Living Anionic Polymerizations of 4-(1-Adamantyl)styrene and 3-(4-Vinylphenyl)-1,1‘-biadamantane

Anionic polymerizations of new styrene derivatives, 4-(1-adamantyl)styrene ( 1 ) and 3-(4-vinylphenyl)-1,1‘-biadamantane ( 2 ), were carried out with sec -butyllithium, cumylpotassium, and lithium- or potassium naphthalenide in THF at −78 °C for 3−4 h. The polymerizations of 1 and 2 quantitatively proceeded to afford the polymers possessing the predicted molecular weights based on the molar ratios between monomers and initiators and the narrow molecular weight distributions ( M w / M n = 1.03−1.13). The stability of propagating chain ends of poly( 1 ) and poly( 2 ) was confirmed by the quantitative initiation efficiency in the sequential copolymerization of 1 and 2 with styrene or isoprene. Novel well-defined block copolymers, poly( 1 )- b -polystyrene, poly( 1 )- b -polyisoprene, poly( 1 )- b -polyisoprene- b -poly( 1 ), poly( 2 )- b -polystyrene, and poly( 2 )- b -polyisoprene- b -poly( 2 ), were anionically synthesized. The resulting poly( 1 ) and poly( 2 ) started to decompose over 340 °C and showed remarkably high glass transition temperatures ( T g ) at 234 and 232 °C, respectively. The T g values of anionically synthesized random copolymers of 1 and styrene could be changed between 100 and 230 °C by the feed molar ratio of comonomers. The incorporation of bulky and stiff adamantyl or 1,1‘-biadamantyl moiety unequivocally induced the high thermal stability of novel 4-substituted polystyrenes, poly( 1 ) and poly( 2 ).