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[Display omitted] • Thermal polymerization of divinylbenzene is studied by theoretical calculations. • Each polymerization step has high selectivity for para-divinylbenzene. • The polymerization of para-divinylbenzene is more favorable thermodynamically. • The polymerization rate of para-divinylbenzene is faster than other monomers. • The fastest consumption rate of para-divinylbenzene was observed in experiments. To understand the thermal self-initiated polymerization of vinyl monomers during the divinylbenzene refining process, the differences in reaction behavior among these monomers were studied by density functional theory calculations. The calculations reveal that para-divinylbenzene (para-DVB) exhibits higher reactivity than other monomers in polymerization. Specifically, among the first step of initiation which is a Diels-Alder reaction, the reaction between para-DVB molecules shows the lowest activation energy (Ea) of 134.6 kJ/mol. Subsequently, para-DVB preferentially undergoes molecule-assisted homolysis with the products of the aforementioned Diels-Alder reaction and formatting free radicals with an Ea of 74.8 kJ/mol and a reaction rate constant (k TST) of 3.48 × 10−3 L/mol∙s. In the propagation stage, para-DVB also exhibits the highest monomer reactivity, with a k TST approximately 1.4–2.25 times greater than other monomers. The polymerization preformed under refining conditions confirms that the consumption of para-DVB is faster than that of other monomers, consistent with the DFT calculations. [ABSTRACT FROM AUTHOR]

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Branched poly (styrene- co-acrylonitrile) was prepared by atom transfer radical polymerisation (ATRP) of styrene (St) and acrylonitrile (AN) with the feed composition of 0·5 using β-bromoethyl benzene (BEB) as the initiator and divinylbenzene (DVB) as the branching agent. The polymerisation kinetics and the development of branching were studied by gas chromatography (GC), triple detection size exclusion chromatography (TD-SEC) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The primary chains with the pendent vinyl groups were formed dominantly at a monomer conversion of less than 50%. The pendent vinyl group participated in the polymerisation, which resulted in the formation of branching structure accompanied by a rapid increase in molecular weight and a broadening in its distribution. The branching chains developed gradually as the molecular weight increased. The copolymers of higher molecular weights had higher branching degree than those of lower molecular weights. [ABSTRACT FROM AUTHOR]

Poly(styrene-co-divinylbenzene)/organic montmorillonite (OMMT) nanocomposites were prepared by suspension polymerization. OMMT was prepared by ion exchange method between sodium montmorillonite (SMMT) and cetyltrimethyl ammonium bromide (CTAB) in an aqueous solution. The character and structure of OMMT was revealed by XRD and FT-IR. The microstructure of polymer/OMMT nanocomposites was characterized by XRD, TEM and SEM. The thermal stability of polymer/OMMT nanocomposites was studied by TG and DTG. Also the effect of the amount of OMMT and divinylbenzene (DVB) on the thermal stability of polymer/OMMT nanocomposites has been discussed in this paper. It was observed that the crosslinked polymer/clay nanocomposites exhibited better thermal stability than pure polystyrene and polystyrene/clay nanocomposites under the experimental conditions. [ABSTRACT FROM AUTHOR]