SUMMARY:The polymerization of methyl methacrylate can be easily initiated in systems containing poly-2-vinylpyridine (polymer electron donor), liquid sulfur dioxide (acceptor), and carbon tetrachloride. The various types of polymer electron donors and acceptors which range widely in their electron affinity were also examined. The addition of DPPH causes the retardation; a decrease in the poly-2-vinylpyridine concentration or an increase in the monomer concentration leads to a higher molecular weight of poly-MMA. The values of kp/vG obtained under the various polymerization conditions are satisfactorily consistent with the literature values, suggesting that the polymerization proceeds through free radical intermediates. ZUSAMMENFASSUNG:Die Polymerisation von Methacrylsauremethylester kann in Systemen, die Poly-2-vinylpyridin (als polymerer Elektronendonator), flussiges Schwefeldioxid (als Acceptor) und Tetrachlorkohlenstoff enthalten, leicht initiiert werden. Verschiedene Arten van polymeren Elektronendonatoren und -acceptoren mit einem grol3en Bereich .der Elektronenaffinitat wurden ebenfalls untersucht. Der Zusatz von DPPH bewirkt eine Verzogerung der Polymerisation; eine Verminderung der Poly-2-vinylpyridin-Konzentration oder eine Erhohung der Monomerenkonzentration ergibt ein hoheres Molekulargewichtes. Die unter den verschiedenen Polymerisationsbedingungen erhaltenen Werte von kp/l/k7 stimmen mit den in der Literatur angegebenen Werten befriedigend iiberein und weisen darauf hin, dal3 die Polymerisation iiber freie Radikale verlauft.

A kinetic study has been made of the polymerization of methyl methacrylate (MMA) initiated by a charge‐transfer complex of poly‐2‐vinylpyridine (electron donor) and liquid sulfur dioxide (acceptor) in the presence of carbon tetrachloride. It is concluded that the polymerization proceeds through free‐radical intermediates, as with the pyridine‐liquid sulfur dioxide complex system. The association constants K of acceptor and polymer electron donors which range widely in their molecular weight were determined spectrophotometrically, and it has been found that both K and overall rate of polymerization Rp of MMA decrease with increasing molecular weight of polymer donor; contrary to this, molecular weight of PMMA formed increases with increasing molecular weight of the polymer donor. Other kinetic behaviors was essentially the same as in the pyridine–liquid sulfur dioxide system, i.e., Rp is proportional to the square root of the concentration of the complex and to the 3/2‐order of the monomer concentration; Rp is clearly sensitive to the carbon tetrachloride concentration at low concentration of carbon tetrachloride, but for a higher concentration it is practically independent of the carbon tetrachloride concentration. It has been deduced from a kinetic mechanism for the initiation that a primary radical may be produced from the reduction of carbon tetrachloride by an associated complex consisting of liquid sulfur dioxide–polymer donor and the monomer.

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The polymerization of methyl methacrylate can be easily initiated in systems containing poly‐2‐vinylpyridine (polymer electron donor), liquid sulfur dioxide (acceptor), and carbon tetrachloride. The various types of polymer electron donors and acceptors which range widely in their electron affinity were also examined. The addition of DPPH causes the retardation; a decrease in the poly‐2‐vinylpyridine concentration or an increase in the monomer concentration leads to a higher molecular weight of poly‐MMA. The values of kp/√kt obtained under the various polymerization conditions are satisfactorily consistent with the literature values, suggesting that the polymerization proceeds through free radical intermediates.