Gas transfer in supported Langmuir-Blodgett films of polymeric lipids

• Tipo: Artigo em Revista Científica Internacional
• Data: 1989

Autores

Stroeve, P (Autor) Outra; coelho, man (Autor) FEUP; Dong, S (Autor) Outra; Lam, P (Autor) Outra; Coleman, LB (Autor) Outra; Fiske, TG (Autor) Outra; Ringsdorf, H (Autor) Outra; Schneider, J (Autor) Outra

Revista

Título: Thin Solid Films

Vol. 180

Páginas: 241-248

ISSN: 0040-6090

Editora: Elsevier

Indexação

Scopus - 7 Citações

Outras Informações

ID Authenticus: P-008-P4S

Abstract (EN): Asymmetric membranes were fabricated by depositing Langmuir-Blodgett (LB) films of polymeric lipids on porous supports. Three polymeric lipids were used for deposition. Up to 50 Y-type layers were deposited on one side of the porous supports of polypropylene (Celgard) and polytetrafluoroethylene (GORE-TEX) membranes. A marked decrease in gas transfer with increasing number of LB layers was observed for the asymmetric membranes fabricated with the porous polypropylene. Gas transfer in the asymmetric membranes using porous polytetrafluoroethylene remained unchanged with the number of polymeric layers. The LB multilayers on polypropylene showed no evidence for pores or cracks as determined by scanning electron microscopy (at a magnification of 40 000x), but the LB multilayers on polytetrafluoroethylene revealed large cracks. The gas permeabilities of nitrogen, methane and carbon dioxide in the polypropylene-based asymmetric membranes were a function of the molecular weight of the gas for two of the three polymers which suggests that micropores are present in the LB films. Heat annealing decreased the gas permeabilities from 0% to 40%, but only one polymer showed a change in selectivity. © 1989.

Idioma: Inglês

Tipo (Avaliação Docente): Científica