Elastomer/thermoplastic modified epoxy nanocomposites: The hybrid effect of ‘micro’ and ‘nano’ scale Poornima Vijayan P. a , Debora Puglia b, *, Mariam Ali S.A. Al-Maadeed a , Jose. M. Kenny b , Sabu Thomas c,d, ** a Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar b Materials Engineering Centre, University of Perugia, Department of Civil and Environmental Engineering, Strada di Pentima 4–05100  Terni, Italy c International and Inter University Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Priyadarshini Hills, Kottayam, Kerala 686560, India d School of Chemical Sciences, Mahatma Gandhi University, Priyadarshini Hills, Kottayam, Kerala 686560, India A R T I C L E I N F O Article history: Received 2 November 2016 Received in revised form 11 March 2017 Accepted 16 March 2017 Available online xxx Keywords: Epoxy thermoset Nanocomposites Epoxy hybrid systems Rubber toughened epoxy nanocomposites Thermoplastic toughened epoxy nanocomposites A B S T R A C T The approach of simultaneously exploit the use of microscale elastomers/thermoplastics and nanoscale fillers for the modification of epoxy systems is presently an active research topic. Such hybrid modification of epoxy primarily helps to tailor multiple mechanical properties, without compromising other required properties. The current review reports about the development and properties of multicomponent epoxy systems modified with both elastomers/thermoplastics and nanofillers, on the basis of an updated literature survey. For a better understanding and comparison, the review initially provides a short discussion on key findings in binary blends of epoxy and elastomers/thermoplastic and binary epoxy nanocomposites. Successful studies dealing with multicomponent epoxy systems are also reported, where it is demonstrated that microscale modification individually, sometimes synergistically, enhances the fracture toughness of epoxy without affecting the properties optimized by nanoscale modification. The mutual role of microscale elastomer/thermoplastic and nanoscale filler on morphology, cure reaction, mechanical and thermal properties of epoxy multicomponent system is discussed. The complex interaction between the micro- and nano-phases determines phase separated morphologies in the multicomponent system, essentially related to the function of microscale modifiers in dispersion/intercalation/distribution of nanofillers and to the role of nanofillers in phase separation kinetics and mechanisms. The specific effect of nanofillers in phase separation mechanisms for epoxy blends, that place via nucleation and growth (NG) and spinodal decomposition, is analysed looking at the final morphology and hence performance of multicomponent system. Moreover, the fracture mechanism that operates in such multicomponent epoxy systems is discussed. Abbreviations: ABS, poly(acrylonitrile-co-butadiene-co-styrene); ATBN, amine-terminated poly(butadiene-co-acrylonitrile); BCPs, block copolymers; BF3.EA, boron trifluoride monoethylamine; CFRP, carbon-fibre reinforced-plastic; CNF, carbon nanofibers; CNT, carbon nanotubes; CRGO, chemically reduced graphene oxide; CRBN, carboxyl-randomized liquid butadiene–acrylonitrile rubber; CSR, core-shell rubbers; CTBN, carboxyl terminated poly(butadiene-co-acrylonitrile); CTPB, carboxyl- terminated polybutadiene; DDA, Dicyanodiamide; DDM, 4, 4 0 -diaminodiphenylmethane; DDS, 4, 4 0 -diaminodiphenyl sulfone; Epoxy/SiC/CTBN_M2, Epoxy hybrid by mixing CTBN in sonicated epoxy/SiC mixture; Epoxy/SiC/CTBN_M1, Epoxy hybrid by sonicating SiC nanofibers in epoxy/CTBN mixture; fCNT, N-octyl-functionalized CNT; ETBN, epoxy terminated poly(butadiene-co-acrylonitrile); FRP, fibre reinforced-plastic; GFRP, glass fibre reinforced plastic; GO, graphene oxide; GnP, graphene nanoplatelets; HBPs, hyperbranched polymers; HLNR, hydroxyl terminated liquid natural rubber; HNT, halloysite nanotube; HPEEK, hydroxylated poly (ether ether ketone); HPMM, high pressure mixing method; HTBN, hydroxyl-terminated poly(butadiene-co-acrylonitrile); HTPB, hydroxyl terminated polybutadiene; MA, maleic anhydride; MBS, methacrylated butadiene-styrene copolymer; M-NCDSUs, micro-nano constrained damping structure units; MMT, montmorillonite organoclays; MWCNTs, multiwalled carbon nanotubes; MWCNT–COOHs, carboxylic acid functionalised multi-walled carbon nanotubes; MWCNT-NH2s, amino-functionalized multiwalled carbon nanotubes; PA, polyamides; PCL, poly(e-caprolactone); PEEKMOH, poly ether ether ketone with pendant methyl groups; PEI, poly(ether imide); PEO, poly(ethylene oxide); PEO–PBO, poly(ethylene oxide)-b- poly-(butylene oxide); PEO–PEE, poly(ethylene oxide)-b-poly(ethyl ethylene); PEO–PEP, (ethylene oxide)-b-poly(ethylene-alt-propylene); PEO–PPO, poly(ethyleneoxide)-b- poly(propylene oxide); PEO–PPO–PEO, poly(ethyleneoxide)-b-poly(propylene oxide)-b-poly(ethylene oxide); PES, poly(ether sulfone); PMMA, poly(methyl-methacrylate); PMMA–PS, poly(methyl methacrylate)-b-polystyrene; PR, powdered rubber; PS–PB, polystyrene-b-polybutadiene; PS-PB-PS, poly(styrene-b-butadiene-b-styrene); PS-PEO, poly(styrene-b-ethylene oxide); RIFT, Resin Infusion under Flexible Tooling; RTM, Resin Transfer Moulding; S-CSR, polysiloxane coreshell rubber; SD, spinodal decomposition; SiC NWs, silicon carbide nanowires; VARTM, vacuum assisted resin transfer moulding. * Corresponding author. ** Corresponding author at: International and Inter University Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Priyadarshini Hills, Kottayam, Kerala 686560, India. E-mail addresses: debora.puglia@unipg.it (D. Puglia), sabuchathukulam@yahoo.co.uk (S. Thomas). http://dx.doi.org/10.1016/j.mser.2017.03.001 0927-796X/© 2017 Elsevier B.V. All rights reserved. Materials Science and Engineering R 116 (2017) 1–29 Contents lists available at ScienceDirect Materials Science and Engineering R journal homepage: www.elsevier.com/locate/mse r