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Polyvinylcarbazole (PVK) is a temperature-resistant [2] thermoplastic polymer produced by radical polymerization from the monomer N-vinylcarbazole. It is a photoconductive polymer and thus the basis for photorefractive polymers and organic light-emitting diodes .
Upon exposure to γ-irradiation, N-vinylcarbazole undergoes solid-state polymerisation. [ 5 ] It is produced by the vinylation of carbazole with acetylene in the presence of base.
Living cationic polymerization is a living polymerization technique involving cationic propagating species. [1] [2] It enables the synthesis of very well defined polymers (low molar mass distribution) and of polymers with unusual architecture such as star polymers and block copolymers and living cationic polymerization is therefore as such of commercial and academic interest.
Monomers for living cationic polymerization are electron-rich alkenes such as vinyl ethers, isobutylene, styrene, and N-vinylcarbazole. The initiators are binary systems consisting of an electrophile and a Lewis acid. The method was developed around 1980 with contributions from Higashimura, Sawamoto and Kennedy.
Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). [1] It is one of many forms of luminescence (light emission) and is initiated by photoexcitation (i.e. photons that excite electrons to a higher energy level in an atom), hence the prefix photo- . [ 2 ]
Photoluminescence excitation (abbreviated PLE) is a specific type of photoluminescence and concerns the interaction between electromagnetic radiation and matter.It is used in spectroscopic measurements where the frequency of the excitation light is varied, and the luminescence is monitored at the typical emission frequency of the material being studied.
Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluorescence, a phosphorescent material does not immediately reemit the radiation it absorbs.
The fluorene molecule is most commonly linked at the 2 and 7 positions in polyfluorene derivatives. Also, the 9 position is typically where side chains are attached. This is the photoluminescence of two very similarly structured polyfluorene derivatives.