TSC and Broadband Dielectric Spectroscopy Studies of the α Relaxation in Phosphorus-Containing Dendrimers

Eric Dantras (1) , Jany Dandurand (1) , Colette Lacabanne (1) , Anne-Marie Caminade (2) , Jean Pierre Majoral (2)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 LCC - Laboratoire de chimie de coordination

The aim of this work is to analyze the dielectric manifestation of the glass transition (R mode) of amorphous dendritic macromolecules as a function of architectural complexity. A set of phosphorus-containing dendrimers involving six generations (g ) 0-5) has been investigated by thermostimulated currents and broadband dielectric spectroscopy. The dielectric complex permittivity has been obtained as a function of temperature, in a broad frequency range (10-4-106 Hz). For frequencies higher than 1 Hz, the dendrimers show a high temperature R mode with a Vogel-Tamman-Fulcher type temperature dependence. For frequencies lower than 1 Hz, the R mode takes place in the vitreous state; it has been associated with a series of thermally activated cooperative movements free from generation influence. Dielectric and thermal properties are discussed as regards of fractal architecture and chemical modification of end groups.

Mots clés: TSC; Broadband Dielectric; Spectroscopy Studieso; Phosphorus-Containing

Domaines: Chimie de coordination

Eric Dantras, Jany Dandurand, Colette Lacabanne, Anne-Marie Caminade, Jean Pierre Majoral. TSC and Broadband Dielectric Spectroscopy Studies of the α Relaxation in Phosphorus-Containing Dendrimers. Macromolecules, 2004, vol. 37 (n° 8), pp. 2812-2816. ⟨10.1021/ma049955i⟩. ⟨hal-01308058⟩