Nanocomposites present interesting mechanical properties owing to the high surface-area-to-volume ratio of the dispersed reinforcement. The vibration weldability of these new composites has not yet been reported in the literature. This research examines the effect of the vibration-welding parameters of weld pressure and target meltdown on the strength of butt welds made from two polypropylene-based nanocomposites. The nanocomposites were made by melt-compounding two levels of organoclay with polypropylene. The results of unreinforced polypropylene are shown for reference. All welded assemblies were assessed by tensile testing. The results show that 3-6% of organoclay reinforcement causes a significant decrease in weld strength.

A newly designed and constructed sliding plate rheometer is used to measure the high frequency (210 Hz) linear viscoelastic properties of two model polymers: polybutene (PB) and polydimethylsiloxane (PDMS). Using well-known rheological models, extrapolations of the viscoelastic measurements obtained on a rotational parallel plate rheometer to a frequency of 210 Hz are used to assess the performance of the high frequency sliding plate rheometer. Good agreement between the extrapolated and measured data demonstrates the ability of the sliding plate rheometer to measure the high frequency rheological properties of both Newtonian and shear-thinning materials.