epoxy – polysulfide copolymers without or with low amounts of epoxy in their structure have poor mechanical properties in oxidative curing system.to strengthen the mechanical properties of polysulfide elastomer inclusion of epoxy resin (epon828) as hard segment was studied. ft-ir spectroscopy and rheometry were used to verify the formation of epoxy-polysulfide copolymer.  results obtained from ...

background and aims. the aim of this clinical investigation was to compare clinical and microbiological effectiveness of adjunctive chx gel in the treatment of periodontitis. materials and methods. twenty-four subjects with localized or generalized moderate-to-severe chronic periodontitis underwent scaling and root planing. one tooth in each quadrant with a probing depth of >4 mm was chosen for...

aloe vera is a plant of the liliaceae family with a brilliant history in disease treatment. in addition to the pharmaceutical, cosmetic, and health care industries, this plant is used in food industry due to having various nutrients such as amino acids and various vitamins or anti-bacterial compounds. the purpose of this study was to investigate the effects of variables such as temperature, tim...

A hydrogel was prepared by crosslinking aqueous solutions of sulfonated polyacrylamide/chromium triacetate for use in water shut off operations. Gel swelling and the effects of salinity, injection time and flow rate on residual resistance factor (Frr) were investigated. In the presence of electrolytes, gel swelling decreased by about 80%. Results showed that oil permeability increased as inject...

in this paper, carbon nanotubes (cnts) were added into chitosan (cs) hydrogels in the form of chitosan modified cnts (cs-cnts) composites to prepare carbon nanotubes hydrogels (cnts-gel). the products, named cs-mwcnts, were characterized by scanning electron microscope (sem) and fourier transform infrared (ftir) spectroscopy. swelling properties and effect of ph on controlled release performanc...

In this paper, polyacrylamide/chromium acetate gel polymer system was prepared as water shut-off system to control water production in one of the Iranian oil reservoirs condition. Effect of various parameters such as temperature (90 °C) and water formation from view point of salinity and divalent cations, was evaluated on the gelation kinetic and gel strength using bottle testing method. Th...

in this paper, polyacrylamide/chromium acetate gel polymer system was prepared as water shut-off system to control water production in one of the iranian oil reservoirs condition. effect of various parameters such as temperature (90 °c) and water formation from view point of salinity and divalent cations, was evaluated on the gelation kinetic and gel strength using bottle testing method. the re...