TIT# Functionalization of Multi-Walled Carbon Nanotubes (MWCNT's) with Pimelic Acid Molecule: Effect of linkage to induce á-crystal in an Isotactic Polypropylene matrix (iPP). AUT# Gonzalez Calderon, J. A.; Castrejon Gonzalez, E. O; Medellin Rodriguez, F. J.; Stribeck, Norbert; Almendarez Camarillo, Armando; SOU# J. Mater. Sci. (2015), 50(3), 1457-1468 LOC# xv151 CLA# COM# APP# MAT# ABS# An alternate method to functionalize MWCNT's with pimelic acid molecule (PA) with ionic bridging linkage is proposed. This bridged linkage increases the amount of á-crystal in iPP matrix compared to chelating linkage of the same molecule. Evidence of a lateral bridge between PA and the MWCNT's was obtained from the infrared spectra of the functionalized carbon nanotubes (MWCNT-f). This fact was confirmed by the absence of a characteristic infrared band at 1540 cm-1 which is attributed to a chelating form of the PA known as calcium pimelate (MWCNT-PS). Furthermore, an increase on the thermal stability of the attached PA due to ionic linkage was found by differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA). iPP nanocomposites were prepared with these MWCNT-f, finding an improvement on the induction of á phase in the nanocomposites by DSC and wide angle X-ray diffraction (WAXD) analysis. In addition, the evolution of the crystallization activation energy for the resulting nanocomposites was investigated. We correlate the energy requirements of the interaction between nucleating agents and the segments of iPP. It was found that the bridged form of the molecule is associated with an increased energy barrier during the crystallization process, this because of á-crystal is thermodynamically unstable and the amount induced is higher than promoted by chelated form. In this article, we demonstrate how the type of linkage between MWCNT's and PA could have a strong influence on the ability of this organic molecule to nucleate á-crystal and on the crystallization behavior in iPP nanocomposites.