Synthesis and Characterization of PMMA Nanocomposites by Suspension and Emulsion Polymerization

Abstract

PMMA-layered silicate nanocomposites were prepared by in-situ suspension polymerization and emulsion polymerization. For the suspension polymerization, the silicate layers were dispersed individually in water, and we speculate that they are adsorbed on the surface of monomer droplets. For the emulsion polymerization, the nanocomposite was obtained by adding an aqueous dispersion of layered silicate into the polymer emulsion. Wide-angle X-ray diffraction (WAXD) and atom force microscopy (AFM) were used to characterize the structures of the nanocomposites. Analysis of samples from emulsion and suspension polymerization was consistent with an exfoliated structure; after melt pressing, WAXD analysis indicated that both intercalated and exfoliated structures were observed. The exfoliated structure was preserved when organic modifiers that produced tethered polymer chains were used. Compared to a PMMA macrocomposite, the nanocomposites prepared by these methods display glass transition temperatures that are up to 15 °C higher and thermal degradation temperatures that are up to 60 °C higher.

An experimental study of dynamic behaviour of graphite–polycarbonatediol polyurethane composites for protective coatings

“…This can be associated with the reduction of molecular mobility of the polyurethane chains imposed by the EG particles. That is a fraction of polymer could be immobilized on the surface of the EG particles [21,22,23,24,25,26,27]. The temperature range of the glass transition (T 2 − T 1 ), which is a measure of the sample heterogeneity [18], does not show a clear trend with the composition.…”

A review on the role of interface in mechanical, thermal, and electrical properties of polymer composites

“…For different polymer nanocomposites, T g was shown to be increased [206,207], decreased [180,208], or even unaffected [182,209] by the introduction of fillers into the system. More studies are summarized in Table 2.…”

Melt-Processable Nanocomposites Grafting-From Platelet Surfaces by Vapor-Assisted Surface Polymerization

“…Melt processing of plastics is an indispensable process for producing various moldings. It is known that exfoliated silicate platelets reaggregate to return to layered structures after melt processing has completed [32]. To inhibit the return to the layered structure, copolymerizable methacryloyloxyhexylammonium (C6) moieties were introduced on the silicate layer surfaces.…”