate significantly in control of the polymerization process. Embodiments of the present invention comprise reacting a reducing agent with at least one of catalyst in an oxidized state and a compound comprising a radically transferable atom or group to initiate and/or maintain catalytic activity throughout the polymerization process.

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Pittsburgh, PA, United States of America

Ke Min