Reinforced and toughened PP/PS composites prepared by Fused Filament Fabrication (FFF) with in-situ microfibril and shish-kebab structure

Abstract

In this work, in-situ microfibrillar composites (MFC) of polypropylene (PP)/polystyrene (PS) were produced by Fused Filament Fabrication (FFF) with a self-designed build platform. Due to the high shearing and stretching effect during the FFF process, PS phase underwent a large deformation. A large number of PS microfibrils could be observed in the samples. Meanwhile the molecular chain of PP was also stretched and arranged along the flow direction in the 3D Printing process. Finally, microfibrils, shish-kebab and hybrid shish-kebab crystal structures can be found and they make contributions to the mechanical performance. This work confirms the applicability of semi-crystalline polymer in FFF technology and discusses the development of phase morphology and crystalline morphology during printing. These obtained results will provide new ideas for broadening the amount of available materials and the application fields of FFF samples.