Structure and Properties of Polymer Interphases.
Abstract
Infrared spectroscopy was used to determine the effect that metal substrates such as titanium, steel, 1100-series aluminum, 2024 aluminum, and copper have on the molecular structure and properties of gamma-aminopropyltriethoxysilane (gamma-APS) primer films. When gamma-APS was absorbed onto any of the substrates from aqueous solutions at pH 10.4 for one minute and then dried at room temperature for thirty minutes, the molecular structure of the primer films was similar and consisted of low molecular weight siloxane polymers containing an considerable amount of absorbed carbon dioxide in the form of amine bicarbonates. When drying was carried out at 110 C, films formed on titanium, steel, and 1100-series aluminum were similar. The extent of polymerization in the films increased and most of the bicarbonates were dissociated. However, the amino groups in films formed on 2024 aluminum and copper oxidized to imine groups and the polymerization did not increase significantly. After drying at 150 C, the films formed on titanium, steel, and 2024 aluminum were all oxidized to the imine but the oxide on 1100-series aluminum inhibited the free radical oxidation reaction. Dissociation of the bicarbonates and oxidation of the amino groups were important factors in the reaction of the primers with epoxy resins.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1987
- Accession Number
- ADA183559
Entities
People
- F. James Boerio
Organizations
- University of Cincinnati