Photochromic Switching for Nanostructured Polymer Gels

Rensselaer Polytechnic Institute, Troy NY

Investigators

Abstract

Controlling the shape and arrangement of materials at sizes roughly a thousandth of the thickness of a human hair is a much sought after capability in advanced manufacturing. The only commercial instrument capable of controlling the shape and arrangement of these nanometer-sized materials is both expensive (~$50 million) and prohibitively slow due to their requirement for use on flat surfaces. A potentially transformative alternate method that is not subject to these severe constraints is hampered by a lack of understanding of the chemistry involved in the synthesis of the materials. The paucity of knowledge on these syntheses is targeted by studying and controlling the speeds at which the relevant chemical reactions occur. Additionally, this project educates participating graduate and undergraduate students in state of the art chemistry techniques. K-8 students are inspired to consider careers in science and engineering while working with their families on research-themed. household material-based activities that are available through a widely accessible online portal. The central aim of this project is to develop a fundamental understanding of the underlying chemical kinetics needed to enable 3-dimensional interference lithography with a resolution beyond the diffraction barrier. The key requirement is a reversible and saturable reaction accompanied by a material-writing step. Reaction rates are controlled by manipulating the steric and electronic nature of substituents on the monomer, and tailoring the chemical structures of the other key active components (e.g., polymers and crosslinking agents). The objectives of this research include the synthesis of a combinatorial library of monomer derivatives with systematically varied steric and electronic properties; quantification of the kinetics of nanometer-sized material growth, with the goal of obtaining rapid and saturable equilibrium under low laser intensities; and polymerization of diffraction unlimited features over large areas.