W. Yang et al., MORPHOLOGICAL INVESTIGATIONS OF CROSS-LINKED POLYSTYRENE MICROSPHERESBY SEEDED POLYMERIZATION, Colloid and polymer science, 276(8), 1998, pp. 655-661
Crosslinked polystyrene microspheres with novel surface and inner morp
hologies were synthesized by seeded polymerization following a seed-sw
elling method, using uncrosslinked polystyrene microspheres as seeds a
nd a mixture of toluene, styrene (St), and divinylbenzene (DVB) as the
swelling agent. With the increasing toluene/(St + DVB) ratio, the cro
sslinked particles changed from smooth-surfaced spheres to deformed sp
heres with dimples or heavy dents at the surface. A single hole inside
the spherical particles was produced at low St/DVB ratio, while highe
r St/DVB ratios gave irregular dented or dimpled particles. Ultrathin
cross-section observation by TEM revealed a non-uniformly crosslinked
inner structure.