Page 676 - Polymer-based Nanocomposites for Energy and Environmental Applications

Green polymer nanocomposites and their environmental applications 621

Fig. 23.3 Aggregated structure.

23.2.3 Emulsion polymerization
In this method, monomers (styrene and methacrylic acid) are dispersed in water along
with the emulsifier and different concentrations of silicates [6]. After the polymeriza-
tion process, a nanocomposite is formed in the way that a part of silicate is embedded
inside the polymer and a part is adsorbed on the particle surface.

23.2.4 In situ polymerization
In this method, firstly, the filler is swelled in the liquid monomer or monomer solution
because low-molecular-weight monomers seep in between the interlayers [6]. After
that, polymerization of monomers takes place in between the interlayers to produce
intercalated or exfoliated nanocomposites. This method is used for the preparation
of thermoplastics and thermoset-based composites [9]. This method allows the
grafting of polymer on filler surface that can improve the properties of final compos-
ite. The partially exfoliated structure can also be obtained by this method because of
the good dispersion and intercalation of fillers in the polymer matrix. As stated by
Abedi and Abdouss [10], it is the most suitable preparation method for the polyolefin/
clay nanocomposites because of the lack of rigorous thermodynamic requirement.

23.2.5 Template synthesis

This is also known as sol-gel technology. This method involved the formation of inor-
ganic filler in an aqueous solution or gel containing the polymer or the filler building
blocks [6,7,9-11]. The polymer promotes the growth of the inorganic filler crystals
and also serves as a nucleating agent. The nanocomposites are formed with the growth