Nanocomposites enhanced with two-dimensional, layered graphene fillers are a new class of engineering materials that exhibit superior properties and characteristics to composites with conventional fillers.However, the...Nanocomposites enhanced with two-dimensional, layered graphene fillers are a new class of engineering materials that exhibit superior properties and characteristics to composites with conventional fillers.However, the roles of ＂interlayers＂ in layered graphene fillers have yet to be fully explored. This paper examines the effect of interlayers on mechanical properties of layered graphene polymer composites.As an effective filler, the fundamental properties（in-plane Young＇s modulus E（L1）, out-of-plane Young＇s modulus E（L2）; shear modulus G（L12）, major Poisson＇s ratio V（L12）） of the layered graphene were computed by using the Arridge＇s lamellar model. The effects of interlayers on effective moduli of layered graphene epoxy composites were examined through the Tandon-Weng model. The properties of the interlayer show noticeable impact on elastic properties of the composites, particular the out-of-plane properties（Young＇s modulus E2 and shear modulus G（12））. The interlayer spacing is seen to have much great influence on properties of the composites. As the interlayer spacing increases from 0.34 nm to 2 nm, all elastic properties of the composites have been greatly decreased.展开更多
Understanding the roles of interlayers in reinforcement efficiencies by layered graphene is very important in order to produce strong and light graphene based nanocomposites. The present paper uses the finite element ...Understanding the roles of interlayers in reinforcement efficiencies by layered graphene is very important in order to produce strong and light graphene based nanocomposites. The present paper uses the finite element method to evaluate the interfacial strain transfers and reinforcement efficiencies in layered graphene-polymer composites. Results indicate that the presence of compliant interlayers in layered graphene plays significant roles in the transfers of strain/stress from matrix to graphene and subsequently the reinforcement effectiveness of layered graphene. In general, the magnitude of shear strain transferred onto the rigid graphene decreases as the thickness of the interlayer increases. This trend becomes insignificant as the graphene becomes sufficiently large(s>25,000). The shear strain at the interface of graphene-matrix is also greatly influenced by the interlayer modulus. A stiffer interlayer would result in a higher shear strain transferred on the graphene. The performance of the interlayers is further affected by the property of the composite and the architecture of the layered graphene stack. If a composite contains more graphene phase, the efficiency of reinforcement by a layered graphene becomes improved. If a graphene stack contains more interlayers, the effectiveness of reinforcement at the edges of the graphene becomes negatively affected.展开更多
基金supported by NASA Kentucky under NASA award No.:NNX15AR69H
文摘Nanocomposites enhanced with two-dimensional, layered graphene fillers are a new class of engineering materials that exhibit superior properties and characteristics to composites with conventional fillers.However, the roles of ＂interlayers＂ in layered graphene fillers have yet to be fully explored. This paper examines the effect of interlayers on mechanical properties of layered graphene polymer composites.As an effective filler, the fundamental properties（in-plane Young＇s modulus E（L1）, out-of-plane Young＇s modulus E（L2）; shear modulus G（L12）, major Poisson＇s ratio V（L12）） of the layered graphene were computed by using the Arridge＇s lamellar model. The effects of interlayers on effective moduli of layered graphene epoxy composites were examined through the Tandon-Weng model. The properties of the interlayer show noticeable impact on elastic properties of the composites, particular the out-of-plane properties（Young＇s modulus E2 and shear modulus G（12））. The interlayer spacing is seen to have much great influence on properties of the composites. As the interlayer spacing increases from 0.34 nm to 2 nm, all elastic properties of the composites have been greatly decreased.
基金supported by NASA Kentucky under NASA award No.:NNX15AR69H
文摘Understanding the roles of interlayers in reinforcement efficiencies by layered graphene is very important in order to produce strong and light graphene based nanocomposites. The present paper uses the finite element method to evaluate the interfacial strain transfers and reinforcement efficiencies in layered graphene-polymer composites. Results indicate that the presence of compliant interlayers in layered graphene plays significant roles in the transfers of strain/stress from matrix to graphene and subsequently the reinforcement effectiveness of layered graphene. In general, the magnitude of shear strain transferred onto the rigid graphene decreases as the thickness of the interlayer increases. This trend becomes insignificant as the graphene becomes sufficiently large(s>25,000). The shear strain at the interface of graphene-matrix is also greatly influenced by the interlayer modulus. A stiffer interlayer would result in a higher shear strain transferred on the graphene. The performance of the interlayers is further affected by the property of the composite and the architecture of the layered graphene stack. If a composite contains more graphene phase, the efficiency of reinforcement by a layered graphene becomes improved. If a graphene stack contains more interlayers, the effectiveness of reinforcement at the edges of the graphene becomes negatively affected.
