Nanocomposites latex-based polystyrene

A benchmarking, with regard to the achieved electrical properties in these semi-crystalline materials, is performed against a well-described fully amorphous model system, i.e., latex-based polystyrene nanocomposites also prepared by latex technology, which were extensively reported in previous chapters of this book, as well as elsewhere. 

Transparent SWNT/insulating polymer nanocomposites have not been made with high conductivity values, mainly because of the intrinsic charge localization arising from insulating polymer dispersant. In a direct comparison, SWNTs were stabilized with insulating surfactant (SDS) or conductive poly(3,4-ethylenedioxythiophene) (PEDOT) PSS. " Both SWNT dispersions were introduced into a polystyrene matrix via a latex-based route. Composites with PEDOT PSS-stabilized SWNTs showed a percolation threshold of 0.18 wt% and a conductivity value of 500 S m compared with 3.8 wt% and 20 S m for the SDS-based composites, respectively. The authors attributed the conductivity enhancement to conduction bridge formed by the conductive polymer between adjacent SWNTs. 

The purpose of the present chapter is to illustrate with the presentation of some chosen examples how broadly the latex-based concept can be applied to all kinds of polymer systems. I n this respect, several composites were prepared with various polymer matrixes. Emphasis was put on the use of alternative continuous nanocomposite phases other than "single amorphous polymers such as poly [methyl methacrylate) [PMMA) and polystyrene [PS], which have already been reported in detail in Chapter 4. These alternative systems are... 

Many synthesis methods for nanopartides of these materials and thdr surface functionalization have been devdoped. Nanocomposites based on polyolefins were prepared by mdt compounding with nanoscaled ZnO and 1102. Amphiphilic copolymers and surfadants were used to stabilize pattides for film casting in polystyrene, " polycarbonate, and PMMA. By in situ partide preparation in MeOH and subsequent mixing with acetone and PMMA for solvent evaporation transparent ZnO/PMMA films could be realized even without further surface modification. Poly(acrylic add-co-sodium aaylate)/ZnO composite latex partides were obtained via inverse miniemulsion polymerization. ... 

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