Not every material that is fine in air is fine in oxygen. Some metals keep burning in pure oxygen at pressures well below cylinder pressure, and many seals and lubricants ignite at temperatures a fast-opening valve can reach.
The two tables show how common alloys and polymers fare in oxygen service. Sort either one by any column and pick which column the chart shows. For alloys that is heat of combustion, lowest burn pressure and thermal conductivity; for polymers, oxygen index, auto-ignition temperature, heat of combustion and an acceptability index worked out from those three.