Polymer Assembly

High Chi Block Co-polymers

Microchips, or integrated circuits, have transformed the world of electronics and are found in virtually all modern electronic devices. Among the most advanced integrated circuits are the microprocessors or “cores” that control our computers and cellular phones, devices that are an essential part of modern lives. Industry is constantly working to improve these devices by packing more circuitry into their chips to decrease device cost and increase speed. Increased density of circuitry presents several challenges, including the need to produce smaller feature sizes and to inscribe more complicated patterns. The Hawker group is working to produce smaller features by improving the synthesis and self-assembly of high χ block copolymers. For example, we investigated the self-assembly of poly(dimethylsiloxane-block-methyl methacrylate), synthesized via “click” chemistry, to produce highly ordered patterns with domain periods as small as 12.1 nm, which is among the smallest highly ordered nanoscale patterns reported. This work was expanded by introducing an ionic salt at the junction of the two blocks. The electrostatic interactions between the domain junctions of the polymer chains lead to increased enthalpy, segregation strength, and phase separation.

Polymeric Nanoparticles

Nature’s ability to precisely control the shape and functionality of nanoparticles in a range of biological systems has motivated researchers to achieve similar control in artificial systems. Specifically, control over polymeric nanoparticles is critical to applications ranging from drug delivery to artificial camouflage. We demonstrated a facile method to control particle shape and morphology through the use of PS-b-P2VP and tailored, mixed surfactant systems to tune surface interactions. The simplicity and generality of this synthetic strategy allows access to novel, shape-anisotropic and responsive polymer particles.