microstructural investigation of low molecular weight 1,4-polybutadiene (1,4-pbd) was studied by 1h and 13c nuclear magnetic resonance spectroscopy (nmr). the isomer contents of 1,4-cis, 1,4-trans and 1,2- vinyl in polybutadiene microstructure were determined. the number average molecular weight for low molecular weight polybutadiene was measured by nmr techniques and comparison was made with g...

Alkaline/surfactant/polymer (ASP) flooding has been extensively applied to enhancing oil recovery. As an oil displacement agent, pe1troleum sulfonate (PS) is widely used in ASP pilot experiments. It is very important to find a petroleum sulfonate with a high interfacial activity and low adsorption loss. Anionic surfactant petroleum sulfonate is synthesized in a single-tube film sulfonation reac...

atom transfer radical polymerization (atrp) of styrene was carried out at 105°c and a monte carlo simulation was employed to model the system. the variations of monomer conversion, the initiator concentration, average molecular weight, and molecular weight distribution were evaluated as the reaction proceeded. according to the results obtained, for similar reaction time, monomer conversion is h...

polyacrylontrile synthesis, via atom transfer radical polymerization, is studied in various initiator concentrations, transitional metal catalyst and different concentrations of cubr2. the variations of monomer conversion and the lin-earity of semi-logarithmic kinetic profile which is the evidence of living polymerization and constant radical concentration in the reaction medium, were revealed ...

bis(indenyl)zirconium dichloride as a catalyst was synthesized using a modified method at the room temperature. polymerization of ethylene and copolymerization of ethylene and propylene were carried out by this metallocene catalyst. ethylene propylene (p/e) feed ratios of 0.25, 0.5, 1, and 2 were employed into the copolymerization systems. copolymerization conditions like cocatalyst/catalyst ra...