Thermally robust highly crosslinked poly(methyl methacrylate-co-divinyl benzene) microspheres by precipitation polymerization

Abstract

We prepared thermally robust fully crosslinked poly(methyl methacrylate-co-divinyl benzene) [poly(MMAco-DVB)] microspheres successfully by precipitation polymerization in the absence of a stabilizing agent. The DVB concentration plays a pivotal role not only in the formation of the individually stable microspheres but also in the polymerization characteristics, including the particle size, the uniformity of size, the polymerization yield, and the thermal properties. The number-average diameter of the microspheres increased linearly, from 0.72 to 2.15 μm, and the particle size distribution became narrower, by elevating the uniformity from 1.35 to 1.12, as the DVB concentration increased from 20 to 75 mol%. In addition, the yield of the polymerization increased, from 73.4 to 98.6%, as the DVB concentration increased. Since the prepared particles possess fully crosslinked microstructures, no glass transition temperatures were observed, but all the samples prepared with DVB concentrations ranging from 20 to 75 mol% possess enhanced thermal properties. Based on the DSC and TGA data, the thermal stability of the microspheres prepared by the precipitation polymerization is significantly improved as a result of crosslinking with DVB.

Size and uniformity variation of poly(MMA-co-DVB) particles upon precipitation polymerization

“…19,20 Furthermore, we have reported the mechanism 21 of the precipitation polymerization based on the surface properties of the microspheres, and the comparison 22 with dispersion polymerization based on the variation of the final size with respect to the polymerization ingredients.…”

Synthesis of poly(acrylamide‐co‐divinylbenzene) microspheres by precipitation polymerization

“…[poly(MMA-co-DVB)], [20][21][22] and poly(styrene-co-divinylbenzene) [poly(St-co-DVB)]. 23 In addition, mechanistic studies to elucidate the formation of stable microspheres in the absence of any stabilizer have been reported 24,25 in which the absorption of oligomeric species onto the nuclei and the high degree of crosslinking are the primary reasons for the formation and stable growth of the microspheres.…”

“…28 In our previous studies, poly(St-co-DVB) and poly (MMA-co-DVB) microspheres containing various concentrations of divinylbenzene (DVB), from 5 to 75 mol %, were synthesized by precipitation polymerization, and their unexpected thermal properties, superior to those of crosslinked polymers prepared by emulsion and suspension polymerization, were found to be due to a fully crosslinked microstructure. 22,23 In this study, poly(acrylamide-co-divinylbenzene) [poly(AAm-co-DVB)] microspheres were prepared by precipitation polymerization, and the effects of DVB on the polymerization characteristics and size/uniformity of the microspheres were investigated.…”

Dispersion polymerization of styrene employing lyophilic comonomer in the absence of stabilizer: Synthesis of impurity-free microspheres

“…1 Such microspheres have been used in information technology, chromatographic separation, electric and electronic application, and biotechnology. [2][3][4] Recently, the monodisperse polymer particles have been applied to more advanced fields such as a template material for preparing three dimensionally ordered colloidal crystals.…”