The cross-linked poly(divinylbenzene) [PDVB] particles were synthesized in the presence of poly-(styrene-block-4-vinylpyridine) [P(S-b-4VP)] copolymer in aqueous media at 70 degrees C. The block copolymer consisting of the RAFT agent is used as an emulsifier and reactive stabilizer as well. The mechanism of the formation and growth of the cross-linked PDVB microspheres using the block copolymer was proposed on the basis of the evidence shown by the formation of micelles, morphology and internal structure of the particles, particle size and distribution, and the content of nitrogen on the particle surface. The block copolymer formed micelles with DVB in ethanol and water due to the amphiphilic character. When the polymerization is taking place inside the micelles and at the living site of the block copolymer, the growing poly(4-vinylpyridine) [P4VP] block propagates by the addition of DVB, and the chemical bonding of DVB occurs in the P(S-b-4VP) block copolymer. As a result, the P(S-b-4VP-b-DVB) triblock copolymer is formed, inducing tiny small particles. The tiny small particles having the living character due to the diblock and triblock copolymers are enlarged by chemical bonding and coagulation showing the coretex-like macropores of the particle surface and become smoother upon filling with the DVB oligomers.