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In our work, zinc hexahydrophthalate (HHPA-Zn) was synthesized and its β-nucleating activity in isotactic polypropylene (iPP) was confirmed. The single crystals of HHPA-Zn were obtained for the first time, with the crystal structure analyzed. The results of differential scanning calorimeter (DSC) and wide-angle X-ray scattering (WAXS) showed that HHPA-Zn increased the crystallization temperature of iPP by 11.2 °C and induced considerable amount of β-crystalline iPP (β-iPP) with the K β up to 0.66. The investigations of the mechanical performance of iPP showed an increase of 193% in the impact strength with the help of HHPA-Zn. Based on the crystal structure data and the lattice matching theory, the structural matching mechanism of HHPA-Zn and iPP was proposed, and the crystallization process of iPP induced by single crystals of HHPA-Zn was observed by polarized light microscope (PLM) to support the epitaxial crystallization of β-iPP. Flash differential scanning calorimeter (Flash DSC) was conducted to explain the formation of a bit α-crystalline in crystallization.

How to improve the mechanical and thermodynamic properties is still a big challenge for transition metal borides. Alloying method is a good route based on the valence electronic discrepancy. However, the mechanism of alloying addition is unknown. In this article, the influence of alloying elements (TM = Mo, W, Os, and Re) on the structural stability, elastic properties, hardness, and thermodynamic properties of Ru2B3 is studied by first-principles approach. Phonon dispersion, elastic properties, hardness, electronic structure, Debye temperature, and heat capacity of Ru2B3 with alloying elements are calculated. It is found that Ru2B3 with alloying elements are thermodynamic stability and dynamic stability at the ground state. We predicted that the alloying elements can improve the elastic properties and hardness for Ru2B3. Owing to the high valence electronic density, the shear deformation resistance of Ru2B3 with alloying elements of Re and W is up to 12.7% and 11.1% in comparison with the perfect Ru2B3. We suggested that heavy alloying elements can result in charge transfer from TM atom to B atom and forms the strong B–B covalent bond. Finally, we concluded that alloying can improve the Debye temperature for Ru2B3.