Copolymerization of ethylene with propylene is carried out semi-continuously in toluene at atmospheric pressure and with various propylene/ethylene molar ratios. The polymerization temperature and cocatalyst/catalyst molar ratio were also varied in a wide range. Cp2ZrCl2/MAO System was used as catalyst. The viscosity average molecular weights of copolymers obtained were determined by measuring the intrinsic viscosity [ h] and application of the Mark-Houwink equation. The values of molecular weights were found to be dependent on operating conditions except on polymerization time in the range 5-30 min. increasing the polymerization temperature, propylene/ethylene and cocatalyst/catalyst molar ratios caused a continuous decrease in molecular weight. An important reason for this effect was shown to be accelerated chain transfer reactions.

Glucomannan carboxymethylation is conducted to increase its hydrophobic properties and expand its interaction with hydrophobic compounds. However, glucomannan has high molecular weight and long polysaccharide chain which prevented the modification of its amphiphilic properties. This study aimed to examine the effect of molecular weight, deacetylation, and carboxymethylation on glucomannan properties. Performance of the modified glucomannan to stabilize oil in water (o/w) emulsion was also studied. Ultrasonication was applied to glucomannan at 40 kHz for 15-45 min to obtain various molecular weights. Sodium carbonate (Na2CO3) and sodium monochloroacetate were used as deacetylation and carboxymethylation agents, respectively. The results show that decrease molecular weight supported the deacetylation and the carboxymethylation process on attaching the hydrophobic groups to the glucomannan chain, hence, lowering the hydrophilic properties and swelling degree of glucomannan. Structural and morphological changes of glucomannan after modifications were confirmed from the IR spectra and SEM images. Excellent performance of the amphiphilic glucomannan on stabilizing o/w emulsion was observed as only ~5% phase separation occurred after 300 h of storage in ambient conditions. Hence, ultrasonication is proposed as a suitable preliminary treatment for amphiphilic glucomannan production.

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 reactor. PS is separated into fractions with different average molecular weights, and the structure of the fractions is characterized. It has been found out that the interfacial chemistry property of PS is closely related to the molecular structure. The adsorption reaches the maximum value near the critical micellar concentration. Furthermore, there are significantly different interfacial activity and adsorptive property for each fraction. As the lab test result shows, the oil-displacement efficiency for each fraction is changed. The interfacial tension between crude oil and water is declined, and the oil-displacement efficiency of the system is greatly increased as PS or its fraction is used with electrolytes.