- Previous Article
- Next Article
- Table of Contents
Journal of Applied Polymer Science, Vol.92, No.3, 1375-1387, 2004
One-pot synthesis of polymeric bead bearing surface charge
Preparation of polymeric bead bearing surface charge was carried out by using one-pot suspension polymerization of styrene and divinylbenzene (DVB) in the presence of cationic functional monomer, 3-methacryloylamino) propyl trimethyl ammonium chloride (MAPTAC), by using K,SO, and AIBN as initiators. First, polymerization of MAPTAC in aqueous solution using K2S2O8 initiator was performed for the determined time to generate a PMAPTAC radical. Second, the mixture of styrene, DVB, and AIBN initiator was fed into the solution of PMAPTAC radicals and then allowed the polymerization to proceed for another specified time. During the stage of polymerization of styrene and DVB, incorporation of PMAPTAC radicals onto the bead surface took place, resulting in the final bead particle comprising two layers (from SEM results): the inner core of the poly(styrene-co-DVB) support and the outer layer of copolymerization adduct of styrene, DVB, and PMAPTAC radical revealed by FTIR analysis. Factors affecting particle size, size distribution, and surface functionality (PMAPTAC segment) were investigated. Of all synthetic parameters, types of surfactants and amounts of DVB were found to play an important role in controlling the particle size and the surface functionality, respectively. Nonionic surfactant (cetyl alcohol) tended to produce large particle size with a majority of the population falling in the range of 500-1800 mum. Replacement of nonionic surfactant with cationic surfactant (CTAB) resulted in better control of particle size and size distribution because of its effective electrostatic stabilizer. An increase in the amount of DVB led to smoother bead surface as a result of less availability of styrene on bead surface, reducing surface charge density. The results of dye adsorption isotherm further confirmed that the cationic functional group was incorporated into the outer shell of the polymer bead. (C) 2004 Wiley Periodicals, Inc.
Keywords:one-pot suspension polymerization;polymer bead;surface charge;anion exchange;dye adsorption