Articolele autorului Valeria Harabagiu
Link la profilul stiintific al lui Valeria Harabagiu

Synthesis, morphology, and thermal behavior of polyrotaxanes

Epoxy-terminated polydimethylsiloxanes of two molecular weights (Mn about 1,250 and 2,100) were proved to undergo inclusion complexation into the inner cavity of c-cyclodextrin, thus resulting in formation of polyrotaxanes. The supramolecular assembling, the structure, the morphology, and the thermal properties of polyrotaxanes were shown to depend on the polymer molecular weight, the molar ratio between the components, and the presence of free gamma-cyclodextrin.

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Synthesis and characterization of a poly [2,7-(9,9-dioctylfluorene-alt-2,7-fluorene/β-CD)] main chain polyrotaxane

Poly[2,7-(9,9-dioctylfluorene-alt-2,7-fluorene/b-CD)] main chain polyrotaxane was synthesized through organometallic Suzuki coupling by reacting b-cyclodextrin/2,7-dibromofluorene inclusion complex with 9,9-dioctylfluorene-2,7-bis(trimethyleneborate). The IR, NMR and elemental analysis data support the presence of b-cyclodextrin in the copolymer structure. No glass transition or melting phenomena were detected in DSC curves of the polyrotaxane on

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Mild and selective oxidation of cellulose fibers in the presence of N-hydroxyphthalimide

The oxidation reaction of regenerated cellulose fibers mediated by N-hydroxyphtalimide (NHPI) and various cocatalysts at room temperature for different time intervals and various amounts of low concentration sodium hypochlorite solution has been investigated to produce oxidized cellulose (OC), a biocompatible and bioresorbable polymer. The results revealed that the non persistent phthalimide-Noxyl (PINO) radical generated in situ from NHPI in both,

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Polyrotaxanes of Pyrene–Triazole Conjugated Azomethine and a-Cyclodextrin with High Fluorescence Properties

The paper reports on the preparation of a new 2-rotaxane monomer through an acid coupling reaction between 1-pyrenecarboxaldehyde and α-CD/3,5-diamino-1,2,4-triazole inclusion complex. Pyrenyl groups are large enough to provide a blocking effect towards cyclodextrin dethreading. The oxidative C-C coupling of the 2-rotaxane in the presence of RuCl3 catalyst afforded conjugated polyrotaxanes. The expected modifications of the solubility, morphology,

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