A process of manufacturing a composition comprises a particulate drag reducing agent is disclosed. The process comprising: continuously forming a temporary container; introducing an unsaturated monomer component and a radical polymerization component into the temporary container; sealing the temporary container to form a sealed temporary container; allowing the unsaturated monomer component to polymerize in the sealed temporary container to form the drag reducing agent via a radical polymerization reaction, the drag reducing agent having a molecular weight of about 1 million gram/mol to about 50 million gram/mol; and grinding the drag reducing agent to form a composition comprising a particulate drag reducing agent, the particulate drag reducing agent having a particle size of about 1 to about 1,500 microns.