Hyperbranched polyglycerols exceeding M_n > 15,000 g/mol (DP_n > 270) have been prepared, using a modified version of the synthetic protocol reported earlier. In the optimized process polydispersities recorded by SEC remained narrow, with M_w/M_n < 1.7 over a large molecular weight range. The drastic increase of viscositity in the course of the reaction, was found to be responsible for the increased fraction of cycles (MALDI-TOF MS) at high molecular weights.
展开▼