21 methyl-substituted cyclosiloxanes

U. Pemisz, N. Auner, M. Backer, Photoluminescence of phenyl- and methyl-substituted cyclosiloxanes, in Silicones and Silicone-Modified Materials (Eds. S. J. Clarson, J. J. Fitzgerald, M. J. Owen, S. D. Smith) ACS Symposium Series 729, Am. Chem. Soc., Washington DC, 2000, Chap. 7, p. 115. 

Equilibrium copolymerization of unstrained cyclosiloxanes leads to random copolymers.Thus, for example, equilibrium copolymerization of diethylcydotetrasiloxane with cydotetrasiloxanes having various R R SiO units (R = R = methyl or phenyl, or R = methyl, and R = phenyl) gave copolymer of units randomly distributed along the chain. ° The regioselectivity of the ROP of unsymmetrically substituted cydotetrasiloxanes such as 2,2,4,4,6,6-hexamethyl-... 

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