Synthesis of New Deuterated Organic Comonomers and Deuterated High Sulfur Content Polymers for Optics and Photonics

This technology is new molecular design approach to prepare high refractive index polymers with enhanced medium wavelength infrared (MWIR) and/or long wavelength infrared (LWIR) transparency that are prepared from reacting with elemental sulfur with deuterated comonomers.  The polymers described herein are chalcogenide hybrid inorganic organic polymers (CHIPs) with enhanced MWIR and/or LWIR transparency and thermomechanical properties via the inverse vulcanization of elemental sulfur with new organic comonomers. To demonstrate the benefits of deuteration for IR optics, both proteo- and deutero-poly(S-r-DIB) copolymers operating at 3.4 µm and optical diffraction gratings were prepared from both materials.  This is the first demonstration of a functional IR optical element made from a CHIPs polymer that has been deuterated.

Background:
Optical technologies in the medium wavelength infrared (MWIR, 3-5 µm) and long wavelength infrared (LWIR spectrum, 7-14 µm) offer important advantages for high resolution thermal imaging in near, or complete darkness, which has been extensively utilized in the defence sector, but has significant potential in emerging consumer markets and transportation.    Current transmissive materials used for IR imaging are based on inorganic materials, such as, germanium (Ge), or chalcogenide glasses (ChG’s).  The use of polymeric transmissive materials would offer numerous cost and processing advantages, but historically have suffered from inferior optical properties and low transparency in the LWIR spectrum.  A major challenge in the design of LWIR transparent organic materials is the fact that nearly all organic molecules absorb in this spectral window which lies within the “IR fingerprint region” (e.g., 600-1400 cm-1). 

Applications:

• LWIR optical polymers
• MWIR optical polymers
• Use in photonic devices, such as waveguides, optical grating, ring-resonators, thermal imaging

Advantages:

• High refractive index
• Can be molded or solution processed into a fabricated optical element
• Improved IR transmission over non-deuterated material