Dielectric spectroscopy and molecular dynamics of epoxy oligomers with covalently bonded nonlinear optical chromophores

FTIR investigation of molecular mobility in glassy epoxy-amine oligomers with azo-chromophores

“…Since at T f ~ -90°C the local mobility of the probe with smaller activation volume terminates, this gives evidence to the lack of the free volume in the oligomer. This statement is in agreement with the conclusion made in [10] on the basis of molecular simulation study, that relaxation β-process in CFAO is related to the freezing of the benzene rings motion.…”

“…It can be seen that the conformational mobility of DCE and CCH is freezing-in at the similar temperature, around T f = -90°С. According to [10] β-process in CFAO takes place in this temperature range.…”

Investigation of Azo Polymers Local Mobility by Oscillatory Spectra of Chromophores

“…Inflection of plots is close to 60 °C. The received temperature within the errors matches temperature β 1 of relaxation transition found in the paper [14] by means of dielectric spectroscopy. The authors connect this relaxation transition with the emergence of biphenol fragments mobility with adjacent ether groups and OCCO fragments of the main chain.…”

“…Точка перегиба графиков находится вблизи 60°С. Полученная температура в пределах ошибок совпадает с тем-пературой β 1 релаксационного перехода, обнару-женного в работе [14] методом диэлектрической спектроскопии. Этот релаксационный переход авторы связывают с появлением подвижности бисфенольных фрагментов со смежными эфир-ными группами и фрагментов OCCO основной цепи.…”

Determination of the Glass Transition Temperature of Freestanding and Supported Azo-Polymer Thin Films by Thermal Assisted Atomic Force Microscopy

“…Due to trans-to-cis photoisomerization, azochromophores found applications in formation of surface relief gratings and study of nonlinear optical effects. [1][2][3][4] These effects are widely used in practice, for example for optical switching and storage, [5][6] light filtering 7-10 and frequency conversion. 11 In particular, bottlenecks of optical near-field memory based on azo-polymers are cycling endurance, data retention, and thermal stability.…”