Chalcogenide-Based Hybrid Polymers with High Refractive Index for IR Thermal Imaging

University Of Arizona, Tucson AZ

Investigators

Abstract

NON-TECHNICAL SUMMARY: This collaborative project project aims to prepare a novel class of polymeric materials that are derived from sulfur or selenium-based feedstocks. These materials will afford advanced new polymers with special optical and thermomechanical properties that can be used as lenses, windows, or other device components for thermal imaging. in the mid-infrared range. Infrared (IR) optical devices are widely used in optical communications, as well as in defense applications that require high-resolution imaging under conditions of pure darkness. NSF support of this project will enable fundamental insights into the key parameters required to control the properties (optical, mechanical, thermal) of these materials that will be essential for use in IR imaging applications. The advances from the project are anticipated to enable the creation of new IR devices and applications that are inaccessible with the inorganic materials that are currently used. The close integration of fundamental scientific research with cutting-edge IR technological problems will serve as a broader framework to train the students working on the project and expose K-12 students to aspects of polymer science through educational outreach activities. TECHNICAL SUMMARY: This collaborative interdisciplinary group will investigate the development of a new class of chalcogenide-based copolymers with very high refractive index (n greater than 2.0 in the visible and IR spectrum) and high IR transparency so as to afford a new class of optical polymers for use in mid-IR thermal imaging. Infrared (IR) optical technology is widely used in optical communications as well as in military and defense applications that require high-resolution imaging under conditions of pure darkness. Currently, synthetic polymers cannot be used as transmitting materials for mid-IR imaging applications as lenses or other device components since these materials strongly absorb IR radiation in the spectral window (3-5 micrometers) required for thermal imaging. In the proposed research, the PIs will investigate the copolymerizations of molten elemental sulfur (S8) together with other chalcogenide comonomers to increase the refractive index of these materials. Conversely, copolymerization of chalcogenide monomers with trivinylic or halogenated styrenic comonomers will also be conducted to lower the C-H content in these copolymers and ultimately increase the IR transparency of the resulting optical materials in the 3-5 micrometer mid-IR regime.