Method for preparing functionalized polymers from polymer alcohols

摘要

Disclosed is a method for forming functionalized polymers from polymer alcohols, comprising: (a) a water-soluble and non-peptidic polymer comprising two hydroxyl groups; (b) reacting the water-soluble and non-peptidic polymer comprising two hydroxyl groups, in one or more reaction steps, with one or more functionalizing reagents that are reactive with a hydroxyl group to effect the introduction of a functional group, Y, to form a mixture comprising: (i) an unsubstituted water-soluble and non-peptidic polymer from step (a), (ii) a monosubstituted polymer comprising a single Y group, and (iii) a disubstituted polymer comprising two Y groups, under conditions effective to form: (i) from 8 to 45 percent of the monosubstituted polymer; and (ii) no more than 40 percent of the disubstituted polymer; and (iii) a ratio of monosubstituted polymer to disubstituted polymer that is 2:1 to 40:1; and (c) purifying the mixture from step (b) to provide a monosubstituted polymer substantially free from the unsubstituted and disubstituted polymer species.