ISSN:
0887-624X
Schlagwort(e):
copolymerization
;
charge transfer complex
;
cyclization
;
allyl acrylate
;
allyl methacrylate
;
maleic anhydride
;
chain growth reactions
;
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Radical copolymerization of allyl acrylate (AA) and allyl methacrylate (AMA) as bifunctional monomers of donor (allyl)-acceptor (acryl) type with maleic anhydride (MA) as an acceptor monomer were carried out in metrhyl ethyl ketone (MEK) at 50-70°C in the presence of 2,2′-azoisobutyronitrile (AIBN) as initiator. Constants of complex formation (Kc), cyclization (kcl), and copolymerization (r1, r2, r1c, r1c1, and r1c2) as well as energies of activation for cyclization (Eac) and copolymerization reactions (Ea), and orders for the monomer (m) and initiator (n) concentrations were determined. The following values were found, for AA and AMA, respectively: Kc = 0.038 and 0.11 L/mol in deutered acetone at 35 ± 0.1°C, kcl = 6.45 and 6.53, r1 = 0.083 ± 0.005 and 0.028 ± 0.002, r2 = 0.027 ± 0.002 and 0.063 ± 0.003 (by the Kelen-Tüdös method), r1c = 0.04 and 0.025, r1c1 = 0.128 and 0.176, r1c2 = 0.127 and 0.177 (by the Seiner-Litt equation), Eac = 28.9 and 28.7 kJ/mol, Ea = 67.0 and 87.9 kJ/mol, m = 1.53 and 1.45, and n = 0.50 and 0.52. The presence of cyclic, unsaturated, and anhydride fragments in the macromolecules was confirmed with FTIR data and chemical (iodometrical and potentiometric titrations) analysis. It was established that complex formation in the monomer systems studied is the main factor for alternating cyclocopolymerization leading to formation of copolymers containing lactone and linear-unsaturated fragments in the macromolecular chain. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1501-1508, 1998
Zusätzliches Material:
4 Ill.
Materialart:
Digitale Medien
Permalink
