| Summary: | Density functional theory (DFT) was used to study the regioselectivity of the copolymerization of propylene and the <i>bis</i>-styrenic molecules (DVB and BVPE) using a zirconocene catalyst. This study reveals the following: when hydrogen is introduced to reactivate the catalyst on the vinyl bonds containing DVB or BVPE, the second vinyl bond is inserted into the polymer in a regio-irregular 1,2-way. (I) The 1,2-insertion mode forms more thermodynamically stable products. (II) The 2,1 insertion, DVB-PP<sub>1,</sub> or BVPE-PP<sub>1</sub> needs to rotate 180° along the Zr-C<sub>1</sub> bond to complete the process; thus, it is easier to accomplish the 1,2 insertion. (III) The analysis of the local electrophilicity/nucleophilicity index and the Fukui functions also indicate that the 1,2-insertion mode is the optimal insertion mode. Investigating the mechanism of this experimental phenomenon is important in the development of a functionalization strategy for polypropylene (PP) polymers.
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