Composites Communications 22 (2020) 100442 Available online 20 August 2020 2452-2139/© 2020 Elsevier Ltd. All rights reserved. Compatibility, mechanical and rheological properties of hybrid rubber NR/ EPDM-g-MA/EPDM/graphene oxide nanocomposites: Theoretical and experimental analyses Mohammad Javad Azizli a, b, * , Mohammad Barghamadi c , Katayoon Rezaeeparto d , Masoud Mokhtary a , Somayeh Parham d a Department of Chemistry and Chemical Engineering, Rasht Branch, Islamic Azad University, Rasht, Iran b Zolal Gostar Rooz, Technical Inspection and Consulting Engineers CO, P.O.Box: 14139-74513, Tehran, Iran c Department of Rubber, Iran Polymer and Petrochemical Institute, P. O. Box: 14965-115, Tehran, Iran d Research Institute of Petroleum Industry, P.O. Box: 14857-33111, Tehran, Iran A R T I C L E INFO Keywords: NR/EPDM Graphene oxide Compatibilizer Carreau-Yasuda Mooney-Rivlin ABSTRACT In this study, a series of elastomeric nanocomposites based on specifc amounts of natural rubber (NR)/ethylene propylene diene monomer rubber (EPDM) blends which are compatibilized with ethylene propylene diene monomer-grafted-maleic anhydride (EPDM-g-MA) and different amounts of graphene oxide (GO) (1, 3, 5, 7 and 10 phr) were prepared with melt mixing method. Dispersion of nanoplatelets within rubber matrix were proven with transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The modifed micro- structure of samples showed that the fracture surfaces of nanocomposites were rougher than blend samples. Also, the addition of compatibilizer and nanoplatelets on mechanical and rheological properties of samples were evaluated. Theoretical and experimental mechanical properties of studied samples in correlation with their morphologies were studied with Mori-Tanaka and DMTA analysis, respectively. The mechanical properties of samples showed that by the incorporation of GO, fatigue strength, hardness, tensile strength, elongation-at-break and modulus increased. In end of all analysis was found good agreement between experimental and theoretical results. 1. Introduction Polymer blends containing of EPDM and NR have been known as a conventional blend Which is widely used in the rubber industry [1]. This important blend has many applications in engineering felds due to having special mechanical and physical properties such as ozone barrier, wear, thermal resistances and etc. Because of the different unsaturated bonds in EPDM structure compared to NR chains, maybe poor curing properties of this blend. Therefore, for compensation to this weak point EPDM-g-MA as compatibilizer is used [2–4]. In recently, elastomeric nanocomposites have been attracted many attentions in around the world. Accordingly, addition low amounts of nanoplatelets into the polymer blends due to having low aspect ratio led to improving their mechanical and rheological properties. Dispersion and distribution of nanoplatelets are recognized as two important fac- tors which have signifcant effect on all of properties. Therefore, the preparation method of nanocomposites is very important. Several techniques have been presented for preparing polymer nanocomposites, in among of all methods melt mixing has been known as best approach due to without using organic solvents, proper compatibility and using industrial techniques for production with different shapes. Enrichment matrix phases by nano fllers have been less attained [5–7]. In this method, nanoplatelets along with compatibilizers are used for increasing interactions between polymer chains and nanoplatelets. In this regard, many polymer types with polar and non-polar natures can be mixed together and preparing a polymer blend nanocomposite with appropriate morphology [8,9]. Polymer nanocomposites based on gra- phene oxide were known as progressive technologies which were pre- pared by using nano graphene [10,11]. This nanoplatelets has extensive applications in electronic devices such as sensors, actuators and other devices [12,13]. Graphene nanoplatelets have multi-layer structures which conducted to particular behaviors. Beside suitable properties, * Corresponding author. Department of Chemistry and Chemical Engineering, Rasht Branch, Islamic Azad University, Rasht, Iran. E-mail address: Mohammadjavad.azizli@gmail.com (M.J. Azizli). Contents lists available at ScienceDirect Composites Communications journal homepage: www.elsevier.com/locate/coco https://doi.org/10.1016/j.coco.2020.100442 Received 1 July 2020; Received in revised form 5 August 2020; Accepted 6 August 2020