Hello Dear MS users,
I have a question about homopolymer building...when i created isotactic  polypropylene chains using MS Build-> Homopolymer->library->Olefins->propylene, everything is OK. But when I sketched propylene with myself and Built it as repeat unit, and created polypropylene chain by applying
1-library->current project  
2-Repeat unit->my sketched  propylene repeat unit
3-Tacticity->isotactic
But the final structure is not isotactic polypropylene and have different tactility!!! Would you please tell me why these two results are different?
I think this problem can be very important when a user wants to create an isotactic polymer, that its repeating units is not in the MS library.

Best Regards
Sousa