Description:
An apparatus has been developed which permits NMR measurements at somewhat higher pressures than was previously possible. It makes use of supported taper pistons of chrome oxide with pyrophyllite or boron nitride as the supporting material. With a sample 2 mm thick, pressures of 40 kbar are obtainable; with a sample 0.9–1.0 mm thick, pressures as high as 80–90 kbar may be possible. Data of line width vs pressure are presented for Teflon and polyethylene, and the effect of pressure on the structure of these materials is briefly discussed.