TIME-RESOLVED X-RAY-DIFFRACTION STUDIES OF STRUCTURAL TRANSITIONS IN ORGANIC POLYMERS USING SYNCHROTRON-RADIATION

The high brilliance of the Daresbury Synchrotron Radiation Source has been exploited in time-resolved x-ray fibre diffraction of changes in polymer conformation and organisation in response to patterns of mecha nical and thermal stress similar to those followed during industrial p rocessing. This has involved the development of a new x-ray camera whi ch can be used in both wide and small angle diffraction and allows uni axial drawing for draw rates up to 72,000% per minute (i.e. an increas e in length by a factor of 720 in one minute) at temperatures from amb ient to 400 degrees C. The use of electronic area detectors which disp lay the diffraction pattern while it is recorded allow experiments to be conducted in real-time. The variation in the diffraction is recorde d as a series of frames. The time to record a frame can be as short as 40 msecs.