Structure and Properties of Polymers and Organosilanes Adsorbed Onto Oxidized Aluminum and Titanium.
Abstract
The structure of films formed by organofunctional silanes adsorbed onto aluminum, titanium, and iron mirrors from aqueous solutions was related to the effectiveness of the silanes as primers for improving the wet strength of metal-to-metal adhesive joints made from the same metals. Gamma-aminopropyltrieth-oxysilane (gamma-APS) formed smooth, continuous polysiloxane films when adsorbed onto iron from aqueous solutions at pH 8.0. Such films were extremely effective primers. Lap joints prepared from iron adherends primed with gamma-APS at pH 8.0 retained about 70% of their original strength after 60 days immersion in water at 60C while joints prepared from unprimed adherends retained only 25% of their strength. Gamma-APS was less effective when applied to iron adherends at pH 10.4 but lap joints prepared from such adherends still retained 50% of their strength after 60 days in water at 60C. Gamma-glycidoxypropyltrimethoxysilane (Gamma-GPS) formed polysiloxane films that were effective primers when adsorbed onto iron from aqueous solutions containing an acid to catalyze hydrolysis of the silane. The environmental failure of iron/epoxy lap joints was consistent with a model suggesting debonding of the adhesive a certain distance into the joint when a critical concentration of water was obtained that same distance into the joint.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1981
- Accession Number
- ADA102365
Entities
People
- F. James Boerio
Organizations
- University of Cincinnati