Study of PET/PP/TiO 2 microfibrillar‐structured composites, part 1: Preparation, morphology, and dynamic mechanical analysis of fibrillized blends

The objective of this study was to manufacture and investigate a novel microfibrillar‐reinforced material based on fibrillized blends of polyethyleneterephthalate (PET), polypropylene (PP), and TiO 2 nanoparticles (300 nm and 15 nm in size). The uncompatibilized and compatibilized blends (polypropylene grafted maleic anhydride as compatibilizer) were extruded and subsequently cold‐drawn into strands with a draw ratio of 10. The effects of compatibilizer and TiO 2 particles on the structure and properties of drawn strands were investigated. Upon addition of compatibilizer, the preferential location of TiO 2 particles shifted from the PET‐dispersed phase to the PP matrix, which brought about different structures of the drawn strands. Differential scanning calorimetry study provided indications for a heterogeneous nucleation effect of the PET fibrils on the PP matrix and of the TiO 2 particles on the PET fibrils. Dynamic mechanical analysis demonstrated that the mechanical properties of the drawn strands are strongly dependent on the strand structures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009