Evaluation of toughening mechanisms of polypropylene/ethylene–octene copolymer/maleic anhydride‐grafted poly(ethylene‐co‐octene)/clay nanocomposite

Abstract

The toughness of a polypropylene (PP)/ethylene‐octene copolymer (EOC)/maleic anhydride‐grafted poly(ethylene‐co‐octene) (EOC‐g‐MA)/clay nanocomposite and blends of PP/EOC and PP/EOC/EOC‐g‐MA was investigated using Charpy impact and single‐edge‐notch tensile (SENT) tests. In order to understand the toughening mechanisms, impact fracture surfaces and damage zones of single‐edge‐notch samples were studied with scanning electron microscopy and transmission optical microscopy, respectively. It was observed that the addition of EOC‐g‐MA to PP/EOC blend led to improvements in both impact strength and fracture energy of SENT tests because of the enhanced compatibility of the blend, which resulted from reduced EOC particle size and improved interfacial adhesion, and the decreased crystallinity of PP. The incorporation of clay to PP/EOC/EOC‐g‐MA blend caused a further increase of the toughness, owing to the greater decrease in the size of elastomer particles, to the presence of clay tactoids inside the elastomer phase and presumably to debonding of clay layers during the low‐speed SENT tests. The results of microscopic observations showed that the main toughening mechanism in PP/EOC/EOC‐g‐MA blend and PP/EOC/EOC‐g‐MA/clay nanocomposite is crazing. Copyright © 2012 Society of Chemical Industry

Morphology and properties of polypropylene/ethylene-octene copolymer/clay nanocomposites with double compatibilizers

“…Because the modulus and strength of PP/EOC/EOC‐g‐MA/PP‐g‐MA blend are lower than those of PP/EOC while its toughness is higher, it can be concluded that the existence of the compatibilizers have affected the mechanical properties of nanocomposite too. Our previous studies showed adding EOC‐g‐MA exclusively to the PP/EOC blend led to a large enhancement in toughness because of its rubbery nature, the enhanced compatibility, and the reduced crystallinity of the blend. In contrast, the PP‐g‐MA used in this work is detrimental for the mechanical properties of PP/EOC/clay nanocomposite including tensile strength, tensile modulus, and impact strength …”

Effects of liquid crystal polymer and organoclay addition on the physical properties of high‐density polyethylene films

“…This route is also known as compounding, the most versatile, and practical way for modification of physical properties of thermoplastics. Structural, morphological, thermal, and mechanical properties of ternary polyolefin nanocomposites consisting of a polyolefin blend as matrix phase and a nanofiller as reinforcing material have been extensively studied . Moreover, some studies have focused on effects of nanofillers on microstructure formation of immiscible blends, in recent years.…”

Rubber‐toughened polyamide‐6 with a low thermal expansion coefficient: effect of preferential distribution of rubber and inorganic filler

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“…Hence, incorporating elastomer or rubber is an effective approach to improving impact resistance. 2,3 However, this incorporation often negatively affects the dimensional precision at high temperatures because the CLTE values of elastomers are higher than those of plastics. Although a finer dispersion of elastomer domains by enhancing the compatibility among the components may improve the impact resistance for a lower amount of elastomer, 4 the dimensional precision at high temperatures cannot be improved by this approach.…”