Macromolecular Reaction Engineering

Cover: Copolymerizations of vinylidene fluoride with other fluoroolefins lead to polymers with unique properties. These high performance materials are mostly insoluble in common solvents. To avoid the use of fluorinated solvents or fluorinated auxiliaries during synthesis supercritical carbon dioxide can be used as reaction medium. Details on homogeneous phase copolymerizations up to complete vinylidene fluoride conversion and on copolymer properties are given in the article by E. Möller and S. Beuermann on page 8.

This issue of Macromolecular Reaction Engineering contains articles of the Special Series “New Production and Enabling Technologies in Polymer Reaction Engineering.”

Copolymerizations of vinylidene fluoride and hexafluoropropene in supercritical carbon dioxide are reported. Reactions in homogeneous phase to complete vinylidene fluoride conversion were carried out in the absence of any surfactant or fluorinated auxiliary. The homogeneity and required pressures are strongly dependent on the hexafluoropropene content of the copolymers.

Polyamides have had a long history. Resting on both the strength and polarity of the amide bond, they have continually added more properties and applications: by incorporating additional monomer types, by intelligent combinations of low-cost monomers, and by co-reaction and blending with other polymers. We attempt a broad review across the polyamides in all their variety.

Two mathematical models to simulate reactor backmixing effects on the outcome of an RAFT polymerization are presented. The results demonstrate that the level of back-mixing impacts the control of chain length and polydispersity of the living process and suggest that the impact of back-mixing should be reduced by an appropriate reactor design.

The use of microreactor technology in emulsion polymerization is being reported. The stability of the operation depends mainly on the uniformity of the feed. RTD studies confirmed plug flow, and a better mixing was confirmed by similar kinetics obtained when compared with batch process.