Dielectric properties of styrene/acrylate copolymer coatings formed by electrophoretic deposition on gold, aluminum alloy, and porous anodized aluminum alloy substrates

Technical Report · Wed Apr 01 04:00:00 EST 1987

OSTI ID:6615212

Panitz, J K.G.; Sharp, D J; Martinez, F E

Styrene/acrylate copolymer coatings were electrophoretically deposited on four types of substrates. Processing characteristics were observed including cell voltage vs time for current densities of 0.05 to 4 mA/cm/sup 2/; polymer coating thickness vs cell voltage; and polymer coating thickness vs Coulombic consumption. Properties of the resultant polymer coatings were evaluated including breakdown voltage vs thickness; capacitance and dielectric constant; composition (from Fourier transform infrared spectroscopy); and morphology (from Scanning Electron Microscopy). Little polymeric coating deposition occurs if the current density is low. Defective coating growth occurs at high current density. The relationship between polymer thickness and cell voltage depends on the type of substrate coated and the current density used. After the initial stages of deposition, coating formation proceeds at a rate of 0.2 ..mu..m/ mA cm/sup -2/ s. Anodization occurs during electrophoretic deposition onto the aluminum alloy and the anodized aluminum alloy substrates; more anodization occurs at lower current densities and at the beginning of electrolysis. The dielectric constants and the intrinsic breakdown strength exhibited by the coatings depend on the coating thickness and on substrate type. The release of water from the coatings during the curing cycle allows coatings exhibiting breakdown a strength as high as 1000 V/..mu..m to form at cell voltages of 4 to 14 V per ..mu..m polymer coating thickness.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6615212
• Report Number(s): SAND-85-2873; ON: DE87008885
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
ALUMINIUM ALLOYS
ANODIZATION
CHEMICAL COATING
COPOLYMERS
CORROSION PROTECTION
CURRENT DENSITY
DEPOSITION
DIELECTRIC PROPERTIES
ELECTRICAL PROPERTIES
ELECTROCHEMICAL COATING
ELECTROLYSIS
ELECTROPHORESIS
ESTERS
LYSIS
MATERIALS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PHYSICAL PROPERTIES
PLASTICS
POLYACRYLATES
POLYMERS
POLYOLEFINS
POLYSTYRENE
POLYVINYLS
SUBSTRATES
SURFACE COATING
SYNTHETIC MATERIALS