Interfacial Properties between Carbon Nanomaterials and Polymer Matrices

Nanomaterials, including nanoparticle, carbon nanotube and graphene, normally perform outstanding mechanical and other physical properties in nanoscale. However, how to improve the performance of their macroscale counterparts which are constructed by these nanoscale building-blocks is still a big challenge by using current formulation methodologies. One crucial issue is interfacial performance, where there are orders of magnitude more interfacial area created per volume of nano-fillers added and the high stiffness of graphene and carbon nanotube make such mismatch more distinctive. Herein, we have developed several experimental techniques in order to understand better the interfacial performance in nanoscale, which include a micro-cantilever test and a pressurized blister test. Firstly, we reported a study on the interfacial stress transfer between a monolayer graphene and a commonly poly(methyl methacrylate) matrix under pristine and modified interfacial interactions. We identify several key interfacial parameters including interfacial (shear) stiffness, strength and frictional stress for both graphene-based van de W and H-bonding nano-interface with the aid of in situ Raman spectroscopy measurements. Then, the adhesion energy for these two types of graphene interfaces is calculated on the basis of frictional behavior induced buckles afterrelease. Secondly, a pressurized blister test was utilized to apply deformation to mono/bilayer graphene. In situ Raman spectroscopy and atomic force microscope were employed to measure the strain map and out-of-plane deformation of the graphene in order to analyze the critical parameters for interlayer friction behavior. We further conduct physicsbased, experimentally calibrated theoretical models and numerical simulations to understand the interlayer behavior of multilayer graphene, including constitutive equation, failure models as well as mechanical parameters. We believe that the interfacial parameters presented in this study can develop valuable basis for interfacial optimal design of highperformance graphene-based nanocomposites

Keywords:

Polymer nanocomposites , interfacial property , carbon nanotube , graphene , Raman spectroscopy , pressurized blister test