Faculty Publications

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    Thermal degradation and swelling of thermoplastic vulcanizates from NBR/SAN and NBR/Scrap computer plastics blends
    (Huthig GmbH, 2009) Anandhan, S.; Rajeev, R.S.; De, S.K.; Bhowmick, A.K.
    Thermoplastic elastomeric blends of nitrile rubber (NBR)/poly(styrene- coacrylonitrile) (SAN) and NBR/scrap computer plastics (SCP) based on acrylonitrile-butadiene-styrene terpolymer (ABS) were prepared. Thermoplastic elastomeric blends of NBR/SAN containing various amounts of a model waste nitrile rubber powder (w-NBR) were also prepared. Thermogravimetric analysis of the above blends was performed in a nitrogen atmosphere. Both Friedman and Flynn-Wall-Ozawa methods were used for the evaluation of activation energies of thermal degradation of these blends. The dynamically vulcanised blends exhibit higher amount of activation energies for thermal degradation than the unvulcanised ones. Swelling studies were performed in various solvents having different solubility parameter values and maximum swelling was found to occur in a solvent having a solubility parameter that was closer to that of the blend components, i.e., around 20MPa1/2. Dynamically vulcan-ised blends show excellent resistance to IRM #903 oil as well as four chosen solvents possessing different solubility parameters (E).
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    Extruded poly(ethylene-co-octene)/fly ash composites - Value added products from an environmental pollutant
    (Kluwer Academic Publishers, 2012) Anandhan, S.; Sundar, S.M.; Senthil, T.; Mahendran, A.R.; Shibulal, G.S.
    Fly ash (FA) is a by-product generated during combustion of coal and has caused serious environmental concerns. In an effort to utilize FA beneficially, we developed composites from an ethylene-octene random copolymer (EOC) and unmodified as well as surfacemodified class-F fly ash (MFA) by twin screw extrusion. Addition of 20 wt% of MFA to EOC improves its tensile strength by 150%; also, MFA improves stress at 100% and 300% strains (M100 and M300) of EOC. Thermal stability of EOC matrix is appreciably improved by the addition of either FA or MFA, while the melting behavior is not appreciably influenced by either. Fractography study reveals an improved adhesion between the EOC and MFA particles up to a filler loading of 20%, beyond which the adhesion between EOC and MFA is weakened causing a reduction in mechanical properties. The 'flammable' nature of EOC changes to 'self extinguishing' on addition of even 10 wt% of FA or MFA, as found out from LOI study. © Springer Science+Business Media B.V. 2012.
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    Thermoplastic vulcanizates from post consumer computer plastics/nitrile rubber blends by dynamic vulcanization
    (Springer Japan, 2013) Anandhan, S.; Bhowmick, A.K.
    Due to depletion of natural resources and increasing greenhouse emissions, new technologies for the transformation of waste polymers into valuable materials represent one of our greatest current needs. Acrylonitrile-butadiene-styrene terpolymer (ABS) is one of the most widely used engineering plastics and is used as outer casing for electronic equipment. Nitrile rubber (NBR) is used in many applications that demand oil resistance. In an attempt to explore whether these materials can be successfully recycled, we prepared blends of scrap computer plastics (SCP) based on ABS with NBR and waste NBR powder (w-NBR), and investigated their mechanical properties and recyclability. Specifically, we assessed the effect of dynamic vulcanization and replacement of virgin NBR with w-NBR on the properties of 60/40, 70/30, and 80/20 NBR/SCP blends. These blends exhibited thermoplastic elastomeric behavior. The thermoplastic elastomeric blends showed excellent swelling resistance to standard lubricant oil (namely, IRM 903 oil). © 2013 Springer Japan.
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    Organoclay enabled nanofiber formation from a polyolefin elastomer
    (John Wiley and Sons Inc. P.O.Box 18667 Newark NJ 07191-8667, 2018) Kumar, B.; Prakrthi, A.N.; Senthil, T.; Bhat, K.; Anandhan, S.
    The solution electrospinning of polyolefins has not been deeply studied mainly due to the difficulty in dissolving these polymers in appropriate solvents. In this study, composite nanofibers of organically modified montmorillonite/ethylene-octene random copolymer were produced for the first time with a mixture of cyclohexane and xylene as a solvent by solution electrospinning. Montmorillonite was used as an additive to increase the electrical charge density of the polymer solution. The influence of solution and process parameters on the electrospun ethylene-octene copolymer fibers' morphology and diameter was investigated using the design of experiment. Multiple regression analysis was used for the optimization of the electrospinning parameters. Ultrafine fibers, with diameters in the range of 150–350 nm were obtained; these nanofibers exhibited an excellent hydrophobicity over a period of 10 min as revealed by contact angle measurements. © 2016 Wiley Periodicals, Inc.