Nanocomposites from Other Waste Polymers

A superabsorbent nanocomposite based on partially neutralised acrylic acid, recycled PS foam and Na-MMT was prepared via emulsion polymerisation [65]. The results indicated that the acrylic acid monomer had successfully grafted onto the PS chains and the layers of Na-MMT were exfoliated after copolymerisation. Moreover, the addition of Na-MMT not only improved the thermal stability of the samples, but also increased the content and rate of water absorbency. 

In addition, the recycled expanded polystyrene and TiOi were mixed via the solution method [67] the transmission electron microscopy images indicated that the nanocomposites had an average particle size of 6-12 nm. The nanocomposite samples had greater polymer stability and higher discoloration efficiency for aqueous methylene blue solutions, due to the incorporation of TiOi nanoparticles. 

The addition of small amounts of commercial organoclays (Cloisite 15A and 30B) to recycled polycarbonate (rPC) was evaluated [70]. The results showed that the effect of the nanoclays on polymer degradation during the fabrication process depends on the amount of clay and the chemical nature of the organic modification. It was demonstrated that when small amounts of the appropriate clay are used, polymer 

Mahanta and co-workers [71] prepared a blend of rPC, recycled acrylonitrile-butadiene-styrene (rABS) and nanoclay, Cloisite SOB or Cloisite 15A. The blend was compatibilised with both PP-g-MA and solid epoxy resin. The mechanical properties of the rABS/rPC blend without a compatibiliser decreased in comparison to neat matrices. However, upon the addition of 5 wt% of a PP-g-MA compatibiliser, the mechanical properties improved. Similarly, further addition of the epoxy led to a synergistic behaviour in mechanical performance, particularly the modulus and tensile strength. Also, a greater improvement of the modulus was achieved in the rPC-rich blend by simultaneously adding two nanoclays. The thermal stability of the blends compatibilised with PP-g-MA and epoxy exhibited positive thermal properties. 

Martin and co-workers [68] also studied the nanocomposites of recycled PMMA with both natural and organically modified MMT. They reported that the tensile modulus increased upon increasing the content of both nanoclays, which resulted in nanocomposites with attractive mechanical, transparency and thermal properties. 

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