Ethylene and 1-butene copolymerization catalyzed by a Ziegler–Natta/Metallocene hybrid catalyst through a 23 factorial experimental design

In this work, a 23 factorial experimental design for the evaluation of ethylene–1-butene copolymerization was employed. The following reaction parameters were used as independent variables: catalyst type, Al/Ti molar ratio and 1-butene concentration. The copolymerization was carried out using hybrid Ziegler–Natta/Metallocene catalysts with different titanium molar ratios. The catalyst activity and polymer characteristics were statistically analyzed through response surface methods. It was found that the catalyst type has a significant effect on activity, melt flow index and 1-butene content. Copolymers presented crystallinity values ranging from 46 to 58% and melt temperature in the 128–131 °C range. Copolymer comonomer content varied from 2 to 6% in weight.