The present invention relates to thermoset and polyareneazole pulp for use as reinforcement material in products including for example fluid seals and friction materials, as a processing aid including its use as a thioxotrope, and as a filter material. The pulp comprises (a) irregularly shaped, thermoset fiber fibrous structures, (b) irregularly shaped, polyareneazole fibrous structures and (c) water whereby thermoset fiber fibrils and/or stalks are substantially entangled with polyareneazole fibrils and/or stalks. The invention further relates to processes for making such thermoset and polyareneazole pulp.