| Popis: |
The scission site of polystyrene ([Mbar]w = 300,000; [Mbar]w/[Mbar]n = 1.14) in dilute toluene solution undergoing extensional flow was studied using gel permeation chromatography. Three chromatograms for midpoint scission, 66.7% midpoint and 33.3% quarter point scission, and random scission were matched to the chromatogram of the degraded solution. The result showed that the second of the three chromatograms fitted best, which certainly ruled out the possibility that the polymer chain was fully extended before scission and that weak linkage was the site of chain scission. |
