S.S. Vaezzadeh, R.K. Bradley
Keywords: thermoplastic, composite, nanoparticle, nanomaterial, creep, corrosion, pipe support, compounding
Summary:Thermoplastics undergoing long-term static load can suffer permanent deformation and eventual fracture due to creep. We are particularly interested in thermoplastic pipe-support pads designed to minimize water entrapment and the associated corrosion at the contact point. By employing a “road bump” shaped cross-section, moisture entrapment is minimized but the load from the pipe is concentrated onto a small surface area making creep a more significant problem. Deformation of the “road bump” will diminish the functionality of the pad, so a creep-resistant material is needed. We will discuss the results of our investigation into creep-resistant thermoplastics nanocomposites. Thermoplastics were chosen because non-conducting pads prevent galvanic and stray current corrosion, but they were also chosen due to their low cost of production, and we seek a nanomaterial filler that can improve creep resistance while maintaining the low overall cost. We utilize a blade-style mixer to compound small quantities of thermoplastic and filler in order to provide a high degree of control over compounding parameters. Characterization of nanoparticle filler dispersion via electron microscopy and dielectric spectroscopy will be covered as well as the results of short-term and long-term mechanical testing of samples. Implications to the specific application of pipe supports will be discussed as well as broader scientific conclusions.