skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Photochemistry of tertiary nitrosoalkanes in solid polymer matrices: a promising new class of organic materials for holographic recording with semiconductor lasers

Journal Article · · J. Am. Chem. Soc.; (United States)
DOI:https://doi.org/10.1021/ja00255a038· OSTI ID:5527111

The authors have investigated a new class of photopolymers for near-infrared (near IR) holographic recording: three members of the tertiary nitrosoalkanes (RNO) dissolved in two different poly(alkyl ..cap alpha..-cyanoacrylates) (p-(alkyl-CAc)). Absorption/transmission spectroscopy, a CW holographic technique (PIH), and a newly developed phase-sensitive holographic technique, phase-modulated holography (PMH), were employed in these investigations. The last technique is an ideal tool for the investigation of photopolymer systems because it allows one to monitor separately and simultaneously the amplitude and phase contributions to the holographic grating and thus to monitor simultaneously the photoreaction of the RNO and the resulting holographic recording mechanism. The RNO in p-(alkyl-CAc) undergo a homolytic dissociation after absorption of one photon at wavelengths up to 799 nm. The corresponding photochemical rates, the quantum yields, and the activation energies were determined and were found to depend strongly on the glass transition temperature of the polymer solvent. However, hologram formation arises not only from the photoreaction of the RNO but mainly from a photoinduced expansion of the polymer matrix, i.e., a photomechanical effect. The resulting density change, which is associated with a large change of refractive index, does not depend on the RNO but on the matrix only. The near-IR holographic sensitivities of the new photopolymers were determined. They are high due to the considerable photomechanical effect, allowing one to write holographic gratings with a GaAlAs semiconductor laser at 788 nm.

Research Organization:
Universitaet Muenchen, Germany, F.R.
OSTI ID:
5527111
Journal Information:
J. Am. Chem. Soc.; (United States), Vol. 109:21
Country of Publication:
United States
Language:
English