Preparation and Separation of Styrene Oligomers

Styrene oligomers having propyl end groups were prepared by initiating oligomerization with ethyllithium and terminating with 1-bromopropane in ethyl ether  

Nonpolar eluents (2,2,4-trimethylpentane and isopropyl ether) and polar eluents (methanol and acetonitrile) eluted the oligomers more slowly than chloroform by a factor of two. It is clear that these eluents cause separation to be controlled by an adsorption mechanism with a negligible size exclusion effect. Using these eluents, we observed peak separation or broadening due to the diastereomers for the dimer and higher oligomers. 

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