In situ preparation of PI/amino-functionalized graphene composites and their properties

Amino-functionalized graphene (GE-NH₂) was synthesized and characterized. A series of polyimide (PI)/GE-NH₂ nanocomposites were then prepared by in situ polymerization. The influence of GE-NH₂ content on mechanical properties and thermal stability of the as-prepared nanocomposites was investigated. It was found that the mechanical properties of the nanocomposites were enhanced with the increase of GE-NH₂ loading. When the content of GE-NH₂ was 0.5 wt%, the tensile strength of PI/GE-NH₂ nanocomposites was up to 125.43 MPa (38.84% higher than that of neat PI). The modulus of PI/GE-NH₂ was increased by 48.48%. The decomposition temperature at 5 wt% of weight loss for PI/GE-NH₂ nanocomposites with 1 wt% of GE-NH₂ was increased from 541 (neat PI) to 556C. The improvement of mechanical properties and the thermal stability of PI/GE-NH₂ nanocomposites were due to the strong chemical bond and interfacial interaction between GE-NH₂ and PI matrix.