Ring‐opening Polymerization of D,L‐Lactide by Lanthanide Tris(2,4,6‐trimethylphenolate): Characteristics and Kinetics

Abstract

Tris(2,4,6-trimethylphenolate) lanthanide [Ln(OTMP) 3 ] has been prepared and employed for ring-opening polymerization of D,L-lactide (LA) as single-component catalysts. The characteristics, kinetics and mechanism were examined. The polymerization is first-order with respect to monomer and initiator concentration, and the overall activation energy amounts to 62.9 kJ/mol. DSC curve disclosed the random structure of PLA. 1 H NMR spectrum analysis demonstrates that the polymerization of LA proceeded through acyl-oxygen bond cleavage.

Mechanism of ring‐opening polymerization of l‐lactide by lanthanide aryloxide: A theoretical study on the effect of the aryloxide ligands on the process

“…More polar solvents can decrease the activation energies significantly (Table S3). The results also suggest that La(OTMP) 3 is a low-active initiator for LLA ROP, which support experimental observations for the broadening of molecular weight distribution in the lactide ROP mediated by La(OAr) 3 -type initiators [6,26,38,46].…”

“…The solvent effect was studied on the reaction of interest using the SMD continuum solvation model [37] upon the geometries along the minimum energy pathway. In the SMD calculations, toluene ( ε = 2.37) was used as the solvent and simulated at 90°C (or 363.15 K), corresponding to the experimental conditions [38]. Hirshfeld charge [39] and HOMO‐LUMO analysis were performed using the same functional and basis set as geometry optimizations.…”

Optimal Weighted Least Square Data Fusion Method for Redundant IMU Based on Calculation of Measurement Error

“…Skoogh Daniel proposed a fault detection method of redundant INS in [3]. Hua Bing suggested an error calibration method for redundant INS in [4]. Yang Cheol-Kwan suggested a use of least square data fusion method for redundant INS in [5] which is not an optimal method regretfully.…”