Influence of nanoparticle on hygroscopic thickness swelling rate of composites from hemp fiber and recycled plastic

Abstract In this study, the effect of nanoparticle on hygroscopic thickness swelling rate of composites from hemp fiber and recycled plastic was investigated. To meet this objective, hemp fiber was mixed with either virgin or recycled polypropylene (PP) at 50% by weight fiber loading. The samples were made by melt compounding and then injection molding. The concentration was varied as 0, 1, and 3 per hundred compounds (phc) for nanoclay. The amount of coupling agent was fixed at 2 phc for all formulations. The long-term thickness swelling rate of samples was evaluated by immersing them in water at room temperature for several weeks (up to 3000 h). The results indicated that whether or not virgin plastic is used has a significant effect on the thickness swelling of composites. The thickness swelling of the hemp fiber/recycled plastic composites was higher than those of virgin plastics. Furthermore, with the addition of nanoclay content in composites, thickness swelling decreased. The swelling rate parameter ( K _SR ) of the composites was influenced by plastics virginity and nanoclay. The minimum K _SR values were observed in composites made of 50VPP/50F/2C/3N. Morphological findings showed that samples containing 1 phc of nanoclay had higher order of intercalation and better dispersion.