in the current work, ethylene polymerization was investigated from a mathematical modeling point of view. the initiation (activation), propagation, termination, and deactivation reactions were taken into account and the relevant equations used in the modeling were obtained from the elementary reactions. some assumptions including neglecting the transfer and deactivation reactions were considere...

After five decades of largely serendipitous (albeit formidable) progress, catalyst design in Ziegler-Natta olefin polymerization, i.e., the rational implementation of new active species to target predetermined polyolefin architectures, has ultimately become a realistic ambition, thanks to a much deeper fundamental understanding and major advances in the tools of computational chemistry. In this...

A method for the determination of Ti and V using inductively coupled plasma atomic emission spectrometry (ICP OES) in Ziegler-Natta polymerization catalysts is proposed. The concentrations of both Ti and V are efficiently determined after catalyst acid digestion with a mixture of HNO3 + HCl + HF and heating (160 degrees C for 6 h) or with 10% (v/v) H2SO4 and heating (160 degrees C for 6 h) or w...

Syndiotactic 1,2-polybutadiene (sPBD) is an important industrial polymer with a wide variety of uses; however, there is only a very limited number of catalysts currently capable of producing this polymer with a high degree of syndiotacticity. Only one such catalyst has been structurally characterized, when in 1967 Natta et al. published a low-resolution crystal structure of the cobalt complex [...

this is a report on the study of high melt flow, highly isotactic polypropylene homopolymer synthesized in liquid monomer using a fifth generation ziegler-natta catalytic system. at highest catalyst productivity, the response of thecatalyst to hydrogen as chain transfer is studied. melt flow rate is controlled by hydrogen as chain transfer from 0.4 to 300 g/10min with changing the amount of hyd...