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Alditol-based polyesters

For the last few years, Kobayashi s and Gross s groups have been independently working on the synthesis of alditol-based polyesters by lipases as catalysts for selective polyol polymerizations. Lipases and proteases are well known as providing regioselectivity during esterification reactions at mild temperatures. In addition to this, the use of... [Pg.97]

Galbis et al. described a variety of carbohydrate-based linear polyesters 61 of the poly(alkylene dicarboxylate) type that were obtained by polycondensation reactions of the alditols 2,3,4-tri-(9-methyl-L-arabinitol (9) and 2,3,4-tri-O-methyl-xylitol (10), and the aldaric acids 2,3,4-tri-(9-methyl-L-arabinaric acid (26) and 2,3,4-tri-(9-methyl-xylaric acid (27), butanediol, and adipic acid were also used as comonomers [28]. Copolyesters of the poly(aIkylene-c )-arylene dicarboxylate) type were obtained using bisphenols as comonomers (Scheme 1). Chemical polycondensation reactions were conducted in bulk or in solution. Enzymatic polycondensation reactions of adipic acid with the above-mentioned alditols were carried out successfully using Lipozyme and Novozyme 435. The hydrolytic degradations of some of these polyesters were also described. [Pg.154]

Anhydro-alditols - The preparations of polyesters based on l,4 3,6-di-anhydro-D-glucitol and -o-mannitol with succinyl-, glutaryl- and adipoyl-dichlor-ides have been reported. Also reported have been the syntheses of poly(1 6)-2,5-anhydro-D-glucitol and its 3,4-di-0-alkylated derivatives by Lewis acid induced polymerization of 3,4-di-0-alkyl-l,2 5,6-dianhydro-D-mannitol base induced polymerization of l,2 5,6-dianhydro-3,4-di-0-methyl- or 3,4-di-O-iso-propylidene-D-mannitol base induced polymerization of l,2 5,6-dianhydro-3,4-di-O-pentyl- or di-O-decyl-o-mannitol and base induced polymerization of l,2 5,6-dianhydro-3,4-di-0-methyl-L-iditol. The solubilities of these 3,4-di-O-alkylated and deprotected polymers in aqueous and organic media were studied. Further, it has been reported that 2,5-anhydro-3,4-di-0-methyl-D-glucitol linked 1,6 to silica gel was useful for the optical resolution of amines and amino acid salts. ... [Pg.226]


See other pages where Alditol-based polyesters is mentioned: [Pg.156]    [Pg.156]    [Pg.158]   
See also in sourсe #XX -- [ Pg.97 ]




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