a practical criterion for synthesizing ethylen-1-butene copolymer in powder form in slurry polymerization with a ziegler-natta catalyst and predicting its incorporated 1-butene

The concentration of ethylene and 1-butene in n-hexane as polymerization media was calculated at five different pressure levels (4, 6, 8, 10, and 12 bar) and four different 1-butene concentrations (0.13, 0.26, 0.39, and 0.52 mol/l) in n-hexane at t= 80°c using the peng-robinson thermodynamic equation of state. some combinations of conditions were selected to perform the copolymerization reaction in the presence of an industrial ticl4 /mgcl2 ziegler-natta catalyst. the forms of the synthesized products were visually and qualitatively classified as either powder or sticky. the percentage of incorporated 1-butene comonomer into the polyethylene chains was analyzed using calibrated ftir tests. it was shown that for ethylene/1-butene concentration ratios (β) in n-hexane above approximately 1.80, the product forms as a powder. for values below 1.30 threshold, the product was sticky. thus, this ratio could be used as a criterion for selecting the proper combination of copolymerization pressure and 1-butene concentration when aiming to achieve a powdered form of the product. it was shown that β has a strong correlation with the weight percentage of 1-butene in the final lldpe polymer. therefore it can be used as an accurate prediction for wt.% of incorporated 1-butene into the lldpe chain within the studied concentration ranges with the specific catalyst system utilized.