Styrene microflow systems

Nagaki et al. (2008) also demonstrated the use of sec-BuLi 84 in a microflow system for the anionic polymerization of styrene 88, as a means of attaining a high degree of control over the molecular weight distribution of the resulting polymer. Employing a solution of styrene 88 (2.0 M) in THF and sec-BuLi 84 (0.2 M) in hexane and a tubular reactor... 

However, the use of a microflow system composed of a multilamination micromixer and a microtube reactor gives rise to a significant increase in the yield of the cycloadduct (79%) at the expense of the amount of the polymer (ca. 20 % based on styrene). The fast and efficient 1 1 mixing by a micromixer seems to be responsible. The extremely fast mixing might cause the cationic product to be formed at a very low concentration of styrene, which leads to the effective formation of the neutral cycloadduct. Similar mixing effects have also been observed for p-chloro- and p-methylstyrenes. 

Nagaki A, Tomida Y, Yoshida J (2008) Microflow-system-controlled anionic polymerization of styrenes. Macromolecules 41(17) 6322-6330... 

The [4 + 2] cydoaddition reaction ofN-acyliminium ion pools [35-37] with styrene derivatives followed by the elimination of a methyl group has been successfully carried out in a microflow system containing a multi-lamination micromixer [38, 39] (Scheme 5.17). 

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