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Nonconjugated conductive polymers have unique characteristics for providing protection against nuclear radiation including radioactive iodine (carcinogenic) which remains in vapor phase at and above room temperature and is difficult to contain. When iodine comes in contact with such a polymer, a charge-transfer occurs between the double bond and iodine, and as a consequence, the iodine atoms become bound to the polymer chain. Large films/sheets of these polymers covering nuclear reactors and waste storage facilities will act as effective shields against radioactive iodine since iodine atoms will be captured by these polymers and will not be able to escape to the environment. In addition, apparels made of these polymers will reduce exposure to radioactive iodine for doctors, nurses, attendees, and visitors during and after radioiodine therapy of thyroid patients. Thus, these polymeric shields should protect lives and the environment and reduce or avoid the exposure to humans in case of iodine releases from nuclear reactors: in normal day-to-day operations, due to accidents, and in disasters up to the magnitude of Fukushima Daiichi and Chernobyl.

Electroabsorption in metallic nanoparticles within transparent dielectric media has been measured. In particular, gold nanoparticles in glass and subnanometer-size metallic domains in iodine doped nonconjugated conductive polymer have been studied. Measurements have been made for applied ac fields at 4 kHz, at a wavelength close to the onset of the surface plasmon resonance. The measured electroabsorption (imaginary part of χ(3) or Kerr coefficient) has a quadratic dependence on electric field. Its magnitudes were compared for different sizes of the metallic nanoparticles down to the subnanometer-size particles in iodine-doped nonconjugated conductive polymer. As in the case of quadratic electro-optic effect reported earlier, electroabsorption has approximately a 1/d3 dependence, d being the diameter of nanoparticle. This is consistent with existing theories on confined metallic systems.

The quadratic electro-optic effect/Kerr coefficients were measured for the first time for metal nanoparticles. In particular, gold nanoparticles in glass were studied. Measurements were made using the field-induced birefringence method at a wavelength near the onset of the surface plasmon resonance. The magnitudes of the Kerr coefficients for different sizes of gold nanoparticles in glass were measured and compared with that of subnanometer size metallic particles in non-conjugated conductive polymers. The magnitude of the Kerr coefficient was found to increase rapidly (about d−3) when the diameter, d, of the nanoparticles was decreased. This is consistent with the existing theories and understanding of nonlinear optics in metal nanoparticles. The results imply a broad range of new applications of metal nanoparticles in electro-optic switching/modulation, low-cost Kerr cells and other uses in optoelectronics.