Gholam-Reza Nejabat
Department of Polymer Engineering, Shiraz Branch, Islamic Azad University, Shiraz, P.O. Box: 71993-3, Iran
[ 1 ] - A theoretical reasoning on why coordination catalysts supported on mesoporous supports produce HDPE crystalline nanofibers but not iPP crystalline nanofibers
Since 1999, when Takuzo Aida proposed the preparation of high density polyethylene (HDPE) crystalline nanofibers through polymerization of ethylene by a Cp2 TiCl2 /MCM-41 catalyst, many researchers have published various papers on different aspects of the idea. The published researches show that the endeavors to polymerize other types of alpha olefins, especially propylene, to obtain polyolefin...
[ 2 ] - Study of Ziegler-Natta/(2-PhInd)2ZrCl2 hybrid catalysts performance in slurry propylene polymerization
Several types of hybrid catalysts are made through mixing of 4th generation Ziegler-Natta (ZN) and (2-PhInd)2ZrCl2 metallocene catalysts using triethylaluminum (TEA) as coupling agent. Response surface methodology (RSM) is used to evaluate the interactive effects of different parameters including amounts of metallocene and TEA and temperature on metallocene loading. Analyzing the amounts of Al...
[ 3 ] - Changes in crystallinity of HDPE films containing different amounts of an oxo-biodegradable additive due to UVC exposure
Crystallinities of high-density polyethylene (HDPE) films containing various amounts of an oxo-biodegradable additive (HES-W) were investigated immediately after preparation and 6 weeks after ultraviolet (UV) irradiation (λ=254 nm). HDPE granules were mixed with oxo-biodegradable masterbatch in a twin-screw extruder and the extrudates were converted into films with thicknesses of 35±5 micromete...
[ 4 ] - Thermal and tensile behavior of LLDPE films containing limited amounts of an oxo-biodegradable additive and/or amorphous poly(1-hexene) before and after UV irradiation
Varying amounts of an amorphous poly(1-hexene) (PH, Mv 1.7×106 Da) were added to an LLDPE matrix containing 3% w/w Addiflex oxo-biodegradable additive (HES-W) and extruded and converted into films. Then the effect of presence of PH was investigated on microstructure, thermal and tensile behavior of polymer films before and after 6 weeks of ultra violet irradiation (UVR). Due to UVR, ...