The thermal and thermomechanical behaviors of Spartium junceum flour reinforced polypropylene composites: effects of treatment and flour content

Abstract

The effects of Spartium junceum (SJ) flour content, treatment time on the thermal and thermomechanical properties of polypropylene/Spartium junceum flour (PP/SJ) composites were studied. In order to improve the interfacial adhesion between the PP matrix and the SJ flour, SJ flour was treated with NaOH (2 wt%) for 8, 24 and 48 h at ambient temperature, respectively, and treated by vinyltrimethoxysilane (VTMS) (5 wt%). The results of thermogravimetric analysis (TGA) of SJ flour shows that the treatment improves the thermal stability of SJ flour. DSC analysis measurements illustrates that the addition of SJ flour increase the degree of crystallinity X c, which indicate that the SJ flour plays a significant role in heterogeneous nucleating of PP matrix. The chemical treatments significantly affect the storage modulus of composite, where E′ increases for composites with treated flour in comparison to the untreated ones.