POLYMERIZATION OF 2,2-DIMETHYLTRIMETHYLENE CARBONATE WITH TRI-SEC-BUTOXYALUMINIUM - A KINETIC-STUDY

The polymerization of 2,2-dimethyltrimethylene carbonate (DTC, 1) with tri-sec-butoxyaluminium (Al(O-SeC-Bu)3) Proceeds with suppression of macrocyclics formation. The propagation of the polymerization proceeds pseudoanionically via insertion. Within the scope of a kinetic treatm ent, the time-conversion relationship was determined for the polymeriz ation of DTC with Al(O-sec-Bu)3 as initiator and toluene as solvent. F or a polymerization temperature between 15-degrees-C and 74-degrees-C, the apparent rate constant was found to be between 0,1 and 1,0 L.mol- 1.s-1. Using the Arrhenius plot the experimental temperature coefficie nt (20,6 kJ . mol-1) as well as the frequency factor of the polymeriza tion (1,3 . 10(3) L.mol-1.s-1) were determined. Investigation of the d ependence of the rate of polymerization on the initiator concentration revealed a degree of aggregation of 2 for the active species.