Study On Kinetics Of Polymerization Of Styrene And It's Copolymerization Action With Existence Of Montmorillonite

Polymer nanocomposites are of a novel type of advanced composites, which have been studied for more than 30 years. In recent years, the main studies on polymer/montmorillonite (MMT) nanocomposites were focused on synthesis and characterization of nanocomposites. It is scarce that study on kinetics of polymerization be affected by MMT added into the system. The effect of MMT on polymerization of styrene and it's copolymerization action was researched in this paper.The organic-montmorillonite(OMMT) is prepared successfully by adopting ion interchange with hexadecyltrimethylammonium bromide as a intercalation agent. The result of modification and the state of intercalation of organic cation are characterized by means of FT-IR,TGA and XRD. XRD and TGA studies showed that the interplanar spacing of montmorillonite increased from 1.26nm to 2.10nm and CEC of montmorillonite is 101.2mmol/100gMMT.The affection of OMMT on bulk polymerization of styrene (St) was studied dilatometrically. The experiment results show that the bulk polymerization induction period and rates increase with the increasing OMMT content and the affection become greater when the initiator concentration decrease. By kinetic analysis, OMMT participates the radical initiation reaction of the chain. DSC, XRD and TGA studies showed that lower BPO concentration, larger interlayer distance and higher thermal decomposition resistance temperature were observed in the nanocomposite.In the low montmorillonite content range, the effects of NaMMT and OMMT on the emulsion polymerization of St were then investigated. The rates of emulsion polymerization in region II decrease with the increasing montmorillonite content. In added NaMMT system, theefficiency of initiator decreases in presence of montmorillonite plate, then polymerization rates decrease. But the emulsion polymerization in presence of OMMT was a multi-factor interacted process. XRD studies showed that the obtained PS/montmorillonite nanocomposites have exfoliated structure.The copolymerization of St with N-phenyl maleimide (PMI) in presence of montmorillonite was researched. It was found that the bulk and solution copolymerization rates increase to different extent and the overall apparent copolymerization energy decreases and the intensity of alternating copolymerization was enhanced. But the emulsion copolymerization rate decreases and no obvious change of the intensity of alternating copolymerization was observed. XRD studies showed that emulsion intercalation polymerization is more favor for the preparation of St-PMI/montmorillonite nanocomposites.