A continuous fl ow microwave system based on a transmission line short-circuited waveguide reactor concept is described. The continuous fl ow reactor is capable of operating in a genuine high-temperature/high-pressure process window (310 ° C/60 bar), applying a microwave transparent and chemical resistant cylindrical γ -Al 2 O 3 tube as reaction zone. The system can be operated in an extremely energy effi cient manner, utilizing 0.6 -6 kW microwave power (2.45 GHz). The application of the reactor for processing four chemical transformations in a high-temperature/high-pressure regime with a throughout of 3.5 -6.0 l/h is demonstrated.
The anionic copolymerization of 5‐(N,N‐dialkylamino)isoprenes and 1,3 ‐butadiene was investigated in hexane. We found that basicity and increasing amount of the polar monomer has a strong influence on the microstructure of polybutadiene. All tested 5‐(N,N‐dialkylamino)isoprenes were incorporated much faster into the copolymer than butadiene. Depending on the alkyl substituents the resulting copolymer is either a nearly perfect diblock or shows a considerable tapered structure.
SUMMARY The anionic polymerization of 5-(N,N-dialkylamino)isoprenes with set-butyllithium was investigated in different solvents under various conditions. The homopolymerization can be described as a 2"d order reaction with respect to the monomer concentration, indicating that two monomer units are involved in the rate determining reaction. A mechanistic proposal to explain this unusual behaviour is based on the structure of amino-functional lithium organic compounds.
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