Solvent-dependent morphology of TMB-5 nucleating agent and the effects on the inducing efficiency of β-iPP crystal

TMB-5, an aryl amide-based compound, was treated with various solvents and employed as a beta-nucleating agent (beta- NA) to tailor the structure and properties of iPP. The crystalline structures and morphological evolution of different iPP/TMB-5 specimens were investigated via wide-angle X-ray diffraction (WAXD) and the Olympus BX51 optical microscope equipped with the Linkam CSS-450 hot stage, respectively. The results indicated that reducing the polarity of the solvent employed in the treatment of TMB-5 was conducive to deceasing the particle size and increasing the specific surface area of the initial TMB-5 particles. It facilitated the formation of needle-like/shish-like self-assembled TMB-5 in iPP melt, and promoted the formation of beta-iPP crystal. These findings provide an alternative approach for tailoring the beta-crystal inducing efficiency of TMB-5, which can modulate the beta-crystal content and thus enhance the performance of iPP products. A proposed mechanism for the crystallization of beta-iPP induced by NA is presented, taking into account the influence of solvent-dependent NA morphology.