The Orientation Stability and UV Irradiation of Poly(hexa‐2,4‐diynilene‐1,6‐dioxy)benzoates and Cinnamates ContainingDisperse Red 19

Abstract

The poling and orientation parameters of the four polymers para and meta benzoates and cinnamates containing Disperse Red 19 dye were studied. The para polymers were found to be orientated more efficiently, and their stabilities were much better than the meta polymers. The photobleaching takes place when irradiated at temperatures around Tg, but did not occur when irradiated under the poling conditions. After the photo cross-linking at around Tg the orientation maintenance of the para polymers were found to be almost indefinite. The stability of the para polymers is considered to be due to their stable main chain conformation when poled.

SECOND-ORDER NONLINEAR OPTICAL SUSCEPTIBILITIES OF POLY[(HEXA-2,4-DIYNYLENE-1,6-DIOXY)DIBENZOATES] CONTAINING AZO CHROMOPHORE DISPERSE RED 19 BY ELECTROABSORPTION SPECTROSCOPY

“…It is known that the meta-polymer undergoes relaxation more quickly than the para-polymers. 3 Therefore, the orientation parameter of the meta-polymer may be lower than that of the para-polymer at the moment of EAS measurements. Figure 3 depicts the spectra of absorption coefficient change (∆α) for each polymer.…”

“…Furthermore, these polymers can be cross-linked by UV irradiation at the poling temperatures through their diacetylene groups, so that the films are converted into totally hard thermoset polymers in which the motion of chromophores is restricted. Especially, the para-cinnamate polymers showed indefinite stability at 80 • C. 3 The value of second-order NLO coefficients depends on the measurement methods and conditions, and therefore, it is of interest to determine the coefficients by a different method, in order to see if the results coincide with each other. The electroabsorption spectroscopy (EAS) is a useful tool to investigate thirdorder NLO properties of organic materials.…”

Preparation and morphological and optical characterization of azo-polymer-based SiO2sonogel hybrid composites

“…, where 0 1, A 1 (λ MAX ) and A 2 (λ MAX ) are the sample absorption before and after electrical poling at λ MAX , respectively. Table 4 summarizes the parameters evaluated for the studied samples; due to the low T g values of the available implemented polymers (see table 1), these parameters are rather low compared to other azo-polymer poled films [28,30]. As for deposition parameters, the relation between microstructure, NLO and optoelectronic properties of the obtained films needs to be further understood and clarified since the magnitude of the parameters does not correspond to the T g values, indicating the doping and poling procedure in our sonogel process is still ineffective and needs to be further improved.…”

Synthesis, Characterization and Some Optical Properties of Poly(hexa-2,4-diynylene-1,6-dioxy)dinaphthoates Containing Polar Azo Dye

“…For example, the para-polymers shown in Scheme 1 showed much higher 2-NLO susceptibilities [7,8] and orientation stability [9] than the corresponding meta-polymers. Thus the main-chain conformation has a strong influence on the orientation and its stability of chromophores by corona poling.…”