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Cure kinetic studies on nitrile rubber(NBR)-layered clay nanocomposites, prepared by a melt mixing process, was investigated using a cure rheometer and differential scanning calorimeter (DSC). The characterization of the structure of the nanocomposites of uncured and cured samples was performed using X-ray diffraction. The results showed that the interlayer spacing of cured nanocomposites was smaller than that of the uncured sample due to partial removal of organoclay from the interlayer spacing. The cure characterization showed a marked decrease in the scorch time of the NBR/organoclay system without affecting the optimum cure time and torque values due to the accelerating and plasticizing effect of organoclay. DSC analysis showed a reduction in cure time and increase in enthalpy of curing for the compounds added with organoclay. There was a little change in cure behavior of the NBR/unmodified clay system. NBR/clay nanocomposite showed the suitability of autocatalytic model for analyzing the cure parameters of rubber/clay nanocomposites. The activation energy of curing of NBR/O-MMT nanocomposites was lower than that of pristine NBR. The kinetic parameters determined from the model equation showed close fitting with the experimental results, indicating the suitability of autocatalytic model for cure characterization.

Polycaprolactone (PCL) nanofibers (PCL-NF) with uniform fibrous structure were fabricated by electrospinning. However, PCL-NF has hydrophobic surface, lacks functional groups and hence it is not a good substrate for cell adhesion. To improve the cell adhesion, PCL-NF surfaces were modified by low pressure RF discharge plasma treatment using monomer such as acrylic acid or oxygen gas. The plasma treated PCL-NFs improved the wettability and cell proliferation.

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Potassium iodide (KI) impregnated activated carbons were prepared and applied for the removal of hydrogen sulfide. The adsorption dynamics of the prepared adsorbents were investigated in fixed-bed column as functions of the concentration of hydrogen sulfide and oxygen, and relative humidity. It was found that the adsorption capacity was highly dependent on the oxygen concentration because of the chemical adsorption of hydrogen sulfide on KI impregnated activated carbon. The adsorbents before and after adsorption of hydrogen sulfide were characterized by BET, SEM and EDS analysis.