Title of article :
Microstructure, topology and X-ray diffraction in
Ag-metal reinforced polymer of polyvinyl alcohol
of thin laminates
Author/Authors :
A. Gautam، نويسنده , , P. TRIPATHY، نويسنده , , S. RAM?، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2006
Abstract :
A polymer composite of Ag-metal reinforced polyvinyl alcohol (PVA) is synthesized in shape of
thin laminates of 200–300 μm thickness. The process involves a chemical Ag+ dispersion in PVA
and in-situ Ag+ → Ag reduction-reaction with active PVA molecules under hot conditions (with
stirring) in water at 60–70◦C temperature. The product results in a metal Ag-polymer complex
dispersed in the solution. After evaporating part of water, a derived viscous solution is casted
(in hot conditions) in shape of a thin laminate in a glass mould. In addition to chemical reducer,
active OH-groups (free from H-bonding) in PVA molecules of refreshed surfaces act as head
groups to adsorb Ag+ and drive a directional Ag+ → Ag growth. Short fibrils of Ag-metal thus
occur in reaction over the PVA molecules. Casting thin laminates from a liquid sample Ag-PVA
allows the fibrils (also the polymer molecules) to align along the surface. Selected Ag-contents
up to 5.0 wt.% in Ag-PVA laminates are studied in terms of scanning electron micrograph, X-ray
photoelectron spectroscopy (XPS) and X-ray diffraction. Average size, morphology and aspect
ratio (ϕ) vary in Ag-metal depending on the Ag-content. As long Ag-metal fibrils as 2–5 μm,
ϕ =35, occur in a sample of 2.0 wt.% Ag. The Ag-metal reflects in two characteristic 3d5/2 and
3d/3/2 XPS bands of 368.3 and 374.1 eV respectively.
C
2006 Springer Science + Business Media, Inc.
Journal title :
Journal of Materials Science
Journal title :
Journal of Materials Science