POS1-0375
Design of Branched Polymers Based on Silyl Radicals in Radical Polymerization of Si-H Containing Monomers
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Yuki ISHIKAWA (Nagoya University)
Co-Author(s)
Abstract
Although carbon and silicon both belong to Group 14 of the periodic table, they exhibit distinct chemical properties. In terms of their bonds with hydrogen, Si–H bonds are typically weaker than C–H bonds and can therefore undergo hydrogen atom abstraction by alkyl radicals. Owing to this characteristic, silanes have been widely used as reducing agents in organic reactions that proceed via radical mechanisms. In contrast, their application in radical polymerization has remained limited. If silyl radicals generated through hydrogen atom abstraction from Si–H bonds can be incorporated into polymerization processes, new polymer architectures containing silicon atoms in the polymer chains could be developed. In this study, we developed radical polymerization of monomers bearing pendant Si–H bonds, in which silyl radicals were generated from the Si–H moieties. During the polymerization, hydrogen atom abstraction from the Si–H bonds occurs through chain-transfer processes, generating the silyl radical that is subsequently involved in the polymerization. This approach enabled the synthesis of branched polymers containing silicon atoms at the branching points. Through various investigations, we found that the frequency of hydrogen atom abstraction from the Si–H bonds was able to be controlled depending on the catalyst and polymerization conditions. Furthermore, based on the reactiyity of silyl radicals, which is distnct from that of carbon radicals, we designed unique branched polymers with specific structures at the branching points. The physical properties and degradability of the obtained polymers were also evaluated.
