Abstract
A series of photoconducting poly(tetraphenyldiaminobiphenylene alkyl ether)s in which tetraphenyldiaminobiphenyl (TPD) units are covalently linked through flexible oligomethylene glycol spacers in the main chain were synthesized and the thermal, optical and electrochemical properties were studied. Due to the introduction of flexible spacers, the polymers are highly soluble and could be obtained as film-forming materials with appreciably high molecular weights. The polymers exhibit glass transition temperatures between 92 °C and 128 °C which is about 100 °C less than those main chain polymeric bis(triphenylamine)s without such spacers. The HOMO value as determined from cyclic voltammetry is about −5.1 eV. The glass transition temperature of the photorefractive composites prepared by mixing the different polymers with an electro-optic chromophore, 1-(2-ethylhexyloxy)-2,5-dimethyl-4-(4-nitrophenylazo)benzene, EHDNPB, could be tuned over a wide range about room temperature by just changing the photoconductor and without the need of any additional amount of plasticizer. Degenerate four-wave mixing and two-beam coupling in composites with the composition, photoconductor ∶ EHDNPB ∶ C60 (60 ∶ 39 ∶ 1 by wt/wt%) results in refractive index modulations of 10−3 with corresponding response time ∼10 ms and a photorefractive gain of Γ = 13 cm−1 for a writing beam intensity of 1 W cm−2 (645 nm) under an external electric field of 60 V µm−1.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.