Isolation, characterization, and incorporation of microfibrils and microcrystals from Typha domingensis Pers. As impact strength reinforcer of polypropylene matrix composite using stearic acid as interfacial modifier

Microcellulose has shown advantageous character as a reinforcement in polymeric materials and produces relatively light compounds with high specific properties. This research aimed to obtain microcellulose (crystals and fibers) from the macrophyte Typha domingensis for use as a polypropylene reinforcement material for impact strength improvement and to use stearic acid as an interfacial modifier (surfactant) between the polypropylene and cellulosic materials. A commercial cellulose was used to compare the effectiveness of the microcellulose isolated from the macrophyte. The results demonstrated the procedures were efficient at obtaining microcellulose. The analysis of the chemical composition indicated an increase in the α-cellulose content from 63.2% in the raw material to 97.9% in the bleached cellulose. The X-ray diffraction patterns showed that the chemical treatments changed the crystallinity. The thermogravimetric analysis revealed an increase in the thermal stability of the bleached cellulose compared with that of the raw material. The thermal stability of the macrophyte was higher than that of commercial cellulose. The scanning electron micrographs revealed the presence of longitudinal slits that favored interactions with the polymer matrix. The impact strength was greatly improved for the composites compared with the pure polypropylene.