Polymer Nanomechanics Realized by Nano-palpation Atomic Force Microscope》

Prof. Ken Nakajima

Department of Chemical Science and Engineering， Tokyo Institute of Technology

时间: 11月1日（周三）上午10点

地点：英士楼201会议室

概要🧏🏿🪥：

Several novel atomic force microscope (AFM)-based nanomechanical analyses were employed to unveil the nature of the interfacial region existing between rubber matrix and nanofiller. The mechanical interface is not a thermodynamically definable phase but a kind of buffer layer that smoothly interconnects the boundary. Viscoelastic properties were successfully determined by two different methods. Nanorheology AFM offers nanoscale dynamic mechanical analysis (DMA) testing at the interface, where the segmental dynamics at the interface were recognized to be different from that of the rubber matrix. The method, because of the high rigidity of the AFM instrument, could realize a wide frequency range measurement without controlling the environmental temperature, without relying on time-temperature superposition principle, to easily acquire master curves. The second method based on the Johnson’s standard viscoelastic model was a simple extension of force mapping mode AFM but can now show viscoelastic maps; it could visualize the difference in viscosity between the matrix and interface. Any of the techniques or their combination may be useful in the rubber industry because a lot of industrial challenges pay attention to interface engineering such as the modification of the surface state of fillers, end-functionalized polymers.