Today's KNOWLEDGE Share : Enhanced flexural properties of aramid fiber/epoxy composites by graphene oxide

Today's KNOWLEDGE Share

Enhanced flexural properties of aramid fiber/epoxy composites by graphene oxide:

The reinforcing effect of graphene oxide (GO) in enhancing the flexural strength and flex modulus of aramid fiber (AF)/epoxy composites were investigated with GO-AFs at a weight fraction of 0.1-0.7%. The flexural strength and flexural modulus of the composite reached 87.16 MPa and 1054.7 MPa,respectively, which were about 21.19% and 40.86% higher than those of the pure epoxy resin. In addition, the flexural properties and interfacial shear strength (IFSS) of composite reinforced by GO-AFs were much higher than the composites reinforced by AFs due to GO improved the interfacial bonding between the fiber& matrix.

Graphene possesses many remarkable properties, including high Young’s modulus (1100 GPa),superior fracture strength (125 GPa),large surface area (2630 m2/g).Due to these excellent properties, graphene and its derivatives, in particular grapheneoxide (GO) ,have found interesting applications in nanocomposites.GO has been demonstrated as an ideal reinforcement of the fiber-matrix.Research work on polymer nanocomposites.It showed that incorporation of nanoscale fillers graphene,with low content into polymers can obtain good enhancements in mechanical and physical properties. directly added GO into epoxy resin,the results showed that the mechanical properties of GO/epoxy composite were improved effectively. Among them,the maximum flexural modulus and flexural strength reached 2.94 GPa and 130.46 MPa,which are about 10.11% and 14.67% higher than those of the pure epoxy resin,found that GO utilization is an effective approach for improving the flex properties of carbon fiber reinforced polymer composites.The enhancement can be attributed to the existence of GO,providing fiber with increased roughness and polarity, resulting in strong mechanical interlocking between the fiber and matrix.

In this work,GO modified the AF surface firstly, then enhanced the epoxy matrix with GO-AFs. Based on the mechanical interlock mechanism mentioned above to systematically examine the role of GO in improving the flexural properties and IFSS of the AF/epoxy composite.

Although pure aramid fibers can be used to reinforce epoxy resin, significantly improved flex strength, flex modulus and IFSS can be obtained by introducing GO to modify aramid fibers.

1.The flexural strength and flexural modulus of the GO-AFs/epoxy composite containing 0.1 wt% GO-AFs are 87.16 MPa and 1054.7 MPa,which are about 21.19% and 40.86% higher than those of the pure epoxy resin.

2.The flexural strength and flexural modulus of the AFs/epoxy composite containing 0.7 wt% AFs are 81.59 MPa and 816.51 MPa, respectively, which are about 13.54% and 9.05% higher than pure epoxy resin.

3.The IFSS value of GO-AFs/epoxy composite reaches 8.29 MPa, which is higher than that of untreated AF by 36.8%.

4. GO is an excellent potential modifier to modify AFs.

source: Yinqiu Wu ,Bolin Tang &team