Czs-l,4-polyisoprene

In contrast to the behavior of butadiene stand the reactions of the substituted butadienes. As many workers have shown, iso-prene is converted to an essentially all czs-l,4-polyisoprene at RsAl/TiCb = 1.0. Likewise, 2,3-dimethyl-l,3-butadiene (Yen, 1959a), and 2-iert-butyl-l,3-butadiene (Marconi et al., 1964) are polymerized to predominantly m-1,4 polymers under the same conditions. At other ratios (Al/Ti > 1.0) isoprene is still converted to a predominantly cis-1,4 polymer, though in de-... 

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