Surface Functionalized Polypropylene: Synthesis, Characterization, and Adhesion Properties Academic Article uri icon

abstract

  • Modification of polypropylene by hyperbranched grafting with a poly(acrylic acid) graft was carried out using techniques previously used with gold, aluminum, silicon, and polyethylene surfaces. An initial etching oxidation produced a modifed polypropylene that was presumed to contain carboxylic acid functional groups (though none were detected by IR spectroscopy). Then, a series of repetitive grafting experiments using an α,ω-diamine derivative of poly(tert-butyl acrylate) were used to produce surfaces containing significant amounts of poly(acrylic acid). The resulting surfaces were characterized by ATRIR spectroscopy, contact angle measurements, and XPS spectroscopy. Treatment of the surfaces with alkali produced a more hydrophilie carboxylate surface. Treatment of these surfaces first with ethyl chloroformate followed by pentadecylfluorooctylamine produced a hydrophobic fluorinated surface. Mechanical tests show that such surface modification not only serves as a route to modify polypropylene's hydrophilicity/hydrophobicity-such modification substantially affects the adhesive strength between this modified polypropylene and an epoxy adhesive. Double cantilever beam tests show that adhesion increases from 2 J/m 2 for unmodified polypropylene to up to 29 J/m 2 with the modified polypropylene.

author list (cited authors)

  • Tao, G., Gong, A., Lu, J., Sue, H., & Bergbreiter, D. E.

publication date

  • January 1, 2001 11:11 AM