Carnegie Mellon University

Jeffrey Pyun

Krzysztof A Matyjaszewski

Scott G Gaynor

Xuan Zhang

Jianhui Xia

Tomislav Pintauer

Jian Qiu

Mircea Teodorescu

Peter J Miller

Hyun-jong Paik

Further improvements have been made in processes for controlled polymerization of free radically (co)polymerizable monomers mediated by a transition metal complex participating in a redox reaction which involves transfer of a radically transferable atom or group to and from an initiator or dormant polymer and the growing active polymer chain ends. Two improvements involve the choice of counterion in the transition metal complex. In one improvement the transition metal is held in close conjunction with a solid support through interaction with a counterion directly attached to the support. This cognition also allows for improvements in catalyst utilization including catalyst recovery and recycle. In another improvement, particularly suitable for controlled polymerization of certain monomers with an expanded range of transition metals, the function of counterion and ligand in the development of the transition metal based catalyst is superseded by use of salt containing a soluble organic counterion. These and other process improvements have been employed to prepare an extended range of novel polymeric materials and novel processes for the preparation of functional polymers including a novel catalytic Atom Transfer Coupling Reaction.

Catalytic processes for the controlled polymerization of free radically (co)polymerizable monomers and functional polymeric systems prepared thereby

The present invention describes preparation of nanocomposite particles and structures by polymerizing monomers onto a functional inorganic colloid comprising a polymerization initiation site. The polymerization process is preferably a controlled/living polymerization process, including but not limited to, atom transfer radical polymerization and stable free radical polymerization. The nanocomposite particles can self-organize in solution, on surfaces or in films forming nanocomposite structures. Tethered AB block nanocomposite particles bring size control, solubility control and control over micro- and macro-functionality to the particles. The process may be catalyzed by a transition metal complex which participates in a reversible redox cycle with at least one of the group and a compound having a radically transferable atom or group, to form a nanocomposite particle with a tethered polymer chain. The process may be continued to form tethered copolymer chain. The particle may be silicon based including, for example, silica, silicates and polysilsesquioxane. A nanocomposite structure may be formed by casting, depositing or forming the material including nanocomposite particles.

Preparation of nanocomposite structures by controlled polymerization

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Pittsburgh, PA, United States of America

Jeffrey Pyun