Comparison of the Effects of Ethers Compounds as the New Internal Donors on Ziegler-Natta Catalysts for Polymerization of Propylene

In this study, 1,3-dimethoxy-2,2-bis(methoxymethyl)propane (Yield: 85%), 5,5-bis(methoxymethyl)-1,3-dioxane (Yield: 89%), 1-methoxy-2,2-bis(methoxymethyl)butane (Yield: 98%), 1,3-dimethoxy-2-((3-methoxy-2,2- bis(methoxymethyl)propoxy)methyl)-2-(methoxymethyl)propane (Yield: 78%) and 1-(2,2-bis(methoxymethyl)butoxy)-2,2-bis(methoxymethyl)butane (Yield: 93%) as the new internal electron donors were synthesized using the Williamson reaction. The synthesized ethers were characterized by FTIR, NMR, and GC techniques. The MgCl2-supported Ziegler-Natta catalysts were prepared with optimum ID/Mg molar ratio of synthesized internal electron donors, and also without the internal electron donor. Then, polymerization of propylene was carried out with the prepared catalysts and also with industrial Ziegler-Natta catalyst, with and without the external donor, in the presence of triethylaluminum as a co-catalyst and hydrogen as a chain transfer agent. Effects of ethers compounds as the new internal donors on the catalytic activity, Hydrogen response of the prepared catalysts, xylene solubility, weight-average molecular weight, molecular weight distribution, crystallinity degree, and thermal properties of the produced polypropylenes were examined. Then the performance of the prepared MgCl2-supported Ziegler-Natta catalysts with new internal electron donors on the properties of produced polypropylenes were compared with each other and also, with industrial Ziegler-Natta catalyst containing diisobutyl phthalate internal donor and catalyst without the internal electron donor.