The most important problems in preparing a nanocomposite of polymer and nano clay are:1-Differences in nature of polymer and nano clay; most polymers are hydrophobic while clay has hydrophilic nature
2- Nano particles with diameters of less than100 nm aggregate easily because of their extermely high specific surface energy.
Many works have been done to overcome the above problems (1-3). In this research in order to over come the above difficulties, polyvinyl alcohol (PVA) which is a hydrophilic material was grafted on copolymer of styrene-maleic anhydride (PVA-g-S/MA), in order to increase hydrophiles of polystyrene. The main product of the reaction , copolymer of styrene-maleic anhydride which is grafted on polyvinyl alcohol (PVA-g-S/MA), was characterized by 13C NMR spectroscopy (Fig 1). As it can be seen in figure 1, grafting was successfully done. Peaks related to polyvinyl alcohol were observed at 64.4525 to 68.4417 ppm and those related to copolymer of styrene-maleic anhydride were seen at 126.871, 128.583 and 173.989 ppm. Also ultrasound which is a powerful instrument was employed to disperse inorganic nano clay in to the terpolymer (PVA-g-S/MA). XRD experiments show that Ultrasonic irradiation was able to disperse nano clay inside the PVA-g-S/MA terpolymer. Nano clay shows peak at 7.29 (2è), while nanocomposite has no peak at this angle.
Conclusion: Nano composite of clay and PVA-g-S/MA has exfoliated structure.
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