The present disclosure provides a polymeric composition resistant to temperatures comprising Poly 2,5rBenzimidazole having intrinsic viscosity (I.V.) between 1.0 and 2.5; and at least one binder having a glass transition temperature less than the glass transition temperature of Poly2,5-Benzimidazole and intrinsic viscosity ranging between 0.2 and 1.5. The present disclosure also provides a process for preparing the polymeric composition resistant to temperatures.

A chopper disc for a device for the processing of neutron beams is made of carbon fibers and has a concentric, hollow cylindrical recess for receiving a hub for connection to a pivot bearing. The chopper disc also includes a concentric absorber area for absorbing neutrons striking the chopper disc and at least one window in the absorber area through which neutrons of the neutron beam can pass. The carbon fibers extend from the outer periphery of the chopper disc radially in the direction of the recess and contact the recess tangentially.

Compression molded articles employing circumferential surfaces having friction-enhancing patterns to contact substrates during wet chemical processes are disclosed. An article such as an annular body may be formed by a compression molding technique. By including a patterned surface as part of an outer circumferential surface of the annular body, frictional contact between the annular body and the substrate may be enhanced as friction-reducing fluids associated with a wet chemical processes may be directed away from the desired friction contact area between the annular body and the substrate. In this manner, frictional contact may be enhanced and the substrate may be effectively positioned and moved during the wet chemical process to improve the effectively of the process.