부산대학교 도서관

Novel copolycarbonates containing 1,4:3,6-dianhydro-D-glucitol or 1,4:3,6-dianhydro-D-mannitol units, with various methylene chain lengths, were synthesized by bulk and solution polycondensations, of several combinations of carbonate-modified sugar derivatives and aliphatic diols. Bulk polycondensations of 1,4:3,6-dianhydro-2,5-bis-O-(phenoxycarbonyl)-D-glucitol or 1,4:3,6-dianhydro-2,5-bis-O-(phenoxycarbonyl)-D-mannitol with four α,ω-alkanediols having methylene chain lengths of 4, 6, 8, and 10, respectively, at 180 °C afforded the corresponding copolycarbonates with number-average molecular weight (Mn) values up to 19.2 × 10³. ¹³C NMR analysis disclosed that these polymers had scrambled structures in which the sugar carbonate and aliphatic carbonate moieties were nearly randomly distributed along a polymer chain. However, solution polycondensations between 1,4:3,6-dianhydro-2,5-bis-O-(p-nitrophenoxycarbonyl)-D-glucitol or 1,4:3,6-dianhydro-2,5-bis-O-(p-nitrophenoxycarbonyl)-D-mannitol, and the α,ω-alkanediols in sulfolane or dimethyl sulfoxide at 60 °C gave well-defined copolycarbonates having regular structures consisting of alternating sugar carbonate and aliphatic carbonate moieties with Mn values up to 33.8 × 10³. Differential scanning calorimetry demonstrated that all the copolycarbonates were amorphous with glass-transition temperatures ranging from 1 to 65 °C, which decreased with increasing lengths of the methylene chain of the aliphatic diols. Additionally, all the copolycarbonates were stable up to 310–330 °C as estimated by thermogravimetric analysis. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2312–2321, 2003