XPCS Study of Dynamic Strain Response of Rubber Nanocomposite Containing Functionalized Chains

Coupling agents are widely used in rubber nanocomposites to improve macroscopic properties for targeted applications. We have shown using In situ X-ray Photon Correlation Spectroscopy how the coupling agents change the filler nonequilibrium microdynamics response to dynamic strain. The incorporation of functionalized chains provides an additional means of modifying the filler-polymer interface to tailor properties. We present the microdynamics seen by XPCS for nanocomposites in which a fraction of lower molecular weight rubber chains are incorporated into the network as polymeric additives. The microdynamics differ for the case in which these short chain additives are end-functionalized and the case in which they are not functionalized. The macroscopic properties as measured with Dynamic Mechanical Analysis are considered in light of the insights into the nonequilibrium microdynamics provided by XPCS.



We thank CenTiRe for funding and Dynasol Group for sample preparation. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.