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Haloacetaldehyde polymers and macromolecular asymmetry
Authors:Otto Vogl
Abstract:Polyhaloaldehydes play a special role in aldehyde polymerization. The most prominent trihaloacetaldehyde polymer, polytrichloroacetaldehyde, opened the door to new concepts in polymer chemistry: first, cryotachensic polymerization, the separation of the initiation step from the propagation steps with the ceiling temperature principle for the fabrication of insoluble and infusible polymers, and second, the concept of macromolecular asymmetry and stereospecific and conformationally specific polymerization. Trichloroacetaldhyde could be readily polymerized with a wide range of anionic (and also some cationic) initiators. When the anionic polymerization was initiated with chiral anions, it gave polychloral of one helix sense. To understand the genesis of the polymerization, the oligomerization was investigated to learn how the stereochemistry of the polymerization was established, also in chiral form. All 10 fluoro‐, chloro‐, and bromo‐substituted trihaloacetaldehydes were synthesized as necessary and polymerized, and the polymers were investigated. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2623–2634, 2000
Keywords:haloaldehyde polymers  polychloral  macromolecular asymmetry  polybromal  bulk size  side groups  oligomers  optical activity
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