Preparation and Properties of Polyurethane/Epoxy Composites Modified with Graphite Nanosheets

The graphite nanosheets( GNS) modified polyurethane( PU) / epoxy resin( EP) composites were successfully prepared through sequential polymerization. The dispersion of GNS in composites was characterized by scanning electron microscope( SEM). The mechanical properties of composites show that the maximum of tensile strength and tensile modulus achieves to 60 MPa and 93. 1 MPa respectively when the addition of GNS is 0. 25%. Compared to the neat system,the tensile modulus and flexural strength of PU / EP composite with 4% GNS are increased by 73. 1%,and76. 1% respectively. With the introduction of modified GNS,the composites have higher Tgand wider damping temperature range than pure EP / PU composite. The maximum of damping temperature range is obtained at the modified GNS content of 2%.