Polypropylene fiber-matrix bonds in cementitious composites

It is known that for creating advanced polyolefin/cement-based composites t he polymer surface should be converted into a layer which is compatible wit h the inorganic component. In this respect, plasma chemistry offers additio nal solutions to the wet chemistry approach. It. has been demonstrated duri ng the last decade that cold plasma-mediated reactions are suitable for etc hing and surface functionalizing even the most inert polymeric substrates, including Teflon, polypropylene (PP), and polyethylene (PE), In this paper composite preparations from SiCl4-cold plasma and chromic acid-treated fibr illated PP substrates and cement are described. The nature of plasma- and w et chemistry-induced surface functionalization and etching processes was mo nitored using survey and high-resolution X-ray photoelectron spectroscopy ( XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) sp ectroscopy, atomic force microscopy (AFM), and dynamic water contact angle measurements. It has been demonstrated that the plasma-exposed surfaces res ult in increased adhesion between the fibers and the cementitious matrix in comparison with the chromic acid-modified fibers. It has been shown that t he improved tensile strength values can be related to the treatment-generat ed polar surface functionalities as well as roughness.