Synthesis and properties of conjugated cyclopolymers bearing fluorene derivatives

Abstract

Fluorene-containing, spiro-type, conjugated polymers were synthesized via the cyclopolymerization of dipropargylfluorenes (2-substituted, X=H, Br, Ac, NO 2 ) with various transition metal catalysts. The polymerization of dipropargylfluorenes proceeded well using Mo-based catalysts to give a high polymer yield. The catalytic activities of the Mo-based catalysts were found to be more effective than those of W-based catalysts. The palladium (II) chloride also increased the polymer yield of the polymerization. The polymer structure of poly(dipropargylfluorene)s was characterized by such instrumental methods as NMR ( 1 H-, 13 C-), IR, UV-visible spectroscopies, and elemental analysis as having the conjugated polymer backbone bearing fluorene moieties. The 13 C-NMR spectral data on the quaternary carbon atoms in polymers indicated that the conjugated cyclopolymers have the six-membered rings majorly. The poly(dipropargylfluorene) derivatives were completely soluble in halogenated and aromatic hydrocarbons such as methylene chloride, chloroform, benzene, toluene, and chlorobenzene. The poly(dipropargylfluorene) derivatives were thermally more stable than poly(dipropargylfluorene) itself, and X-ray diffraction analyses revealed that the polymers are mostly amorphous. The photoluminescence peaks of the polymers were observed at about 457-491 nm, depending on the substituents of fluorene moieties.

Polyfluorene Thin Films Synthesized by a Novel Plasma Polymerization Method

“…Since the observed peak at 2h, 22.9 is too broad and the ratio of the half-height width to diffraction angle (D2h/2h) is greater than 0.35, the PF thin films are mostly amorphous. [33]. In the semi-conducting amorphous solids, where no long-range order exists, only direct optical transitions are meaningful which is consistent with the results obtained from the UV-vis spectra.…”

Electro-optical and electrochemical properties of an conjugated cyclopolymer: Poly(9,9-dipropargylfluorene)

“…We have studied the polymerization behaviors for the cyclopolymerization of dipropargylfluorenes by W-and Mobased catalysts [23,24]. In some cases, the resulting polymers were insoluble at any organic solvents because of the crosslinking reaction during the polymerization.…”

Synthesis, Photophysical Studies of Blue‐Light‐Emitting Alternating Polymers from Substituted 9‐Sila Fluorenes and Substituted p‐Phenylacene

“…This band gap shown by such polymers perfectly match with the band gap of the inorganic semiconductors. The undoped conjugated polymers exhibit the electronic, optical properties of general polymers …”