Nanocomposites based on poly (n-butyl methacrylate) (PBMA) with various concentrations of titanium dioxide (TiO 2 ) nanoparticles were synthesised by in situ free radical polymerisation method. The formation of nanocomposite was characterised by FTIR, UV, XRD, DSC, TGA, impedance analyser and flame retardancy measurements. FTIR and UV spectrum ascertained the intermolecular interaction between nanoparticles and the polymer chain. The XRD studies indicated that the amorphous region of PBMA decreased with the increase in content of metal oxide nanoparticles. The SEM revealed the uniform dispersion of nanoparticles in the polymer composite. The DSC and TGA studies showed that the glass transition temperature and thermal stability of the nanocomposites were increased with the increase in the concentration of nanoparticles. The conductivity and dielectric properties of nanocomposites were higher than pure PBMA and the maximum electrical property was observed for the sample with 7 wt% TiO 2 . As the concentration of nanoparticles increased above 7 wt%, the electrical property of nanocomposite was decreased owing to the agglomeration of nanoparticles in the polymer. Nanoparticles could impart better flame retardancy to PBMA/TiO 2 composite and the flame resistance of the materials improved with the addition of nanoparticles in the polymer matrix.

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Novel nanocomposites based on chlorinated styrene butadiene rubber (Cl‐SBR) and manganous tungstate (MnWO4) nanoparticles have been developed using a simple and efficient open two roll mixing mill at room temperature. The nanocomposite containing varying loading of nanoparticles have been assessed for their spectral behavior, thermal, dielectric, flammability properties as well as the transport of aromatic solvents through their networks. Intermolecular interaction between the chlorinated moieties of SBR and MnWO4 has been revealed by Fourier transform infrared and UV‐Vis spectral studies. The uniform dispersion of nanoparticles and the crystalline peaks of MnWO4 nanoparticles in Cl‐SBR were observed from SEM and XRD, respectively. Thermogravimetric analysis and flame resistance analysis showed that the thermal stability and flame retardancy of Cl‐SBR increased with increasing ratio of MnWO4. The dielectric constant was much improved with the entire range of frequencies and the optimum dielectric constant was obtained for 7 phr loading. Transport parameters like the sorption, diffusion, and permeation coefficients were tabulated in terms of the nature of solvent, and the loading of nanoparticles. The solvent uptake reduced by the addition of nanoparticles up to 7 phr and thereafter the solvent uptake increases. The activation energy for the diffusion, sorption, and permeation process was evaluated and these values were highest in xylene at all filler loading. The mechanism of transport of the aromatic solvents through Cl‐SBR/MnWO4 nanocomposite was found to be anomalous mode. POLYM. COMPOS., 39:E1880–E1889, 2018. © 2018 Society of Plastics Engineers

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Using free radical polymerization process a series of samarium-doped titanium dioxide (Sm 3+ -doped TiO 2 ) nanoparticles containing poly (n-butyl methacrylate) (PBMA) composites were synthesized. The fabricated samples were characterized by XPS, FTIR, UV, XRD, DSC, TGA, flame retardancy studies, and impedance analyser. The shift in FTIR peak of the nanocomposites to higher wavenumber indicates the interfacial interaction between nanoparticles and PBMA. The UV spectra indicated that the metal oxide nanoparticles could enhances the interfacial interaction in the polymer composites. SEM images showed the uniform dispersion of nanoparticles into the macromolecular chain of PBMA. XRD patterns of the composites indicated the ordered arrangement of nanoparticles within the polymer and the regularity of the chain improved by the increase in concentration of nanoparticles. Better flame resistance and thermal stability were attained by the addition of nanoparticles. The flame retardancy and thermal stability of the composites were improved with the increase in concentration of Sm 3+ -doped TiO 2 . The glass transition temperatures of the composites were much enhanced by the increase in weight percentage of nano-filler. The AC conductivity, dielectric constant and dielectric loss tangent of the composites were higher than the pure PBMA and these properties enhanced with the loading of nanoparticles up to 7 wt.% and thereafter the values decreases.

The effect of zinc sulfide (ZnS) nanoparticles in chlorinated styrene‐butadiene rubber (Cl‐SBR) was analyzed by X‐ray diffraction analysis (XRD), scanning electron microscopy (SEM), Differential Scanning Calorimetry, and impedance analyzer. The cure time, mechanical properties, and solvent transport of petroleum fuels through the Cl‐SBR/ZnS nanocomposites at different temperatures were evaluated. XRD and SEM studies showed that ZnS nanoparticles were well‐placed in the polymeric structure of Cl‐SBR. The increased glass transition temperature of the composite with the loading of nanoparticles indicated the increased molecular rigidity. Rheometric torque, alternating current conductivity, dielectric property, tensile strength, tear resistance, modulus, hardness, abrasion resistance, heat build‐up, and compression set were increased with the loading of nanoparticles, however, cure and scorch time, elongation at break, and resilience were reduced with the loading of nanoparticles. The diffusion results have been explained in terms of the size of liquid molecules and the diffusion mechanism was found to follow the anomalous trend. The activation energy for diffusion, sorption and permeation process was evaluated. These activation energy parameters were increased with the size of the penetrant molecules and also with the loading of nanoparticles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46538.

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