Photochemical Image Storage in Polymer Liquid Crystals

Abstract
Amplified optical image storage has been demonstrated in polymer liquid crystals (PLC). A small amount (< 5 mol%) of a low molecular weight mesogen with a photoresponsive moiety, 4-butyl-4′-methoxyazobenzene (BMAB), was doped in the films of polyacrylates with mesogenic side chain, poly(4′-methoxyphenyl-4-acryloyloxyalkoxybenzoate)(PAn), in which the alkyl spacer length (CH2)n was varied as n = 2, 3, 5, and 6. Photoirradiation of the PA3/BMAB film with a 366 nm light caused trans→cis isomerization of BMAB, which induced simultaneously the nematic (N)→isotropic phase transition of the PLC films. This photochemically induced phase transition was reversible and photoirradiation with a 525 nm light which induced cis→trans isomerization restored the system to the initial phase (N). The photo-induced phase transition was found to be strongly dependent on molecular weight of the host PLC and temperature.

This publication has 4 references indexed in Scilit: