Conductive plastics are new generation functional materials with potential application in electronics, space and aviation industries. Polypropylene (PP) and polyethylene (PE) being most common, widely available and cheapest thermoplastic, if made conductive, can be revolutionary in the field of engineering thermoplastics. The article deals with the fabrication of electrically conductive PP and PE for electromagnetic interference/ radio frequency (EMI/RF) shielding applications and protection against electrostatic discharge (ESD). It reviews different fillers used by researchers to fabricate conductive PP and PE, several factors that affect the electrical conductivity of thermoplastic composites and various processing methods that can be adopted to prepare such composites. It exhaustively covers the preparation of such conductive composites, the processing methods involved therein, and the electrical properties of the end material. Emphasis has been given to comprehend the percolation threshold and means to reduce the latter in order to achieve high electrical conductivity in PP-and PE-based composites at relatively low filler loading. POLYM. COMPOS., 35:900-914,

This paper suggests a new ultrasonic-based enhanced oil recovery (EOR) model for application in oil field reservoirs. The model is modular and consists of an acoustic module and a heat transfer module, where the heat distribution is updated when the temperature rise exceeds 1 °C. The model also considers the main EOR parameters which includes both the geophysical (i.e., porosity, permeability, temperature rise, and fluid viscosity) and acoustical (e.g., acoustic penetration and pressure distribution in various fluids and mediums) properties of the wells. Extended experiments were performed using powerful ultrasonic waves which were applied for different kind of oils & oil saturated core samples. The corresponding results showed a good matching with those obtained from simulations, validating the suggested model to some extent. Hence, a good recovery rate of around 88.2% of original oil in place (OOIP) was obtained after 30 min of continuous generation of ultrasonic waves. This leads to consider the ultrasonic-based EOR as another tangible solution for EOR. This claim is supported further by considering several injection wells where the simulation results indicate that with four (4) injection wells; the recovery rate may increase up-to 96.7% of OOIP. This leads to claim the high potential of ultrasonic-based EOR as compared to the conventional methods. Following this study, the paper also proposes a large scale ultrasonic-based EOR hardware system for installation in oil fields.

Polypropylene/clay nanocomposites were prepared by melt blending technique. A PP homopolymer was melt blended with commercial nanoclay masterbatch at different concentration (5, 10 and 15 wt% of nanoclay) using Laboratory Mixing Extruder (LME). The morphology of the nanocomposites was characterized using Scanning Electron Microscope (SEM). The viscoelastic and thermomechanical properties were analyzed via Dynamic Mechanical Analysis (DMA). The morphological analysis showed that the nanoclay was well distributed in the PP matrix. The DMA analysis showed an increase in storage modulus of nanocomposites which indicates an enhancement of stiffness and thermal stability of the prepared nanocomposite samples. In addition, a nanoindentation test was performed to determine the dynamic nanomechanical properties of two nanocomposites samples (NS-5 and NS-15). Load sweep test results showed that NS-15 has a slightly higher storage and loss modulus than that of NS-5. Both the samples also showed a decreasing modulus as a function of depth, indicating the presence of a stiffer surface layer in the samples. Frequency sweep tests were also performed on each sample, and display a moderate viscoelasticity with modulus values that increased slightly as a function of frequency. Loadcontrolled ramping force scratch test was also carried out and the results showed that NS-15 had a greater elastic recovery than sample NS-5 as well as a greater overall scratch resistance.

The discovery of rare earth based phosphors in 1960s started a new era of luminescence. In comparison with sulfide-based phosphors, strontium aluminates received worldwide acceptance because of their chemical stability and good luminescent properties. The SrAl x O y :Eu 2+ ,Dy 3+ phosphors excited by UV or visible light emit phosphorescence in the blue-green region after the excitation source has been removed, and the phosphorescence last for more than 15 h. The major disadvantage of SrAl x O y :Eu 2+ ,Dy 3+ phosphors is that they are prone to hydrolysis and their luminescent properties gradually deteriorate. The dispersion of these phosphors in a waterproof polymer matrix is an alternative method reported for retaining their luminescent properties. The review extensively deals with strontium aluminate based luminescent materials, the mechanism of luminescence, their synthesis techniques, and different mixing procedures to prepare polymer/strontium aluminate composites. Different methods to improve the dispersion of the strontium aluminate in the polymer matrix are also outlined. C