A series of group 3, 4 and 13 permethylindenyl chrloride, aryloxide, and borohydride complexes have been synthesised and fully characterised. Their activities for the ring-opening polymerisation (ROP) of L-, D-, meso- and rac-lactide have been tested. The ROP of L- and rac-lactide produced isotactic polylactide (PLA) and moderately heterotactic PLA (Pr = 0.68–0.72), respectively. Good agreement between experimental and theoretical molecular weights of PLA (Mn) and relatively narrow dispersities were obtained.
Few initiators displayed second order dependence on monomer concentration and produced isotactic and heterotactic (Pr = 0.81) polylactides for the polymerisation of L-, D- and rac-lactide respectively. The effects of temperature, catalyst concentration, co-initiator concentration, solvent and scale were studied.
“Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of L- and rac-lactide”. N. Diteepeng, J.-C. Buffet, Z. R. Turner and D. O’Hare, Dalton Trans., 2019, 48, 16099.
“Group 4 permethylindenyl complexes for the polymerisation of L-, D- and rac-lactide monomers”. J. V. Lamb, J.-C. Buffet, J. E. Matley, C. M. R. Wright, Z. R. Turner and D. O’Hare, Dalton Trans., 2019, 48, 2510.