Voltar
Artigo Acesso aberto Produção Nacional Revisado por pares
BIBTEX RIS

Aquisição de tempos de vida de fosforescência com resolução de fase e sua aplicação ao estudo de relaxações em polímeros

1998; Brazilian Chemical Society; Volume: 21; Issue: 3 Linguagem: Inglês

10.1590/s0100-40421998000300015

ISSN

1678-7064

Autores

Márcio Talhavini, T. D. Z. Atvars,

Tópico(s)

Polymer crystallization and properties

Resumo

PHASE RESOLU-TION METHOD.We describe in this work a simple experimental set up to perform time dependent luminescence experiments in time scales from mili-seconds to seconds, based on the phase resolution of the emission signal.This system is composed by modulation of a continuous light source with an external chopper controlled by a lock-in amplifier.We exemplified the utility of the system in studies of phosphorecence emission using benzophenone dissolved in polystyrene and since the phosphorescence intensity and lifetime are temperature-dependent processes, we also studied polymer relaxation processes in the temperature range from 20 to 400K.A software that drives the spectrofluorimeter and controls both the cryosystem and the lock-in amplifier was developed.

Referência(s)