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Electroinitiation of Anionic Polymerizations

المؤلف:  A. Ravve

المصدر:  Principles of Polymer Chemistry

الجزء والصفحة:  P190-191

2026-01-18

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Electroinitiation of Anionic Polymerizations

Electrolytic polymerizations were described in the section dealing with cationic polymerizations. Anionic polymerizations can also be initiated in an electric field. When LiAlH₄ or NaAl(C₂H₅)₄ are used as electrolytes in tetrahydrofuran solvent "living" polymers can be formed from a-methylstyrene [190]. The deep red color of carbanions develops first at the cathode compartments of divided cells. By cooling the solutions to -80°C almost quantitative conversions to high molecular weight polymers take place [190]. Similar conditions yield polystyrene [191]. 4-vinyl pyridine polymerizes in liquid ammonia in the same manner [191]. Initiation results from reduction of the monomer by direct electron transfer at the cathode to form a red-orange vinyl pyridyl radical-anion:

Another example is polymerization of isoprene in an electric field in tetrahydrofuran solution. Here too, a "living" polymer forms.