Abstract: | A dynamic small-angle x-ray scattering system (DSAXS) for the study of materials deformation and relaxation has been developed in the National Center for Small-Angle Scattering Research, Oak Ridge National Laboratory (NCSASR-ORNL), in collaboration with Polymer Research Institute of the University of Massachusetts. The principles of DSAXS are outlined, including experimental procedures such as π-sector and Fourier expansion techniques. A few important functions required for studies of crystalline polymers, namely, static and dynamic lamellar orientation, dynamic lamellar separation, dynamic invariant function, etc., are defined. The hardware and software of the DSAXS system are described. Some preliminary results obtained for a spherulitic high-density polyethylene by π-sector technique and for a row-nucleated polybutene-1 by Fourier expansion techniques are demonstrated to evaluate the performance of the system. |