Recovered and Recycled Kraft Fibers as Reinforcement of PP Compositessss

Usefulness of a recovered and recycled Kraft fiber as reinforcement of polypropylene (PP) composites was investigated. Composites up to 50% of recycled Kraft fibers were prepared and increments of two times the ultimate tensile strength of non-reinforced matrix were achieved for those formulations comprising maleated polypropylene (MAH-PP) coupling agent. With the addition of MAH-PP coupling agent, hydrogen bonds as well as covalent linkages were revealed. Measurements of surface polarity, specific surface area, floatability tests and spectroscopic and microscopic analysis were used to demonstrate the interfacial union between the composite components. It was observed that the inhibition of these chemical interactions gave composites with the same ultimate tensile strength than those without MAH-PP coupling agent.