High‐yield water‐phase exfoliated few‐defect graphene for high performance polymer nanocomposites

Abstract

Application of graphene requires a high‐yield, low‐cost, scalable production method, but it remains highly challenging. We here report a water‐phase technique to produce few‐defect graphene nanosheets (FGS) with a high exfoliation yield (92%), based on the chemically expanded graphite with ultrahigh specific surface areas, and demonstrate the application in graphene‐polymer nanocomposites. The exfoliated FGS has low degree of oxidation and preserves good mechanical and electrical properties, revealing promising potential for improving comprehensive properties of polymer composites. When 0.5 wt% FGS was incorporated to poly(methyl methacrylate) (PMMA), the 5% weight loss temperature and storage modulus increase by 87°C and 21%, respectively, relative to the neat polymer. With increasing the content of FGS to 4.6 wt%, the glass transition temperature of the composite increases by 25°C. In addition, the composites show a percolation threshold as low as 0.25 vol% and excellent electrical conductivity (50 S/m for 2.7 vol% FGS‐PMMA composite).

Manufacturing Technologies of Polymer Composites—A Review

“…After some new polymer composites have been developed, their mechanical properties, electrical conductivity and thermal conductivity have been properly controlled. It has also been widely used in electrode devices [ 21 , 22 ], electromagnetic interference (EMI) shielding devices [ 23 , 24 , 25 , 26 ], sensors [ 24 , 27 , 28 ], packaging materials [ 28 ] and energy storage devices [ 29 ].…”

Chemically expanded graphite-based ultra-high molecular weight polyethylene nanocomposites with enhanced mechanical properties

“…The expanded graphite lamella provide an open structure allowing for efficient exfoliation under mild conditions, while the low degree of oxidation prevents the extensive introduction of lattice defects [9]. In more recent, Wang and coauthors [10] used a surfactant to obtain stable CEG dispersions in water. Without surfactant, the dispersion proved to be difficult due to the low oxygen content of CEG, making it hydrophobic.…”