Chemisorption mechanism and effect of polyacrylic acid on the improvement in bond durability of zinc phosphate-to-polymer adhesive joints

Technical Report · Wed Jan 01 04:00:00 EST 1986

OSTI ID:5820179

Sugama, T; Kukacka, L E; Carciello, N; Warren, J B

It has been found that the outermost surface sites of polyacrylic acid-complexed crystalline Zn x Ph layers precipitated on cold-rolled steel surfaces act significantly to promote interfacial adhesive bonding to polymeric topcoats. This is the result of electrostatic internal diffusion and segmental chemisorption mechanisms of polyelectrolyte macromolecules either on newly precipitated crystal nuclei or on crystal growth sites during the primary zinc phosphate (Zn x Ph) conversion process. The nature of the polymer-to-polymer chemical bond produced at the polymer-to-complex Zn x Ph precoat interfacial joints plays the key role in the achievement of long-term bond durability upon exposure to chemically corrosive environments. The locus of adhesive loss at the polymer-to-complex Zn x Ph joints after exposure to a hot acid solution was clearly identified to be cohesive failure in the crystalline precoat layers. A stable bond resulted from the formation of an interfacially produced hydrophobic structure by interactions between the polymer and the functional organic species existing on the complex precoat surfaces. The chemisorbed polyelectrolytes also served to chemically couple the organic coating and the inorganic Zn x Ph conversion layer.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5820179
• Report Number(s): BNL-37808; ON: DE86011535
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ADHESION
BONDING
CHEMICAL REACTIONS
CHEMISORPTION
ELECTRON SPECTROSCOPY
ESTERS
FABRICATION
JOINING
JOINTS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
POLYACRYLATES
POLYMERS
POLYVINYLS
SEPARATION PROCESSES
SORPTION
SPECTROSCOPY
ZINC COMPOUNDS
ZINC PHOSPHATES