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Wei Yang - One of the best experts on this subject based on the ideXlab platform.

  • Toughening of polyamide 6 with β-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–Diene Rubber grafted with maleic anhydride blends
    Materials & Design, 2020
    Co-Authors: Li-feng Ma, Wei Yang, Wei-kang Wang, Qi Zhang, Li Gu, Ming-bo Yang
    Abstract:

    Abstract The toughening of polyamide 6 (PA 6) with β-nucleated thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene–propylene–Diene Rubber grafted with maleic anhydride (EPDM-g-MAH) blends was studied. A series of TPVs without and with different dosage of β-nucleating agent (β-NA) were prepared and used to toughen PA 6 at the same proportion. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements showed that β crystals of PP were effectively induced in the TPVs. The PA 6 blends toughened with β-nucleated TPVs (β-TPVs) exhibit significantly enhanced toughness, balanced mechanical properties and thermal properties compared with PA 6 toughened by TPV without β-NA or only by EPDM-g-MAH. Phase morphologies of the blends characterized by scanning electron microscopy (SEM) showed that better interfacial adhesion caused by the migration of β-NA from PP to PA 6/PP interface and PP/EPDM-g-MAH interface gives rise to more uniform dispersion and smaller size of the dispersed phase; moreover, the core–shell structure comprised of Rubber particles enveloped by PP on the surface, brings about easier and stronger interference of the stress field of EPDM phase.

  • conductive thermoplastic vulcanizates tpvs based on polypropylene pp ethylene propylene Diene Rubber epdm blend from strain sensor to highly stretchable conductor
    Composites Science and Technology, 2016
    Co-Authors: Shao Di Zheng, Rui Yan Zhang, Ming-bo Yang, Wei Yang
    Abstract:

    Abstract Conductive elastomeric materials of multi-walled carbon nanotube (MWCNT) filled thermoplastic vulcanizate (TPV) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blends were fabricated via different processing procedures, i.e., one-step and two-step methods, to control strain sensitivity aiming at applications from strain sensors to stretchable conductors. The phase size of cross-linked EPDM could be effectively tuned and the average diameter of EPDM particles was 550 nm for one-step TPV and 230 μm for two-step TPV. Uniform dispersion of MWCNTs in two-step TPV and serious aggregations of MWCNTs in one-step TPV were observed. Both TPVs showed excellent strain-resistance repeatability for 50 tensile and recovery cycles. The one-step-TPV showed a potential to be used as strain sensor due to a high gauge factor (GF) of 1004 at a strain of 100%, while the resistance for the two-step TPV composite was independent with strain even at a strain of 200%, resulting in a stretchable conductor with excellent resistance memory effect. The different strain sensitivity can be explained by the orientation of PP matrix. Moreover, the two-step TPV showed much lower electrical conductivity percolation threshold, 0.65 wt.%. This work provided a simple route to tune the strain sensitivity of MWCNTs filled TPVs based on PP/EPDM blends for applications from strain sensors to highly stretchable conductor through different processing procedures to control the morphologies and MWCNT dispersion.

  • Conductive thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blend: From strain sensor to highly stretchable conductor
    Composites Science and Technology, 2016
    Co-Authors: Li-feng Ma, Shao Di Zheng, Rui Yan Zhang, Zheng Ying Liu, Rui Dou, Rui-ying Bao, Ming-bo Yang, Wei Yang
    Abstract:

    Conductive elastomeric materials of multi-walled carbon nanotube (MWCNT) filled thermoplastic vulcanizate (TPV) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blends were fabricated via different processing procedures, i.e., one-step and two-step methods, to control strain sensitivity aiming at applications from strain sensors to stretchable conductors. The phase size of cross-linked EPDM could be effectively tuned and the average diameter of EPDM particles was 550 nm for one-step TPV and 230 μm for two-step TPV. Uniform dispersion of MWCNTs in two-step TPV and serious aggregations of MWCNTs in one-step TPV were observed. Both TPVs showed excellent strain-resistance repeatability for 50 tensile and recovery cycles. The one-step-TPV showed a potential to be used as strain sensor due to a high gauge factor (GF) of 1004 at a strain of 100%, while the resistance for the two-step TPV composite was independent with strain even at a strain of 200%, resulting in a stretchable conductor with excellent resistance memory effect. The different strain sensitivity can be explained by the orientation of PP matrix. Moreover, the two-step TPV showed much lower electrical conductivity percolation threshold, 0.65 wt.%. This work provided a simple route to tune the strain sensitivity of MWCNTs filled TPVs based on PP/EPDM blends for applications from strain sensors to highly stretchable conductor through different processing procedures to control the morphologies and MWCNT dispersion.

  • Toughening of polypropylene with β-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–Diene Rubber blends
    Materials & Design, 2013
    Co-Authors: Li-feng Ma, Wei Yang, Wei-kang Wang, Ming-bo Yang
    Abstract:

    Abstract A series of dynamically vulcanized isotactic polypropylene (PP)/ethylene–propylene–Diene Rubber thermoplastic vulcanizates (TPVs) containing different content of β-nucleating agent (β-NA) were prepared and introduced into isotactic PP matrix as a toughening agent. The effect of β-nucleated TPVs (β-TPVs) on the toughness and other properties of PP were studied. Differential scanning calorimetry and wide-angle X-ray diffraction results indicated that the β-crystallinity and the relative content of β-phase in β-TPVs samples and the toughened blends increased with the content of β-NA increasing. The notched impact strength of PP toughened by β-TPVs, with limited loss in the tensile strength and rigidity, showed an almost linear increase with increasing β-NA content. Especially when the content of β-NA was 0.5 wt%, the impact strength of the toughened blends was ten times more than that of pure PP. The toughening mechanism based on classical Rubber toughening mechanisms was discussed and a synergic toughening mechanism was proposed.

Young Wook Chang - One of the best experts on this subject based on the ideXlab platform.

  • Triple-shape memory effects of modified semicrystalline ethylene–propylene–Diene Rubber/poly(ε-caprolactone) blends
    European Polymer Journal, 2015
    Co-Authors: Muhammad Kashif, Young Wook Chang
    Abstract:

    Abstract Triple-shape memory polymers (T-SMPs) were prepared by melt blending of a 3-amino-1,2,4-triazole modified semicrystalline maleated ethylene–propylene–Diene Rubber (A-EPDM), which forms a supramolecular hydrogen-bonded network, with poly(e-caprolactone) (PCL). The effect of PCL content (10–50 wt%) on the thermomechanical and triple-shape memory properties of the A-EPDM/PCL blends was investigated. Scanning electron micrographs showed a phase-separated morphology, in which PCL phase was dispersed in a continuous A-EPDM matrix. Fourier transform infrared spectroscopy and differential scanning calorimetry results revealed a certain degree of compatibility between A-EPDM and PCL in the blends. Dynamic mechanical analysis of the blends showed that the blends form a physically crosslinked network structure and there are sudden drops in the storage modulus at well-separated temperatures in the range of 20–140 °C corresponding to the crystalline melting transition of each component in the blends. These structural features of the blend—two well-separated crystalline melting transitions within a physically crosslinked network—enable this blend system to exhibit triple-shape memory behavior with two different stages of temporary shape fixing and then step-wise shape recovery. These blend-based T-SMPs show melt processability and recyclability.

  • Triple-shape memory effects of modified semicrystalline ethylene-propylene-Diene Rubber/poly(ε-caprolactone) blends
    European Polymer Journal, 2015
    Co-Authors: Kashif Muhammad, Young Wook Chang
    Abstract:

    Abstract Triple-shape memory polymers (T-SMPs) were prepared by melt blending of a 3-amino-1,2,4-triazole modified semicrystalline maleated ethylene-propylene-Diene Rubber (A-EPDM), which forms a supramolecular hydrogen-bonded network, with poly(ε-caprolactone) (PCL). The effect of PCL content (10-50 wt%) on the thermomechanical and triple-shape memory properties of the A-EPDM/PCL blends was investigated. Scanning electron micrographs showed a phase-separated morphology, in which PCL phase was dispersed in a continuous A-EPDM matrix. Fourier transform infrared spectroscopy and differential scanning calorimetry results revealed a certain degree of compatibility between A-EPDM and PCL in the blends. Dynamic mechanical analysis of the blends showed that the blends form a physically crosslinked network structure and there are sudden drops in the storage modulus at well-separated temperatures in the range of 20-140°C corresponding to the crystalline melting transition of each component in the blends. These structural features of the blend - two well-separated crystalline melting transitions within a physically crosslinked network - enable this blend system to exhibit triple-shape memory behavior with two different stages of temporary shape fixing and then step-wise shape recovery. These blend-based T-SMPs show melt processability and recyclability.

  • Heat shrinkable behaviour of supramolecular hydrogen bonded maleated ethylene propylene Diene Rubber and maleated high density polyethylene blend
    Polymer - Plastics Technology and Engineering, 2007
    Co-Authors: Joy K. Mishra, Dong-kook Kim, Young Wook Chang, Padma L. Nayak
    Abstract:

    Maleated high density polyethylene and maleated ethylene propylene Diene Rubber (50 wt%/50 wt%) was blended in presense of 3-amino-1,2,4-triazole (ATA). The supramolecular hydrogen bonding was characterized by FTIR and dynamic mechanical analysis. The crystallinity of the blend system was studied by XRD and it was observed that supramolecular hydrogen bonding decreases the crystallinity of the blend. The supramolecular hydrogen bonded network improves heat shrinkability of the blend.

  • Effect of supramolecular hydrogen bonded network on the properties of maleated ethylene propylene Diene Rubber/maleated high density polyethylene blend based thermoplastic elastomer
    Materials Letters, 2006
    Co-Authors: Young Wook Chang, Joy K. Mishra
    Abstract:

    Abstract A thermoplastic elastomer having supramolecular hydrogen bonded network was prepared by the melt mixing of maleated ethylene propylene Diene Rubber and maleated high density polyethylene in presence of 3-amino-1,2,4-triazole (ATA), which acts as a coupling agent. The hydrogen bonded network formation in the blend system enhanced the physical properties of the blend. The storage modulus and glass transition temperature of the elastomer–plastic blend containing ATA was found to be increased as compared to the blend without ATA. It was observed that polyblends containing ATA exhibit a Rubbery plateau above the melting temperature of the maleated high density polyethylene. Reprocessability study confirmed the thermoplastic elastomeric nature of the polyblend system.

  • Effect of supramolecular hydrogen bonded network on the properties of maleated ethylene propylene Diene Rubber/maleated high density polyethylene blend based thermoplastic elastomer
    Materials Letters, 2006
    Co-Authors: Young Wook Chang, Joy K. Mishra, Sun Keun Kim, Dong-kook Kim
    Abstract:

    A thermoplastic elastomer having supramolecular hydrogen bonded network was prepared by the melt mixing of maleated ethylene propylene Diene Rubber and maleated high density polyethylene in presence of 3-amino-1,2,4-triazole (ATA), which acts as a coupling agent. The hydrogen bonded network formation in the blend system enhanced the physical properties of the blend. The storage modulus and glass transition temperature of the elastomer-plastic blend containing ATA was found to be increased as compared to the blend without ATA. It was observed that polyblends containing ATA exhibit a Rubbery plateau above the melting temperature of the maleated high density polyethylene. Reprocessability study confirmed the thermoplastic elastomeric nature of the polyblend system. © 2006 Elsevier B.V. All rights reserved.

Dong-kook Kim - One of the best experts on this subject based on the ideXlab platform.

Ming-bo Yang - One of the best experts on this subject based on the ideXlab platform.

  • Toughening of polyamide 6 with β-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–Diene Rubber grafted with maleic anhydride blends
    Materials & Design, 2020
    Co-Authors: Li-feng Ma, Wei Yang, Wei-kang Wang, Qi Zhang, Li Gu, Ming-bo Yang
    Abstract:

    Abstract The toughening of polyamide 6 (PA 6) with β-nucleated thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene–propylene–Diene Rubber grafted with maleic anhydride (EPDM-g-MAH) blends was studied. A series of TPVs without and with different dosage of β-nucleating agent (β-NA) were prepared and used to toughen PA 6 at the same proportion. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements showed that β crystals of PP were effectively induced in the TPVs. The PA 6 blends toughened with β-nucleated TPVs (β-TPVs) exhibit significantly enhanced toughness, balanced mechanical properties and thermal properties compared with PA 6 toughened by TPV without β-NA or only by EPDM-g-MAH. Phase morphologies of the blends characterized by scanning electron microscopy (SEM) showed that better interfacial adhesion caused by the migration of β-NA from PP to PA 6/PP interface and PP/EPDM-g-MAH interface gives rise to more uniform dispersion and smaller size of the dispersed phase; moreover, the core–shell structure comprised of Rubber particles enveloped by PP on the surface, brings about easier and stronger interference of the stress field of EPDM phase.

  • conductive thermoplastic vulcanizates tpvs based on polypropylene pp ethylene propylene Diene Rubber epdm blend from strain sensor to highly stretchable conductor
    Composites Science and Technology, 2016
    Co-Authors: Shao Di Zheng, Rui Yan Zhang, Ming-bo Yang, Wei Yang
    Abstract:

    Abstract Conductive elastomeric materials of multi-walled carbon nanotube (MWCNT) filled thermoplastic vulcanizate (TPV) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blends were fabricated via different processing procedures, i.e., one-step and two-step methods, to control strain sensitivity aiming at applications from strain sensors to stretchable conductors. The phase size of cross-linked EPDM could be effectively tuned and the average diameter of EPDM particles was 550 nm for one-step TPV and 230 μm for two-step TPV. Uniform dispersion of MWCNTs in two-step TPV and serious aggregations of MWCNTs in one-step TPV were observed. Both TPVs showed excellent strain-resistance repeatability for 50 tensile and recovery cycles. The one-step-TPV showed a potential to be used as strain sensor due to a high gauge factor (GF) of 1004 at a strain of 100%, while the resistance for the two-step TPV composite was independent with strain even at a strain of 200%, resulting in a stretchable conductor with excellent resistance memory effect. The different strain sensitivity can be explained by the orientation of PP matrix. Moreover, the two-step TPV showed much lower electrical conductivity percolation threshold, 0.65 wt.%. This work provided a simple route to tune the strain sensitivity of MWCNTs filled TPVs based on PP/EPDM blends for applications from strain sensors to highly stretchable conductor through different processing procedures to control the morphologies and MWCNT dispersion.

  • Conductive thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blend: From strain sensor to highly stretchable conductor
    Composites Science and Technology, 2016
    Co-Authors: Li-feng Ma, Shao Di Zheng, Rui Yan Zhang, Zheng Ying Liu, Rui Dou, Rui-ying Bao, Ming-bo Yang, Wei Yang
    Abstract:

    Conductive elastomeric materials of multi-walled carbon nanotube (MWCNT) filled thermoplastic vulcanizate (TPV) based on polypropylene (PP)/ethylene-propylene-Diene Rubber (EPDM) blends were fabricated via different processing procedures, i.e., one-step and two-step methods, to control strain sensitivity aiming at applications from strain sensors to stretchable conductors. The phase size of cross-linked EPDM could be effectively tuned and the average diameter of EPDM particles was 550 nm for one-step TPV and 230 μm for two-step TPV. Uniform dispersion of MWCNTs in two-step TPV and serious aggregations of MWCNTs in one-step TPV were observed. Both TPVs showed excellent strain-resistance repeatability for 50 tensile and recovery cycles. The one-step-TPV showed a potential to be used as strain sensor due to a high gauge factor (GF) of 1004 at a strain of 100%, while the resistance for the two-step TPV composite was independent with strain even at a strain of 200%, resulting in a stretchable conductor with excellent resistance memory effect. The different strain sensitivity can be explained by the orientation of PP matrix. Moreover, the two-step TPV showed much lower electrical conductivity percolation threshold, 0.65 wt.%. This work provided a simple route to tune the strain sensitivity of MWCNTs filled TPVs based on PP/EPDM blends for applications from strain sensors to highly stretchable conductor through different processing procedures to control the morphologies and MWCNT dispersion.

  • The influence of mixing order on the phase inversion and crystallization behavior of polyamide 6/maleic anhydride-g-ethylene–propylene–Diene Rubber/high-density polyethylene blend:
    Journal of Elastomers and Plastics, 2014
    Co-Authors: Wei Wang, Yan Zhou, Lan-peng Li, Ming-bo Yang
    Abstract:

    In this work, the morphology and crystallization behavior of polyamide 6 (PA6)/maleic anhydride-grafted-ethylene–propylene–Diene Rubber (MAH-g-EPDM)/high-density polyethylene (HDPE) blends with different ratios of the components were studied. In order to study the influence of both thermodynamics and kinetic factors, the interfacial tension between various polymer pairs was taken into account and two processing methods were used. Contact angle measurements and rheological relaxation time simulation were used to calculate the interfacial tension. It was found that because of the reaction between PA6 and MAH-g-EPDM, the value of interfacial tension of PA6/MAH-g-EPDM binary blends calculated by the contact angle measurement was not correct and the real value α = 0.97 mN m−1 was calculated by rheological relaxation time simulation. The two processing methods (one-step and two-step processing methods) led to different crystallization behaviors with different morphologies of the blends.

  • Toughening of polypropylene with β-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–Diene Rubber blends
    Materials & Design, 2013
    Co-Authors: Li-feng Ma, Wei Yang, Wei-kang Wang, Ming-bo Yang
    Abstract:

    Abstract A series of dynamically vulcanized isotactic polypropylene (PP)/ethylene–propylene–Diene Rubber thermoplastic vulcanizates (TPVs) containing different content of β-nucleating agent (β-NA) were prepared and introduced into isotactic PP matrix as a toughening agent. The effect of β-nucleated TPVs (β-TPVs) on the toughness and other properties of PP were studied. Differential scanning calorimetry and wide-angle X-ray diffraction results indicated that the β-crystallinity and the relative content of β-phase in β-TPVs samples and the toughened blends increased with the content of β-NA increasing. The notched impact strength of PP toughened by β-TPVs, with limited loss in the tensile strength and rigidity, showed an almost linear increase with increasing β-NA content. Especially when the content of β-NA was 0.5 wt%, the impact strength of the toughened blends was ten times more than that of pure PP. The toughening mechanism based on classical Rubber toughening mechanisms was discussed and a synergic toughening mechanism was proposed.

Harjeet Singh - One of the best experts on this subject based on the ideXlab platform.

  • Thermal Stability and Crystallization Behavior of TER Blends of Isotactic Polypropylene (iPP)/Ethylene-Propylene Diene Rubber (EPDM)/Nitrile Rubber (NBR)
    International Journal of Polymeric Materials, 2012
    Co-Authors: Krishna Dutt, Romesh Soni, Harjeet Singh
    Abstract:

    The blends of isotatic polypropylene (iPP), ethylene-propylene Diene Rubber (EPDM), and nitrite Rubber (NBR) were prepared using dimethylol phenolic resin as a crosslinking system. The dynamically crosslinked blends of iPP/EPDM/NBR showed superior thermal stability to that of virgin isotactic polypropylene (iPP). Dynamic crosslinking rendered the vulcanizate thermally more stable as compared to uncrosslinked blends, which can be attributed due to the variations in degree of crosslinking and degree of crystallinity. Crystallization of iPP in the blends of iPP/EPDM/NBR was also studied through Temperature Modulated Differential Scanning Calorimetry (TMDSC). Other detailed analysis of endotherm peaks obtained after first and second melts in terms of heat of enthalpy, degree of undercooling, and degree of crystallinity were also evaluated. Various kinetic parameters were also determined. Degree of crosslinking increases the interfacial adhesion between the iPP and EPDM/NBR phases. Dimethylol phenolic resin us...

  • RETRACTED ARTICLE: Effect of dynamic cross-linking on melt rheological properties of isotactic polypropylene (iPP)/ethylene–propylene Diene Rubber (EPDM)/nitrile Rubber (NBR) elastomeric blends
    International Journal of Plastics Technology, 2011
    Co-Authors: Krishna Dutt Chauhan, R. K. Soni, Harjeet Singh
    Abstract:

    An attempt has been made to study the melt rheological properties of uncross-linked and dynamically cross-linked isotactic polypropylene (iPP)/ethylene-propylene-Diene Rubber (EPDM)/Nitrile Rubber (NBR) elastomeric blends, at blending ratios 10–40 wt.%, EPDM/NBR are reported. Blends were prepared by melt blending in an internal mixture at 190 °C and various rheological parameters have been evaluated at 220 °C by single screw capillary rheometer. Cross-linking was performed with resole type dimethylol phenolic resin. The effects of (i) blends composition (ii) shear stress/shear rate on melt viscosity (iii) flow characteristics and shear sensitivity at processing (iv) melt elasticity of the extrudate and (v) dynamic vulcanization effect on the processing characteristics were studied. It was found that the melt viscosity increases with the increasing EPDM/NBR concentration and decrease with increasing intensity of the shear mixing of all the blend compositions. As compared to the uncross-linked blends, dynamically cross-linked blends displayed high pseudoplastic behavior and provides unique processing characteristics that enable to perform well in both injection molding and extrusion process. The high viscosity at low shear rate provides the integrity of the extrudate during extrusion, and the low viscosity at high shear rate enabling low injection pressure and less injection time. Also the low die-swell characteristics of cross-linked blends also gave high precision for dimensional control during processing (extrusion).

  • RETRACTED ARTICLE: Investigation on the improvement of physico-mechnical, viscoelastic and morphological properties of isotactic polypropylene (iPP)/ethylene-propylene Diene Rubber (EPDM)/ nitrile Rubber (NBR)
    International Journal of Plastics Technology, 2010
    Co-Authors: Krishna Dutt Chauhan, Rakesh Kumar Soni, Harjeet Singh
    Abstract:

    An attempt has been made to study the mechanical, viscoelastic and morphological behavior of various dynamically cross-linked blends of isotactic polypropylene (iPP) with ethylene-propylene Diene Rubber (EPDM) and nitrile Rubber (NBR) were examined and compared with these of uncross-linked blends of iPP/EPDM/NBR. These blends were prepared by melt blending in an internal mixer at 190 °C in the composition range of 10–40 wt. % EPDM/NBR elastomeric content. The variation in the strength of fibrils of the craze, yield stress and the number density of the EPDM/NBR elastomeric domains (morphology) which are important factors for enhancing the interfacial adhesion and toughness in dynamically cross-linked blends were determined. The toughness and ductility of these blends were discussed with main emphasis on the composition between crack formation and the degree of plastic deformation through crazing and shear yielding. The physico-mechanical properties such as hardness, impact strength, flexural strength and flexural modulus of dynamically cross-linked blends were found to be consistent and displayed enhanced mechanical properties values as compared with uncross-linked blends. The decreases in crystallinity and nucleation effect in cross-linked blends of iPP/EPDM/NBR were considered to contribute in the improvement in the impact strength behavior of the blends prepared.

  • Effect of dynamic cross-linking on mixing torque behavior and tensile yield behavior of isotactic polypropylene (iPP) / ethylene-propylene Diene Rubber (EPDM) /nitrile Rubber (NBR) elastomeric blends
    Journal of Polymer Research, 2009
    Co-Authors: Soni Rk, Krishna Dutt, Harjeet Singh, Priyanka Arora
    Abstract:

    The mixing torque behavior of ter blends of isotactic-polypropylene (iPP) with ethylene-propylene Diene Rubber (EPDM)/Nitrile Rubber (NBR) was studied with the help of Rheometer using resole type phenolic resin as a cross-linking agents. Systematic changes with varying blend composition were observed in stress-strain behavior in the yield region viz., width of yield peak, work of yield, yield stress and yield strain. Analysis of yield stress data was made on the basis of various mathematical expressions of first power and two-thirds power laws of blend composition dependence and the porosity model. It led to consistent result from the expressions about the variation of stress concentration effect in both uncross-linked and cross-linked blend systems. With the aid of scanning electron microscopy (SEM) shapes and sizes of dispersed elastomer phase (EPDM / NBR) domains at varying blend compositions were studied.