Microflow systems block copolymerization

The polymerization can be restarted when the same or a different monomer is added. The use of a different monomer leads to block copolymerization. Within the short residence time in a microflow system at low temperature, the polymer chain was really living. In fact, block copolymerization by adding the second monomer in the microflow system has already been achieved by using a strong proton acid, such as trifluoromethanesulfonic acid (TfOH), as an initiator in a microflow system (see Section 9.4.8). 

Figure 9.6 Microflow system for cationic block copolymerization...

Block copolymerization of IBVE and n-butyl vinyl ether (NBVE) can also be successfully achieved using a microflow system consisting of two micromixers... 

An example of microflow systems for block copolymerization is shown in Figure 14.11. The first monomer IBVE is mixed with TfOH in the first micromixer (Ml). Introduction of the second monomer (NBVE or EVE) at the second micromixer M2 results in the formation of a polymer of higher molecular weight with a narrow molecular weight distribution. Block copolymerization can be carried out with any combination and with either order of monomer addition, as shown in Table 14.4, demonstrating that the present method serves as an effective technique for the synthesis of block copolymers. The observations illustrate the possibility of using MCPT in the synthesis of structurally well-defined polymers and copolymers both in the laboratory and industry. 

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