Mechanism of the polymerization of trifluoroacetaldehyde initiated by azobisisobutyronitrile

Abstract The polymerization of fluoral initiated by the photolyzed decomposition of azobisisobutyronitrile at low temperature has been studied. Up to 2% conversion, the effect of radical scavengers and the order with respect to initiator and light intensity indicate that the reaction occurs by a conventional radical polymerization mechanism. At about 2% conversion autoacceleration sets in and the rates become irreproducible. This is explained by typical occlusion phenomena. Tracer studies show that polymer prepared at high conversion contains initiator fragments indicating that primary propagation is by monomer addition to radicals. The reaction mechanism is discussed.