The utilization of renewable resources for the preparation of new materials is an alternative option for reducing the high demand of fossil feedstocks. Vegetable oils are potential bioresources that are renewable and abundantly available. Triglyceride-based vegetable oils, such as soybean, jatropha, linseed, sunflower, palm, castor, nahar seed, and canola oil, are being considered as precursors in the production of polymers. In this article, we attempt to summarize advancements in processes and technologies for the synthesis of polymers from various kinds of vegetable oils. The advantages and disadvantages of these biobased polymers with respect to traditional monomer-based ones are also highlighted.

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Sulfonation of polymers is of great importance for the packaging industry mainly due to its effect on the alteration of surface functionality of polymer films. In this study we customized liquid phase sulfonation of low‐density polyethylene (LDPE) swelling the polymer by using a combination of polar and nonpolar solvents. Swollen polymer was treated with sulfuric acid of varying concentrations with continuous mixing for in‐depth sulfonation of the polymer. Presence of cyclohexane and ethanol, as polar and nonpolar reagents, not only kept the batch under isothermal conditions but also homogenously influenced in‐depth functionalization of LDPE. The durability of the sulfonated polymer was determined by grinding the test samples 30 days after the reaction. Fourier transform‐infrared spectroscopy indicated presence of functional group moieties, which is also supported by increase of 5% and 1.35% in density and sulfur contents of the polymer, respectively. Contact angle measurements indicate 30° decrease in values of the sulfonated polymer which corresponds with decrease in carbon to hydrogen ratio (from 5.9 to 5.3) and increase in sulfur to carbon ratio (up to 0.0184) resulting from the sulfonation of the polymer. Differential scanning calorimetery results indicate almost linear reduction in the crystallinity of LDPE with an increase in acid concentration used for the sulfonation reaction. POLYM. ENG. SCI., 54:2522–2530, 2014. © 2013 Society of Plastics Engineers

a Carbon fibers were synthesized using a low-cost, economical method. Fresh rubber wood fibers (Hevea brasiliensis) were burned using a furnace in an inert condition at 350 to 450 o C for 2-4 hours, and after that the fibers were ground at 18000 rpm for 20 to 40 seconds. The effect of carbon fibers as a reinforcement agent on mechanical, physical, and morphological properties was investigated. In the composite preparation, carbon fiber dosages (0, 0.1, 0.25, and 0.5 wt.%) were used as variable factors, along with a urea formaldehyde content of 10%. The morphology of the specimens was characterized using X-ray diffraction (XRD), Thermogravimetric analysis (TGA), and Field Emission Scanning Electron Microscopy (FESEM). The mechanical tests indicated that when carbon fibers were added, the modulus of rupture (MOR) and internal bonding strength (IB) improved significantly. From the TGA graph it was observed that the thermal stability of the composites based on carbon fiber was higher than composites without it. The thermocouple readings showed that at a higher loading of carbon, the core temperature of the board increased faster than for the control board.

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