H. Nakamura, M. Seno, H. Tanaka
Feb 1, 1995
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0
Influential Citations
4
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Journal
Colloid and Polymer Science
Abstract
The polymerization of di-2[2-(2-methoxyethoxy)ethoxy]ethyl itaconate (1) with dimethyl 2,2′-azobisisobutyrate (2) was studied, in benzene, kinetically and spectroscopically with the electron paramagnetic resonance (EPR) method. The polymerization rate (Rp) at 50°C is given by the equation:Rp=k[2]0.48 [1]2.4. The overall activation energy of polymerization was calculated to be 34 kJ·mol−1. From an EPR study, the polymerization system was found to involve EPR-observable propagating polymer radicals of 1 under the actual polymerization conditions. Using the polymer radical concentration, the rate constants of propagation (kp) and termination (kt) were determined. With increasing monomer concentration,kp(1.5∼4.3 L·mol−1·s−1 at 50°C) increases andkt(1.0·104∼4.2·104 L·mol−1·s−1 at 50°C) decreases, which seems responsible for the high dependence ofRp on the monomer concentration. The activation energies of propagation and termination were calculated to be 11 kJ·mol−1 and 84 kJ·mol−1, respectively. For the copolymerization of 1(M1) and styrene (M2) at 50°C in benzene the following copolymerization parameters were found:r1=0.2,r2=0.53, Q1=0.57, ande1=+0.7.