Thiacalix[4]arene compound as nucleating agent of β crystals in polypropylene/MMT composites

In this study, thiacalix[4]arene compound is used as a nucleating agent for the hexagonal phase of polypropylene/montmorillonite composites. Its morphology, thermal and optical properties are studied as a function of their contents. This study is the first stage towards thorough understanding of the behavior of these composites. The addition of thiacalix[4]arene compound to polypropylene/montmorillonite composites excites the generation of β phase crystals. Along with maleic anhydride, it generates an 'intercalation-like' phase where the characteristic peaks of montmorillonite almost vanish. The thermal behavior confirms the existence of β crystals and suggests the presence of two types of phase transformations (α ⇌ β) based on the contents of the composites. The intensity of C–H stretching vibrational energy of β crystals changes for the hexagonal phase. PL results reveal the expansion of the optical band gap energy with a rich environment of excitons.