A Study on Creep Behavior of a Wood Flour-Polypropylene-Nanoclay Hybrid Composite

In this study, the effect of nanoclay particles content on creep behavior of wood flour/polypropylene composite was investigated. To meet this objective, wood flour was mixed with polypropylene at 60 % by weight fiber loading. The concentration was varied as 0, 3 and 5 per hundred compounds (phc) for nanoclay. The amount of coupling agent (PP-g-MA) was fixed at 2 phc for all formulations. The samples were made by melt compounding and injection molding. Firstly, the modulus of elasticity, flexural and tensile strength of composites was measured before performing the creep test. Then, the short term flexural and tensile creep test at 20% of ultimate bending load at 12 min was performed. The morphology of the nanocomposites has been examined by using x-ray diffraction and transmission electron microscopy. Results indicated that the creep deflection, relative creep and creep factor increases with increase of nanoclay up to 3 phc and then decreases with 5 phc nanoclay addition. Also, the effect of nanoclay was positive in terms of enhancing the mechanical properties of the composites. The morphological studies with XRD and TEM revealed that nanoclay distributed as intercalation structure in polymer matrix.