polymer bead

https://doi.org/10.1351/goldbook.14275
Sphere of polymer, usually with a diameter in the range from one-tenth to a few millimeters.
Source:
PAC, 2011, 83, 2229. (Terminology of polymers and polymerization processes in dispersed systems (IUPAC Recommendations 2011)) on page 2230 [Terms] [Paper]