No abstract

No abstract

Mechanical and thermal properties of poly(vinyl chloride) (PVC)/nanoclay (NC) composites prepared via meltblending in a single-screw extruder were investigated. The effects of NC type, NC content, and K-value of PVC were evaluated by using L9 orthogonal array of the Taguchi approach. The most influential variables and significance of interactive effects were examined for the highest values of Young's modulus and hardness. Scanning electron micrographs and X-ray diffraction patterns revealed the formation of exfoliated/intercalated structures. Although the K-value has a minor individual effect on mechanical characteristics, the interaction of the K-value with NC type and NC content is significant. The composites were also characterized and tested by using analysis by thermal gravimetry, differential thermogravimetry, and differential scanning calorimetry methods. The results of the thermal studies indicated that decomposition of the organic modifier of NCs has a catalytic effect on the dehydrochlorination of PVC. This finding justifies the rather low mechanical properties of PVC/ organoclay nanocomposites. Fourier-transform infrared spectra of the samples were indicative of accelerated degradation reactions, which provided support for above observations.

A desulfurization process for model oil and real oil was investigated based on the chemical oxidation of mixed sulfur containing compounds in the presence of nitrogen compounds (indole and quinoline) using hydrogen peroxide as oxidizing agent and dodecamolibdophosphoric acid (H 3 PMo 12 O 40 ) encapsulated in a kind of metal-organic framework (HKUST-1) as PMo@HKUST-1. The effect of isopropanol, ethanol and acetonitrile as extractive solvent and 1-ring (toluene, xylene and mesitylene) and 2-ring (naphthalene) aromatic hydrocarbons in desulfurization of model oil was studied. The desulfurization of sulfur-containing compounds was accelerated in the presence of aromatic hydrocarbons. In fact, a higher desulfurization efficiency of the heterogeneous catalyst could be achieved with system containing a polar solvent in contact with an aromatic hydrocarbon. Quinoline had no effect on oxidative desulfurization (ODS) reaction, whereas indole had a slightly negative effect. Presence of aromatic compounds had slightly positive effect on ODS reaction.

No abstract