Structural analysis of Fibres spun from Compounded Nanocomposite of Aluminium Silicate Hydroxide/Polyolefin

Abstract

Nanocomposites fibers of different polypropylene (PP), a polyolefin type - Aluminum Silicate Hydroxide (Kaolinite) were prepared by melt compounding using a two-step process: melt-spinning and hot drawing at various draw ratios. The drawn fibres were characterized for their microstructure using X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), and Thermogravimetric Analysis and the resuls are presented in this paper. TEM and FESEM revealed good dispersion of the kaolinite nanoparticles in polypropylene matrix, although at higher concentrations and lower draw ratios the nanoparticles showed increasing tendency to form small agglomerates. Drawing of K30-HP-30B and K20-ATO nanocomposite is difficult due to large agglomerates formations. In as-spun fibers only one β-relaxation peak can be observed while two peaks of and occurs for drawn fibers in DMA analysis. XRD also reveals a strong orientation of kaolinite along the chain axis after drawing of nanocomposite. There is a significant change in crystallinity transform of the -phase structure into a γ-phase. Even though TEM micrographs of K20-HP shows overcrowded kaolinite particles it is possible to observe improvement of kaolinite dispersion with drawing process.