A new high pressure cell with sapphire windows for small-angle neutron scattering

The design and the construction of a cell for the study of the conformation and the structure of liquid crystal polymers under pressure is complex because of the high viscosity of these materials and the use of an external magnetic field to achieve a macroscopic alignment. We have developed a system reaching 1500 bar at 420 K, completely amagnetic, including a small leakproof inner cell sample container with a flexible wall and a larger outer cell resistant to high pressure, with sapphire windows allowing a 8 mm diameter neutron beam aperture, with scattering angles up to 14°. This cell is also equipped with a double sample volume, in order to measure sample volume changes by a differential method.