Kim, Kyeongmin Nam, Ki-Ho Lee, Jaekwan Kim, Ho-Joong Goh, Munju Ku, Bon-Cheol You, Nam-Ho 2024-01-20T00:31:43Z 2024-01-20T00:31:43Z 2021-09-05 2017-10 0008-6223 https://pubs.kist.re.kr/handle/201004/122229 We report an effective method for fabricating graphene-based multifunctional polyimide (PI) nano-composites via in situ polymerization, by the chemical defect-healing of pyridine functionalized reduced graphene oxide (H-Py-RGO). H-Py-RGO was successfully obtained through intramolecular cross-dehydrogenative coupling (ICDC). The mechanical properties, and thermal stability of the PI/H-Py-RGO nanocomposites were significantly improved compared with those of pristine PI film due to the restoration of the defect sites on the graphene surface, and the resulting high compatibility between the H-Py-RGO and the PI matrix. The tensile strength and modulus of the PI/H-Py-RGO nanocomposites with 1 wt% of added H-Py-RGO were increased by about 598% (883.5 MPa) and 535% (39.4 GPa) compared to those of pristine PI, respectively. Furthermore, 5 wt% H-Py-RGO loading resulted in a 91% reduction in the coefficient of thermal expansion (CTE) of the PI/H-Py-RGO nanocomposite. (C) 2017 Elsevier Ltd. All rights reserved. English PERGAMON-ELSEVIER SCIENCE LTD THERMAL-PROPERTIES OXIDE COMPOSITES REDUCTION Effect of defect-healing in graphene nanosheets on the mechanical properties of polyimide nanocomposites Article 10.1016/j.carbon.2017.06.102 1 CARBON, v.122, pp.614 - 621 CARBON 122 614 621 scie scopus 000407394200066 2-s2.0-85021829501 Chemistry, Physical Materials Science, Multidisciplinary Chemistry Materials Science Article THERMAL-PROPERTIES OXIDE COMPOSITES REDUCTION Polyimide Defect-healing Reduced graphene oxide Mechanical properties Coefficient of thermal expansion