Effects of montmorillonite interlayer micro-circumstance on the PP melting intercalation

1-Octadecyl-3-methylimidazolium chloride ([C₁₈ mim]Cl) is a kind of imidazolium ionic liquid with high thermal stability. [C₁₈ mim]Cl was used to modify pristine Na-montmorillonite and a series of organo-montmorillonite (OMMT) with different loading levels of 1-octadecyl-3-methylimidazolium cation ([C₁₈ mim]⁺) were obtained. X-ray diffraction (XRD) and thermogravimetric analysis (TGA) results show that there are different loading levels and aggregative state of [C₁₈ mim]⁺ in the interlayer of OMMT. The effects of OMMT interlayer micro-circumstances on the PP melting intercalation were studied by XRD and transmission electron microscopy (TEM). Results indicate that the melting intercalation of PP into the interlayer of OMMT is not only related with d-spaces but also has something to do with the interlayer micro-circumstance of OMMT. Based on these facts, three types of interlayer absorption models of [C₁₈ mim]⁺ in the interlayer of OMMT were conceived. In addition, the aggregative state of [C₁₈ min]⁺ in the interlayer of OMMT, interlayer polarity and d-spaces of OMMT were discussed. According to these models, we try to illustrate the effect of interlayer micro-circumstance of OMMT on the PP melting intercalation.