Radical polymerization of ethyl α-benzoyloxymethylacrylate in benzene

✍ Scribed by T. Sato; I. Kamiya; H. Tanaka; T. Ota

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 351 KB
• Volume: 27
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(91)90084-2

✦ Synopsis

The polymerization of ethyl ~t-benzoyloxymethylacrylate (EBMA), an ct-disubstituted monomer, initiated with azobisisobutyronitrile (AIBN) was studied kinetically in benzene. The polymerization rate (Rp) at 60 ° was expressed by Rp = k[AIBN] °'5 [EBMA] t'6. The overall activation energy was calculated to be 53 kJ/mol. Rate constants of propagation (kp) and termination (kt) of EBMA were estimated as 990 and 2.9 x 10 6 I/mol. sec respectively at 60 °, using the ESR-determined concentration of the propagating polymer radical. The large kp and rather low k t led to formation of poly(EBMA) with high molecular weight (A'Tn= 1-5 x 105). Thermogravimetry revealed that thermal degradation of poly(EBMA) began near 300 ° and the residue at 500 ° was only 2% of the initial polymer. Copolymerization of EBMA (M ~ ) with St (M 2) was also examined at 60 ° in benzene. The following copolymerization parameters were obtained according to the Kelen-Tiid6s method; r t = 0.27 + 0.01, r 2 = 0.30 + 0.02 giving Qi = 0.93 and e~ = +0.78.