Effect of EPDM‐g‐MAH on the morphology and properties of PA6/EPDM/HDPE ternary blends

Abstract

The formation of core‐shell morphology within the dispersed phase was studied for composite droplet polymer‐blend systems comprising a polyamide‐6 matrix, ethylene‐propylene‐diene terpolymer (EPDM) shell and high density polyethylene (HDPE) core. In this article, the effect of EPDM with different molecular weights on the morphology and properties of the blends were studied. To improve the compatibility of the ternary blends, EPDM was modified by grafting with maleic anhydride (EPDM‐g‐MAH). It was found that core‐shell morphology with EPDM‐g‐MAH as shell and HDPE as core and separated dispersion morphology of EPDM‐g‐MAH and HDPE phase were obtained separately in PA6 matrix with different molecular weights of EPDM‐g‐MAH in the blends. DSC measurement indicated that there may be some co‐crystals in the blends due to the formation of core‐shell structure. Mechanical tests showed that PA6/EPDM‐g‐MAH/HDPE ternary blends with the core‐shell morphology exhibited a remarkable rise in the elongation at break. With more perfect core‐shell composite droplets and co‐crystals, the impact strength of the ternary blends could be greatly increased to 51.38 kJ m−2, almost 10 times higher than that of pure PA6 (5.50 kJ m−2). POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

Control of multilayered core–shell dispersed particles in HPP/EPR/EbP blends and its influences on crystallization and dynamic mechanical behavior

“…A similar conclusion can be drawn not only in IPC, but also in other systems [16e19]. Yang et al [16,17] found the impact strength of PA6/EPDM-g-MA/HDPE blends with coreeshell dispersed phase greatly increased, compared with other structure (dispersed separately or partial capsulation structure). Wilkinson et al [18] regarded that the coreeshell PA6/SEBS particles in PP matrix resulted in a huge increase in charpy impact strength with respect to other toughened PP.…”

“…It is interesting that the melting peak at about 120 C for the samples crystallized non-isothermally appears a weak composition dependence: it drops with the decrease of EbP component. Located in the core of coreeshell particles, PE chains in EbP can fold in pure ethylene chains environment due to utter incompatibility of EPR/PE [16,29]. Higher EbP content in blends offers greater concentration of PE so that nucleation and crystallization behavior are enhanced easily.…”

Effect of Maleated Styrene/Ethylene-co-Butylene/Styrene on the Dispersed Particles Size and Mechanical Properties of Polyamide 6/Poly(styrene-co-acrylonitrile)/Poly(styrene-b-(ethylene-co-butylene)-b-styrene) Ternary Blends

“…This model has been used frequently by researchers for the prediction of the morphology of ternary blends. [3][4][9][10][11][12][13][14] It is worth mentioning that there is another complex morphology that has received less attention. It consists of the core-shell morphology together with dispersed particles of the shell-forming component.…”

“…Downloaded by [Stony Brook University] at 10:23 02 November 2014 Furthermore, it is recognized that there is a close correlation between the morphology and mechanical properties of ternary blends. This relationship is of current interest to a number of researchers [e.g., [2][3][4].…”

“…[1][2][3][4] Basically, there are three kinds of phase structures in ternary systems: (1) the components of the dispersed phases are dispersed separately; (2) one component is encapsulated by another component, forming core-shell particles dispersed in the third phase; (3) in an intermediate state, partial encapsulation of one dispersed component by another one could occur. [4][5][6][7][8][9][10] Hobbs et al [7] showed that the morphology of ternary blends can be predicted through knowledge of the interfacial tension between the components of the blends. They tried to examine the encapsulation in a number of ternary blends.…”