Lawrence Suchow, Norman R. Stemple
JES
Both 4- and 3-(tert-butyldimethylsilyl)oxystyrene (MSOST) undergo living anionic polymerization at room temperature with sec-butyllithium (sBuLi) in cyclohexane or methylcyclohexane upon injection of a small amount of tetrahydrofuran. Desilylation can be conveniently afforded with hydrogen chloride or tetra(alkyl)ammonium fluoride to provide poly(hydroxystyrene) (PHOST) with a narrow molecular weight distribution, which could be further transformed to other polystyrene derivatives. 13C NMR spectra of poly(tert-butyldimethylsilyloxystyrene) (PMSOST) and PHOST prepared under different conditions (tetrahydrofuran vs. cyclohexane, -78°C vs. 20°C) have indicated that the room temperature living polymerization in the hydrocarbon-rich solvent produces polymers with high syndiotacticity. Similarly, 4-(tert-butyldiphenylsilyl)oxystyrene (PhSOST), a new monomer, provides living anionic polymerization at room temperature. Desilylation of this polymer can be achieved using tetra(n-butyl)ammonium or tetraethylammonium fluoride. Inertness of the phenylsilyl ether to HCl allows selective desilylation of the dimethylsilyl ether with HCl in the presence of the phenylsilyl ether group, providing a new route to interesting macromolecules. Application of the selective desilylation technique to the synthesis of a block copolymer of HOST and 4-tert-butoxycarbonyloxystyrene (BOCST) is described.
Lawrence Suchow, Norman R. Stemple
JES
S.F. Fan, W.B. Yun, et al.
Proceedings of SPIE 1989
R. Ghez, J.S. Lew
Journal of Crystal Growth
Biancun Xie, Madhavan Swaminathan, et al.
EMC 2011