Thakur KA1, Kean RT, Hall ES, Doscotch MA, Munson EJ.
Anal Chem. 1997 Nov 1;69(21):4303-9. doi: 10.1021/ac970792o.A method has been developed to quantitatively determine the composition of d-lactide and meso-lactide stereoisomer impurities in poly(lactide) containing predominantly l-lactide. In this method, the stereosequence information obtained from a few well-resolved resonances in the (1)H NMR spectrum representing RR and R stereogenic defects is used. The d-lactide and meso-lactide as minor components lead to RR and R stereogenic defects, respectively, which influence the isotactic chain length distribution and hence affect the polymer properties. Read More