Abstract
To investigate the specific strategy for sequence regulation with living anionic polymerization, three sequence defined polymers with similar number of SiH functional groups per chain but totally different periodicities which distributed as gradient, tandem, and symmetrical structures were synthesized. Through different feeding methods and coupling reaction after polymerization during the living anionic copolymerization of styrene (St) and dimethyl-[4-(1-phenylvinyl)phenyl]silane (DPE-SiH), the synchronous regulation of monomer sequence and functionalized block periodicity in polymer chains was successfully achieved. The monomer sequence distributions in these three structures were confirmed by in situ H-1 NMR. As the monomer sequence and block periodicity are synchronously regulated, this effort could promote the further development of the sequence regulation and the design of novel functionalized polymers with living anionic polymerization method, and the strategy we investigated also can improve the novel polymer designs. Then, these gradient, tandem, and symmetrical polymers were applied as backbones for the synthesis of corresponding bottlebrush polymers. The polymeric branches (the chain-end alkynyl-functionalized polystyrenes, PS-yne) were conveniently and efficiently grafted onto the backbones via hydrosilylation, with all conversions above 97%. The basic solution and thermal properties of the bottlebrush polymers and their corresponding backbones were investigated, and the results indicated that the different sequence structures and block periodicities of the polymers display remarkable influences.