Novel photoactive hyperbranched poly(aryl ether)s containing azobenzene chromophores for optical storage

Abstract

Two novel hyperbranched poly (aryl ether)s with azobenzene moieties in both the main chain and side chain of the branched arms were prepared by using B 3 + A 2 methodology via a nucleophilic aromatic substitution polycondensation. Structures of the hyperbranched poly (aryl ether)s with azobenzene moieties (azo-HPAEs) were characterized by means of IR, UV-visible, 1 H NMR spectroscopy, and XRD. It is shown that both the azo-HPAEs exhibit high glass transition temperatures (T g ), excellent thermal stability and homogeneous photochromic behavior. By exposing their spin-coating films to an interference pattern of laser beam, both the azo-HPAEs could be used for rapid (within 30 s) fabrication of surface-relief gratings (SRGs). The obtained SRGs present no shape changes even at temperatures up to 200 C. Especially, the azo-HPAE with azobenzene moieties in the side chain shows larger photoinduced birefringence intensity and better reversible optical storage than the one with azobenzene moieties in the main chain upon irradiation with 532 nm Nd:YAG laser. The novel azo-PAEs are photoactive to UV light (355 nm), making them potentially useful for high density information storage.

Fabrication of fluorescent holographic micropatterns based on the rare earth complexes using azobenzene-containing poly(aryl ether)s as macromolecular ligands

“…4,4′‐Bis(4‐hydroxyphenyl)valeric acid (BHPVA) was purchased from Alfa Asar. 4,4′‐Dihydroxyphenylazodiphenylsulfone (DHPADS) was synthesized according to the literatures . Rare earth nitrate hexahydrates (Re(NO 3 ) 3 ·6H 2 O, Re 3+ = Eu 3+ and Tb 3+ ) were obtained from Shanghai Diyang Chemical Factory.…”

“…The experimental setups for SRGs formation have been described by our group previously, and only several details were given here. The SRGs were optically inscribed on the spin‐coated films with p‐polarized interfering laser beams.…”

“…The SRGs are stable below the glass transition temperatures ( T g s) of the polymers and can be removed by heating the polymers above their T g s or can be erased optically. Therefore, introducing azobenzene chromophores into some high‐ T g aromatic polymers, such as azo‐PAEs, was helpful to improve the stability of azobenzene chromophores …”

Polyvalent Diazonium Polymers Provide Efficient Protection of Oncolytic Adenovirus Enadenotucirev from Neutralizing Antibodies while Maintaining Biological Activity In Vitro and In Vivo

“…Unexpectedly, the absorbance of EnAd-P8 exceeded the value observed for the uncoated viral control which would indicate an increase in antibody binding. This was attributed to the combined effect of inefficient polymer coating, resulting in significant antibody binding, and the absorbance in the same spectral region as the ELISA substrate (450 nm) (43) of any azobenzene linkages present.…”

Molecular captain: A light‐sensitive linker molecule in poly(ethylene glycol)‐poly(L‐alanine)‐poly(ethylene glycol) triblock copolymer directs molecular nano‐assembly, conformation, and sol‐gel transition

“…Azobenzene is known to undergo reversible trans‐to‐cis or cis‐to‐trans configurational changes upon exposure to ultraviolet (UV) light or visible (vis) light, respectively. Such a configurational change has been applied for data storage, sensors, optical switching, ultrahydrophobic/ultrahydrophilic surface modification, pulsatile drug delivery, and light‐sensitive mechanical movement 11–16. Changes in self‐assembly of the azobenzene‐containing polymers were achieved by exposure to UV or vis light 17–22.…”