Novel natural composite films as packaging materials with enhanced properties.

The present work was devoted to prepare novel natural composite films based on carboxymethyl cellulose (CMC), gelatin and/or shellac. Four composites films series were prepared by altering the film compositions from CMC and gelatin or shellac. The composite films were prepared by solution casting in presence of glycerol (30% weight). Films were characterized by SEM, air permeability (porosity), tensile strength, burst strength, TGA and WVP. Antimicrobial activity in opposition to E. coli, B. mycoides and C. albicans were also investigated. The results revealed that, films exhibit flexibility with good antimicrobial, tensile strength, homogeneity, transparency, elongation properties, reduce porosity & air permeability and without signs of particles aggregation. Gelatin/CMC (50/50%) film was the most important one with respect to thermal stability, which exhibit a high thermal stability up to 800 °C. This study opens the door to use cellulosic composite materials to produce environmentally friendly, low-cost and sustainable packaging materials.

Production of ethoxylated fatty acids derived from Jatropha non-edible oil as a nonionic fat-liquoring agent.

Natural fatty derivatives (oleochemicals) have been used as intermediate materials in several industries replacing the harmful and expensive petrochemicals. Fatty ethoxylates are one of these natural fatty derivatives. In the present work Jatropha fatty acids were derived from the non edible Jatropha oil and used as the fat source precursor. The ethoxylation process was carried out on the derived fatty acids using a conventional cheap catalyst (K2CO3) in order to obtain economically and naturally valuable non-ionic surfactants. Ethoxylation reaction was proceeded using ethylene oxide gas in the presence of 1 or 2% K2CO3 catalyst at 120 and 145°C for 5, 8 and 12 hours. The prepared products were evaluated for their chemical and physical properties as well as its application as non- ionic fat-liquoring agents in leather industry. The obtained results showed that the number of ethylene oxide groups introduced in the fatty acids as well as their EO% increased as the temperature and time of the reaction increased. The highest ethoxylation number was obtained at 145°C for 8 hr. Also, the prepared ethoxylated products were found to be effective fat-liquors with high HLB values giving stable oil in water emulsions. The fat-liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement in the texture of the treated leather by the prepared fat-liquors as indicated from the scanning electron microscope (SEM) images was observed.

Optical and spectroscopic studies on tannery wastes as a possible source of organic semiconductors.

Tanning industry produces a large quantity of solid wastes which contain hide proteins in the form of protein shavings containing chromium salts. The chromium wastes are the main concern from an environmental stand point of view, because chrome wastes posses a significant disposal problem. The present work is devoted to investigate the possibility of utilizing these wastes as a source of organic semi-conductors as an alternative method instead of the conventional ones. The chemical characterization of these wastes was determined. In addition, the Horizontal Attenuated Total Reflection (HATR) FT-IR spectroscopic analysis and optical parameters were also carried out for chromated samples. The study showed that the chromated samples had suitable absorbance and transmittance in the wavelength range (500-850 nm). Presence of chromium salt in the collagen samples increases the absorbance which improves the optical properties of the studied samples and leads to decrease the optical energy gap. The obtained optical energy gap gives an impression that the environmentally hazardous chrome shavings wastes can be utilized as a possible source of natural organic semiconductors with direct and indirect energy gap. This work opens the door to use some hazardous wastes in the manufacture of electronic devices such as IR-detectors, solar cells and also as solar cell windows.