TY - JOUR
T1 - Surface characterization of copper substrates modified with carboxyl terminated phosphonic acids
AU - Nothdurft, Philipp
AU - Feldbacher, Sonja
AU - Jakopic, Georg
AU - Mühlbacher, Inge
AU - Pötz, Sandra
AU - Kern, Wolfgang
PY - 2018/8/1
Y1 - 2018/8/1
N2 - The surface modification of copper substrates by means of liquid phase reaction with 1H, 1H, 2H, 2H-perfluorooctanephosphonic acid, 6-phosphonohexanoic acid and 16-phosphonohexadecanoic acid is investigated. The substrate preparation is based on common industrial methods and avoids a separate oxidation step of the copper surface prior to modification. Analysis and characterization of the surfaces were performed using various physico-chemical methods. The film formation of a fluoroalkyl phosphonic acid and two carboxyl terminated phosphonic acids on the copper surface was proven by X-ray photoelectron spectroscopy, infrared spectroscopy, SEM/EDX as well as water contact angle measurements. For 16-phosphonohexadecanoic acid a higher film thickness was obtained compared to 6-phosphonohexanoic acid. Hydrogen bonds between adjacent carboxylic terminated phosphonic acids lead to multilayer formation. In additional experiments, these phosphonic acids were investigated as adhesion promoters in copper / epoxy resin laminates in order to replace conventional surface roughening processes. For these laminates, the peel strength was significantly higher when the copper surface was functionalized with 16-phosphonohexadecanoic acid.
AB - The surface modification of copper substrates by means of liquid phase reaction with 1H, 1H, 2H, 2H-perfluorooctanephosphonic acid, 6-phosphonohexanoic acid and 16-phosphonohexadecanoic acid is investigated. The substrate preparation is based on common industrial methods and avoids a separate oxidation step of the copper surface prior to modification. Analysis and characterization of the surfaces were performed using various physico-chemical methods. The film formation of a fluoroalkyl phosphonic acid and two carboxyl terminated phosphonic acids on the copper surface was proven by X-ray photoelectron spectroscopy, infrared spectroscopy, SEM/EDX as well as water contact angle measurements. For 16-phosphonohexadecanoic acid a higher film thickness was obtained compared to 6-phosphonohexanoic acid. Hydrogen bonds between adjacent carboxylic terminated phosphonic acids lead to multilayer formation. In additional experiments, these phosphonic acids were investigated as adhesion promoters in copper / epoxy resin laminates in order to replace conventional surface roughening processes. For these laminates, the peel strength was significantly higher when the copper surface was functionalized with 16-phosphonohexadecanoic acid.
KW - Adhesive strength
KW - Copper
KW - Phosphonates
KW - Surface functionalization
UR - http://www.scopus.com/inward/record.url?scp=85044149459&partnerID=8YFLogxK
U2 - 10.1016/j.ijadhadh.2018.03.012
DO - 10.1016/j.ijadhadh.2018.03.012
M3 - Article
AN - SCOPUS:85044149459
SN - 0143-7496
VL - 84
SP - 143
EP - 152
JO - International Journal of Adhesion and Adhesives
JF - International Journal of Adhesion and Adhesives
ER -