Effect of addition graphene to ethylene vinyl acetate and low‐density polyethylene

Abstract

Graphene (Gr) distribution in low‐density polyethylene (LDPE) and ethylene vinyl acetate (EVA) considerably increased thermal stability and mechanical properties of LDPE/Gr or EVA/Gr composites. Dynamic mechanical analysis (DMA) and strength testing machine were used to study mechanical properties. The high specific surface areas and superior properties of Gr improved thermal strength, storage modulus, and mechanical properties of composites. Outstanding distribution of Grs was accomplished and verified by atomic force microscopy. LDPE/Gr and EVA/Gr composites were characterized by transmission electron microscope (TEM), X‐ray diffraction, and thermogravimetric analyses to study the distribution morphology and thermal strength. Results display that the presence of filler does not create an alteration in the microscopic structure of polymers. Measurement of tensile properties shows that the tensile strength of composites contains Gr is significantly higher than similar values for pure EVA and LDPE. The DMA shows that the storage modulus of composites is much greater than that of pure EVA and LDPE. The thermal stability of the composite contains Gr is also considerably higher than that of pure EVA and LDPE. J. VINYL ADDIT. TECHNOL., 24:E177–E185, 2018. © 2018 Society of Plastics Engineers

Effect of graphene on thermal stability and mechanical properties of ethylene-vinyl acetate: a molecular dynamics simulation

“…From figures 7(b)-(d), with the addition of graphene, the yield strength and tensile strength of nanocomposites increase significantly. This trend has also been supported by the recent similar experiments by Sabet et al [26] and Tayebia et al [24]. That is, a small amount of graphene can limit the fluidity of the EVA chains, improve viscoelasticity and interfacial interaction, and increase the modulus and strength of the composite.…”

“…The main reason for the increase in T g is that the large interfacial area of graphene affects the behavior of the surrounding polymer matrix, the free movement of polymer chains is limited by graphene [11,51]. The recent experimental [5,26,29] and theoretical [42,52] results shows that the interaction between the polymer molecules and the embedded graphene can confine polymer chains and reduce the chain mobility. And the similar experimental results of the graphene/EVA system by Kuila et al [5] and Sabet et al [26] show that the good dispersion of graphene limits the segmentation motion of the EVA chains, and enhances the interaction between the graphene and the EVA chains, increasing the glass transition temperature of EVA.…”

“…That is, a small amount of graphene can limit the fluidity of the EVA chains, improve viscoelasticity and interfacial interaction, and increase the modulus and strength of the composite. Many studies have shown that dispersion and interfacial interaction between graphene and polymer matrix are two key factors for achieving performance enhancement [26,55,[61][62][63]. For one thing, the increase in tensile strength owes possibly to the tough between graphene and polar acetate groups in EVA [26,64].…”

“…Many studies have shown that dispersion and interfacial interaction between graphene and polymer matrix are two key factors for achieving performance enhancement [26,55,[61][62][63]. For one thing, the increase in tensile strength owes possibly to the tough between graphene and polar acetate groups in EVA [26,64]. For another, graphene has a large aspect ratio and specific surface area and its contact geometry is a two-dimensional surface, which leads to better transfer of interfacial stress between graphene and EVA, directly improving the mechanical adhesion of the interface [24,65,66].…”

“…Recently, some experimental results have also demonstrated that small amounts of graphene in the EVA matrix will improve the elastic modulus and the hardness of the polymer matrix [5,25,26]. However, theoretical studies on the internal mechanisms of the effects of graphene on the thermal stability and mechanical properties of EVA are very limited.…”