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Multiwalled carbon nanotubes (MWNTs) were functionalized by oxidation with potassium permanganate using a phase transfer catalyst. The functionalized nanotubes (f-CNTs) were allowed to react with a functional chemical such as 3-methacryloxypropyltrimethoxysilane (3-MPTS). The f-CNTs and the reaction product of f-CNTs and 3-MPTS (fs-CNTs) were characterized by Fourier transform infrared and energy dispersion spectroscopy and also by scanning electron microscopy and transmission electron microscopy analysis. The MWNTs attached to the organofunctional moieties have a greater versatility for further utilization of nanotubes in different applications.

Two smart terpolymer gels, MS-1 and MS-2, were synthesized such that the same gel can respond to more than one external environmental condition, such as pH, temperature, solvent composition, electric field. So two terpolymers gels of vinyl monomers such as sodium acrylate, acrylamide and N -isopropyl acrylamide were synthesized by using ammonium persulfate (APS) as an initiator, N ,N ,N ,N -tetramethyl ethylene diamine (TMEDA) as an accelerator and methylene bisacrylamide as a cross-linker.These terpolymers were characterized by elemental and Fourier transform infrared analysis. The swelling behavior of these terpolymer smart gels was evaluated by changing the pH, temperature and solvent composition. The variation of the swelling behavior with time was evaluated in an aqueous medium at room temperature. The time taken for maximum swelling (t m ) was about 20 min for the gel MS-2. However the t m value for the gel MS-1 is higher than that of MS-2. The swelling behavior remains almost unchanged over a temperature range of 22-50 • C for both the gels. The discontinuous volume transitions were observed at pH 7.6 and 8.2 for the two gels, MS-1 and MS-2, respectively. The gel MS-1 suddenly shrinks below and swells above pH 7.6. Correspondingly, the pH is 8.2 for the case of MS-2. Volume transitions in an acetone-water mixture were also observed for these gels. The swelling behaviors of these two smart gels are almost parallel above the 40% acetone concentration.

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Low-density polyethylene (LDPE) film was chemically modified by chromic acid treatment to generate polar groups on the surface. The film samples were etched by chromic acid with variation of temperature at a constant time (30 min) and variation of time at a constant temperature (room temperature ϭ 26°C). The variation of weight and thickness of the film samples before and after etching was measured. The surface morphology of the etched films was studied by Scanning Electron Microscopy (SEM). IR and XPS analysis revealed the introduction of polar groups like OCOOH, ͘CAO, OSO 3 H on the etched LDPE film surface, which exhibited improved printability. Etching also enhanced adhesion with epoxy resin. The mechanical properties of the laminates of the two specimens of the same film sample with epoxy resin were also measured.