Photoreduction of benzophenone by trithianes as the initiation step in radical polymerization

• Autorzy: Andrzejewska E. , Hug G. , Andrzejewski M. , Marciniak B.
• Konferencja: Reactive Intermediates in Sulfur Chemistry Workshop dedicated to Professor Klaus-Dieter Asmus on His 60th birthday August 23-26, 1998, Poznan, Poland
• Języki publikacji: EN

Abstrakty

EN

This work was presented at the Workshop on Reactive Intermediates in Sulfur Chemistry (Poznań, 1998). It is a summary of earlier investigations on the role of cyclic sulfides (1,3,5-trithiane derivatives) in accelerating the initiation of polymerization induced by benzophenone (BP). The primary photochemical reactions between BP and trithianes were followed by nanosecond laser flash photolysis. Tripletquenching rate constants and quantum yields for electrontransfer products and ketyl-radical formation were measured. Photoinduced polymerizations with model monomers initiated by BP/trithiane couples were followed by isothermal differential scanning calorimetry (DSC). The kinetics of these polymerizations were compared with the photochemical information on the quenching of excited BP by the trihianes. The polymerization efficiency using the various coinitiators did not follow the efficiency of photo-induced formation of the initiating radicals. The reasons for this lack of correlation were discussed in terms of the various factors that influence the polymerization aside from the efficiency of radical formation.

Słowa kluczowe

EN

benzophenone; initiation mechanism; photoreduction; radical photopolymerization; sulfides

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2000
• Tom: Vol. 45, nr 1
• Strony: 83--91
• Opis fizyczny: Bibliogr. 24 poz., rys.

Twórcy

autor

Andrzejewska E.

autor

Hug G.

autor

Andrzejewski M.

autor

Marciniak B.

• Institute of Chemical Technology and Engineering, Poznan University of Technology, M. Curie-Sklodowskiej 2, 60-965 Poznan, Poland