Die Geschwindigkeit der Bildung der Triaryl‐benzylphosphoniumchloride (III) aus den Triarylphosphinen (I) und Benzylchlorid (II) in Benzol/Methanol wird durch ortho‐ständige Methoxyreste in den Phenylkernen (If), (Ih) und (Ik) deutlich erhöht, während ortho‐ständige Methylgruppen (Ib) und (Id) eine merkliche Verringerung der Reaktionsgeschwindigkeit verursachen.
Six commercially produced largely amorphous polyether elastomers are described. These are polyepichlorohydrin, poly(epichlo‐ rohydrin‐
co
‐ethylene oxide), poly(epichlorohydrin‐
co
‐allyl glycidyl ether), poly‐ (epichlorohydrin‐
co
‐ethylene oxide‐
co
‐allyl glycidyl ether), poly(propylene oxide‐
co
‐epichlorohydrin‐
co
‐allyl glycidyl ether), and poly(propylene oxide‐
co
‐allyl glycidyl ether). Structure and properties including molecular weight and solution behavior for the raw polymers are discussed. Laboratory and commercial prepayration of the polymers are described. Large‐scale polymerization employs a continuous process with the reactants either in solution or as a slurry. Mixing and milling procedures are described in the commercial processing and fabrication section. Compounding information including the use of curing systems, stabilizers, antioxidants, fillers, and plasticizers is presented as well as physical properties and uses of vulcanizates of these polymers. Health and safety considerations pertaining to handling of the constituent monomers, curing systems, and raw polymers are discussed. Economic aspects are described.
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