Data/hora: 15/06/2024 13:50:52

Biblioteca(s): | Embrapa Instrumentação.
Data corrente: | 22/12/1999
Data da última atualização: | 22/12/1999
Autoria: | MATTOSO, L. H. C.; PATERNO, L. G.; CAMPANA, S. P.; OLIVEIRA JUNIOR, O. N.
Afiliação: | EMBRAPA-CNPDIA; USP-IQSC; USP-IFSC.
Título: | Effect of pH on the adsorption kinetics of self-assembled films from doped poly(o-ethoxyaniline).
Ano de publicação: | 1996
Fonte/Imprenta: | In: INTERNATIONAL CONFERENCE ON SCIENCE AND TECHNOLOGY OF SYNTHETIC METALS, July-Aug. 1996, Snowbird, UT, Estados Unidos. Abstracts... Snowbird: Utah University, 1996.
Páginas: | p.356.
Idioma: | Inglês
Notas: | Ref.P3.102.
Conteúdo: | The adsorption process of alternated, yltra-thin films of carboxymethylcellulose and HCI-doped poly(o-ethoxyaniline) onto glass substrates by the self-assembly technique was studied by ultraviolet-visible spectroscopy. The kinetics of adsorption for the 1st, 2nd, 5th and 10th bilayers obeys a first order process for a polymer concentration of 10E-3 M, with characteristic times in the order of 100s, independently of the solution pH in the range 1 to 5. This result is in contrast with data obtained for higher polymer concentrations where adsorption comprised two stages: a fast, first order kinetics process (characteristic time of only 5s) followed by a much slower process. It was also observed that adsorption is faster and more effective for pH=1. This probably occurs because at lower pHs the polymer is more strongly doped which promotes an increase in the electrostatic attraction of the polymeric molecules to the substrate.
Categoria do assunto: | --
Registro original: | Embrapa Instrumentação (CNPDIA)
Exemplares: | CNPDIA - (5626-1) - UPC - PL - -- - PROCI -  - 1996. - DIS