Chemical modification of palygorskite with maleic anhydride modified polypropylene: Mechanical properties, morphology, and crystal structure of palygorskite/polypropylene nanocomposites

Abstract Maleic anhydride modified polypropylene (PP) (PP-g-MAH) was chemically grafted onto palygorskite (Pal) via the bridge linking of [3-(2-aminoethyl)aminopropyl]trimethoxysilane (Z-6020) and PP-g-MAH in the presence of ultrasonic oscillation. The modified Pal was added to a PP matrix as a nano-filler to prepare Pal/PP nanocomposites by melt blending. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to discern that PP-g-MAH and Z-6020 were chemically grafted onto Pal via acrylation between NH2 and anhydride groups. The Pal/PP nanocomposites were characterized by Scanning electron microscopy, transmission electron microscopy and wide angle X-ray diffraction. The toughness and strength of PP could be improved markedly by the addition of modified Pal. The modified Pal was dispersed uniformly in the PP matrix in the form of individual crystal needles, which demonstrated the presence of strong interactions between the modified Pal and PP. The modified Pal could induce the formation of β-form PP crystals and promote the motion of PP chains during crystallization.