Research Article
Cyclic Oligolactic Acid in Direct Polycondensation PLLA and Its Extraction with Organic Solvent
Figure 2
ESI-MS spectra of products extracted with (a) methanol (r.t.), (b) hexane (r.t.), and (c) hexane (4°C). [L5 + Na]+ is due to the Na+ adduct of l-OLLA with , and [C8 + K]+ is due to the K+ adduct of c-OLLA with .
| (a) |
| (b) |
| (c) |