Influence of m ‐isopropenyl‐α,α‐dimethylbenzyl isocyanate grafted polypropylene on the interfacial interaction of wood‐flour/polypropylene composites

In this article, the effects of m ‐isopropenyl‐α,α‐dimethylbenzyl isocyanate grafted polypropylene ( m ‐TMI‐PP) on the interfacial interaction of wood‐flour/polypropylene (WF/PP) were investigated by means of scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry, dynamic rheological analysis, and mechanical properties tests. The experimental results demonstrated that m ‐TMI‐PP greatly improved the interfacial interaction between WF and PP. According to the DSC results, m ‐TMI‐PP made the crystallization temperature and the crystallization degree of PP in WF/ m ‐TMI‐PP/PP decrease when compared with WF/PP composite without m ‐TMI‐PP, but it was still higher than pure PP. These results demonstrated that WF presented the nucleate effect for the crystallization of PP and m ‐TMI‐PP improved the interfacial adhesive, which restrained the mobility of PP chain. The rheological analysis indicated that the complex viscosity, storage, and loss modular of WF/PP composite increased, and the tan δ decreased with the addition of m ‐TMI‐PP. This was attributed to the strong improvement effects of m ‐TMI‐PP on the interfacial interaction of the composites, and was further confirmed by the mechanical properties tests and SEM analysis of the composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008