Novel Synthesis of a Macromonomer Having Organosilyl and Amino Groups

Reaction between dimethyldivinylsilane (1) and N,N′-diethyl-N-lithio-ethylenediamine (2a) in the presence of N,N′-diethylethylenediamine (3a) in THF at 20°C gave a monoadduct, 3,3-dimethyl-6-ethyl-3-sila-6,9-diaza-1-undecene (4a). An anionic self-polyaddition reaction of 4a in the presence of lithium diisopropylamide (LDA) proceeded to form oligomers. Each of the oligomers thus obtained was found to carry a polymerizable vinylsilane moiety at the oligomer chain terminal. As a result, a new type of macromonomer having alternating repeating units of ethylenediamine and organosilyl groups was synthesized. Acid-base titration showed the macromonomer to have unique characteristics on protonation of diamine moieties. Anionic polyaddition reactions between 1 and N-lithio-piperazine (2b) in the presence of piperazine (3b) also gave a macromonomer consisting of alternating repeating units of piperazine and organosilyl groups (4b). Radical copolymerizations of styrene with 5b gave comblike graft copolymers.