a two-dimensional single particle finite element model was used to examine the effects of particle fragmental pattern on the average molecular weights, polymerization rate and particle overheating in heterogeneous ziegler-natta olefin polymerization. a two-site catalyst kinetic mechanism was employed together with a dynamic two-dimensional molecular species in diffusion-reaction equation. the i...

several types of hybrid catalysts are made through mixing of 4th generation ziegler-natta (zn) and (2-phind)2zrcl2metallocene catalysts using triethylaluminum (tea) as coupling agent. response surface methodology (rsm)is used to evaluate the interactive effects of different parameters including amounts of metallocene and tea andtemperature on metallocene loading. analyzing the amounts of al and...

The reliable and efficient counting of active sites in catalytic olefin polymerization has been realized by using acyl chloride as the quench-labeling agent. However, molar ratio to alkylaluminum cocatalyst must be larger than 1 order completely depress side reactions between quencher Al-polymeryl that is formed via chain transfer reaction. In this work, a tetrahydrofuran/thiophene-2-carbonyl (...

Ultrafine aluminum and boron powders have been identified as very promising fuels as part of energetic materials formulations. However, the large specific surface area that gives these powders a high reactivity also makes them particularly difficult to maintain in an unoxidized state. They also agglomerate easily during compounding processes. The coating of the particles by a polymer could offe...

Chemical recycling of plastic waste has promise as a complementary technology to increase eco-efficiency plastics life cycles. Accumulation impurities in feed streams can affect sensitive compounds such the Ziegler–Natta catalyst systems commonly used produce polyolefins high density polyethylene (HDPE) and linear low (LLDPE). In poison study, influence impurities—more specifically NO N2O—on sy...

Ab initio SCF-LCAO-MO all-electron calculations have been performed for the catalyzed reaction, related to the Ziegler-Natta polymerization process TiCl.·Al(CH3)3+C2H. -+TiCl •. Al(CH3h·C3H7. The energy of the Ti-Al--ethylene complex during the reaction pathway is associated to the following processes: First, the ethylene coordinates to the catalyst complex and subsequently it reacts with the m...

Several types of hybrid catalysts are made through mixing of 4th generation Ziegler-Natta (ZN) and (2-PhInd)2ZrCl2  metallocene catalysts using triethylaluminum (TEA) as coupling agent. Response surface methodology (RSM) is used to evaluate the interactive effects of different parameters including amounts of metallocene and TEA and temperature on metallocene loading. Analyzing the amounts of Al...

Modeling and Simulation of an Emulsion Copolymerization Process Sabrina Copelli*, Mario Dente, Marco Derudi, Giulia Bozzano, Vincenzo Torretta Università degli Studi dell’Insubria Dip. di Scienza e Alta Tecnologia Via G.B. Vico 46 21100 Varese Italy b Politecnico di Milano Dip. di Chimica, Materiali e Ingegneria Chimica “G. Natta”P.za Leonardo da Vinci 20133 Milano Italy sabrina.copelli@uninsub...