Polystyrene -polyethylene characterization data

The interpretation of diffraction data on amorphous polymers is currently a subject of debate. Ovchinnikov et al. (31,34) interpreted their electron diffraction data to show considerable order in the bulk amorphous state, even for polyethylene. Miller and co-workers (3536) found that spacings increase with the size of the side groups, supporting the idea of local order in amorphous polymers. Fischer et al. (32), on the other hand, found that little or no order fits their data best. Schubach et al. (37) take an intermediate position, finding that they were able to characterize first- and second-neighbor spacings for polystyrene and polycarbonate, but no further. 

In addition to this, extensional flow data (where available) are useful for polymer characterization and quality control, since these data are often sensitive to subtle changes in the chemical structure of the polymer. It should not be very surprising that the materials whose extensional properties have been studied most extensively are commodity thermoplastics like polyethylene and polystyrene. 

In this section we will describe the results of our angular dependent XPS measurements, XPS (0), which were made on a series of polystyrene (PS)-polyethylene oxide (PEO) diblock (PS-PEO) and triblock (PEO-PS-PEO) copolymers. Table 3 contains the copolymer composition and molecular weight data for the various block copolymers employed in this study. The synthesis, purification and characterization of these materials has been described previously. (H)... 

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