Interfacial Phenomena of Newspaper Fiber-Reinforced Polypropylene Composite, Part I: The Development of Interfacial Interaction

In the process of developing interfacial interaction between newspaper fiber (NPF) and polypropylene (PP) by an intensive mixing, the morphological and microstructural characteristics which influence the mechanical behavior of the mixture were investigated by means of a scanning electron microscope (SEM) and a rheometer. The effects of mixing temperature and moisture content in the NPF on the mechanical behavior were elucidated. The development of interfacial interaction took place in two stages, in which the first stage took place over a relatively short time. In this stage, the fiber was not uniformly dispersed in the melted PP matrix. A fully developed interfacial interaction was not developed until the second stage. In this stage, the fiber was uniformly dispersed into the matrix and coated with PP. The mechanical strength of the composite was maximized in the second stage of mixing.