Poly(1-octene) was synthesized by polymerization of 1-octene using high performance MgCl 2 -supported TiCl 4 in combination with triethyl aluminum (TEAl) as cocatalyst in n-hexane for 2 h. Two catalysts, C 1 (diester catalyst) having di-isobutyl phthalate as internal donor and C 2 (monoester catalyst) having ethyl benzoate as internal donor were utilized for the atmospheric polymerizations to evaluate the influence of structurally different internal donors on the productivity, rate of polymerization and molecular weight profiles. The kinetic profile assessed in terms of variation of reaction parameters like temperature, cocatalyst to catalyst molar ratio and monomer concentration was found to be dependent on them. From these kinetic analyses, optimize conditions for polymerizations of 1-octene using diester as well as monoester catalyst were elucidated. The difference in the performance of diester and monoester catalyst system can be explained in terms of stability of active titanium species and chain transfer process. NMR spectroscopy of synthesized poly(1-octene) indicate predominantly isotactic nature.

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High performance MgCl 2 supported titanium catalyst having diisobutyl phthalate (DIBP) as internal donor has been synthesized. The organic components present in the catalyst have been studied through FTIR, 1D and 2D NMR spectroscopy. The results indicate presence of diethyl phthalate also in addition to DIBP. WAXD analysis has been done to study the features of MgCl 2 crystallites. Impact of donor components on the catalyst preparation leading to reaction pathways and performance for propylene polymerization has been evaluated.

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The transition metal catalysts have evolved dynamically in last few years for propylene polymerization and copolymerization in homogeneous media. The trends in catalyst development have moved from modification of Group...

Compounds with acidic and basic functional groups (aspartic acid, arginine, and cystine) are evaluated for inhibition of aldol condensation and dissolution of product in alkaline media. Inhibition efficiency of amino acids were studied at varied mole ratios of acetaldehyde to antipolymerant (2, 5, and 10), reaction temperature, and caustic concentration as a function of time (0.25, 1.0, 2.0 and 24.0 h) using UV spectrophotometry. Results obtained have been compared with efficiency of known amine derivatives. Arginine showed better efficiency when compared with aspartic acid and cysteine. Furthermore, data indicate that presence of carboxylic group in addition to amine group facilitates inhibition as well as dissolution of aldol polymer in alkaline media, while compounds with amine group acts as inhibitor for aldol condensation only.

X-ray photoelectron spectroscopy (XPS) has been applied to the study pertaining to preparation and characterization of catalysts used in propylene polymerization. The analysis has indicated support/donor interaction in active support (adduct) and active support/TiCl 4 interaction during catalyst preparation process. A systematic study has been made to identify suitable adduct from a set of three adducts for catalyst synthesis. Precise binding energy of Titanium species on catalyst surface has been measured and its dispersion on support has been evaluated to correlate catalyst performance with the surface spectroscopic parameters.