The edges of the holes where POE have been extracted are quite smooth. This confirms that a weak interfacial adhesion between the two phases which arises as a result of the poor compatibility between PA6 and POE. Figure 10. SEM micrographs of cryo-fractured surfaces by heptane of PA6/PP/organoclay toughened by (a) POE, (b) maleated POE A similar result was observed for the nanocomposites system toughened with EPR and EPRgMAH as shown in Figure 11. Figure 11. SEM micrographs of cryo-fractured surfaces by heptane of PA6/PP/organoclay toughened by (a) EPR, (b) maleated EPR. In order to have an efficient stress transfer between two phases, the rubber particles should be well dispersed so that they can act efficiently as stress concentrator, and they should be well bonded to polymer matrix.29 In this work, when PA6/PP/elastomer blend cooled from the melt, most elastomer will shrink more than the polymer matrix. For the PA6/PP/unmaleated POE blend, the debonding will thus occur because the absence of good adhesion between POE and PA6/PP phase. As mentioned earlier the succinic anhydride group of the maleic anhydride grafted POE is able to react with PA6 terminal group to form POEgPA6 copolymer that strongly tends to concentrate at PA6/PP interfaces during melt processing.10 According to Liang and Li,30 when rubber was grafted with suitable content of MA, the rubber particles were dispersed uniformly in the continuous PA6 matrix and the PP was encapsulated by thin layers of rubber (i.e., shell-core structure). When highly dispersed, the rubbery phase act as an effective stress concentrator and enhances both crazing and shear yielding in the matrix. Since both processes can dissipate large amount of energy, there is significant increase in the toughness of the nanocomposites toughened with POEgMAH.26 Table III summarized the size distribution of POE domain from measurement of a set of SEM micro-graph on cryo-fractured surfaces. Table III. The average of elastomer particle size in PA6/PP nanocomposites
The edges of the holes where POE have been extracted are quite smooth. This confirms that a weak interfacial adhesion between the two phases which arises as a result of the poor compatibility between PA6 and POE. Figure 10. SEM micrographs of cryo-fractured surfaces by heptane of PA6/PP/organoclay toughened by (a) POE, (b) maleated POE A similar result was observed for the nanocomposites system toughened with EPR and EPRgMAH as shown in Figure 11. Figure 11. SEM micrographs of cryo-fractured surfaces by heptane of PA6/PP/organoclay toughened by (a) EPR, (b) maleated EPR. In order to have an efficient stress transfer between two phases, the rubber particles should be well dispersed so that they can act efficiently as stress concentrator, and they should be well bonded to polymer matrix.29 In this work, when PA6/PP/elastomer blend cooled from the melt, most elastomer will shrink more than the polymer matrix. For the PA6/PP/unmaleated POE blend, the debonding will thus occur because the absence of good adhesion between POE and PA6/PP phase. As mentioned earlier the succinic anhydride group of the maleic anhydride grafted POE is able to react with PA6 terminal group to form POEgPA6 copolymer that strongly tends to concentrate at PA6/PP interfaces during melt processing.10 According to Liang and Li,30 when rubber was grafted with suitable content of MA, the rubber particles were dispersed uniformly in the continuous PA6 matrix and the PP was encapsulated by thin layers of rubber (i.e., shell-core structure). When highly dispersed, the rubbery phase act as an effective stress concentrator and enhances both crazing and shear yielding in the matrix. Since both processes can dissipate large amount of energy, there is significant increase in the toughness of the nanocomposites toughened with POEgMAH.26 Table III summarized the size distribution of POE domain from measurement of a set of SEM micro-graph on cryo-fractured surfaces. Table III. The average of elastomer particle size in PA6/PP nanocomposites
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