Phase separation in the synthesis of styrene–divinylbenzene copolymers with di‐2‐ethylhexyl phthalate as diluent

摘要

AbstractPhase separation by suspension copolymerization of styrene–divinylbenzene (DVB) with di‐2‐ethylhexyl phthalate (DOP) as diluent was investigated using equilibrium swelling, swelling rate, apparent densities, and mercury porosimetry. The copolymer prepared in the absence of DOP is heterogeneous, showing that a phase separation exists in the polymerization system, and, in the presence of DOP, the propagating copolymer separates earlier. Furthermore, with increasing amounts of DVB, phase separation occurs earlier than gelation, which causes a sudden increase in the amount of pores about 200–500 Å in diameter corresponding to the interstices between the micr