ISSN:
0959-8103
Keywords:
copolymerization
;
charge-transfer complex
;
trans-stilbene
;
N-maleimide
;
N-ethylmaleimide
;
N-phenylmaleimide
;
structure
;
thermal degradation
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Radical copolymerization of donor-acceptor monomers, i.e. trans-stilbene (Stb) with N-maleimide (MI), N-ethylmaleimide (EtMI) and N-phenylmaleimide (PhMI), are studied. Constants of charge-transfer complex formation (Kc) and copolymerization (r1 and r2) are determined by Hanna-Ashbaugh (1H nuclear magnetic resonance) and Kelen-Tüdöş methods, respectively. The results obtained were analysed by use of the complex copolymerization model of Seiner-Litt. It is found that the tendency for complex formation and the tendency for alternation of monomers depend on the nature of the N-substituent in the maleimide molecule. Kc is found to increase in the order EtMI 〈 MI 〈 PhMI, and the tendency for alternation (r1 · r2) decreases in the order MI 〉 EtMI 〉 PhMI. It is shown by thermogravimetric analysis, differential thermal analysis and differential scanning calorimetry that the alternating copolymers synthesized have high thermostabilities. The copolymers synthesized show increased thermal stabilities, as well as glass transition temperatures, with the change of imide N-substituent. Stb-MI, Stb-EtMI and Stb-PhMI copolymers decompose through a one-step reaction at 456, 460 and 468°C, respectively.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
