Direct observation of 890 ns dynamics of carbon black and polybutadiene in rubber materials using diffracted x-ray blinking

Abstract

Dynamic behavior in soft matter physics, biology, and nanoscience frequently occurs on submicrosecond timescales. Diffracted x-ray blinking (DXB) is a unique method that can provide a broad range of spatial scale information and is becoming an attractive tool for use at high repetition rate x-ray facilities. In this study, we performed DXB experiments with 890 ns time resolution at the European X-ray Free-Electron Laser Facility to obtain dynamic information about rubber samples that are typically used in automobile tires. Time-resolved scattering was simultaneously recorded for two samples that mainly consisted of carbon black (CB) and polybutadiene (PB). These samples contained either graphitized or non-graphitized CB and displayed significantly different dynamics. A clear interaction between CB and PB was observed, indicating that the mobility of PB was changed by the introduction of CB. Restricted polymer motion was observed in the q-range of 0.78–1.58 Å−1 regions. Our results suggest that the particle network can be flexibly controlled without impairing the mechanical strength of the rubber.