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Alternating Copolymerization and Copolymers of Styrene and N-(2,4-Dibromoplienyl)maleimide

Zvonimir Janović ; Faculty of Chemical Engineering and Technology, University of Zagreb, Zagreb, Croatia
Nevenka Rak ; Faculty of Chemical Engineering and Technology, University of Zagreb, Zagreb, Croatia

Sažetak

Free radical copolymerization of styrene (St) and AT-(2,4-dibromo- phenyllmaleimide (DBPMI) in dioxane solution gave an alternating copolymer in all proportions of feed comonomer compositions. The copolymerization reactivity ratios were found to be rx = 0.049 ± 0.0023 (St) and r2 = 0.0115 ± 0.0018 (DBPMI); Q and e values were also calculated. The molecular weights of the copolymers obtained are relatively high and the alternating copolymer had a glass transition temperature of 507 K: the thermal stability of the copolymer is higher than that of polystyrene.
The equilibrium constant of charge-transfer complex of St and DBPMI was determined by 'H-NMR spectroscopy in deuterated chloroform and gave a value of 0.12 L/mol. The initial rate of copolymerization was measured as a function of the monomer ratios, and the participation of the charge-transfer complex monomer and the free monomers was quantitatively estimated. It was established that the copolymerization of St with DBPMI proceeds predominasntly through participation of the free monomers.

Ključne riječi

Hrčak ID:

136774

URI

https://hrcak.srce.hr/136774

Datum izdavanja:

1.12.1994.

Posjeta: 831 *