Abstract: A a method for producing activated linear polymers and activatable branched polymers thereof, is carried out by a) reacting a linear nonpeptidic activatable polymer, chemically blocked at one end, with an azole ring activating group that provides a leaving group to produce an intermediate polymer of the general formula poly-lm; b) reacting said poly-lm with an alkylating agent to form an imidazolium salt of the general formula poly-1m+(alkyl)X-; and c) reacting said poly-lm +(alkyl)X with a linker molecule bearing at least two nucleophilic moieties to produce an activatable branched polymer derivative thereof. In some embodiments “poly” is a polymer selected from the group consisting of poly(alkylene oxides), poly(oxyethylated polyols), poly(olefinic alcohols), and polymers of alkylene oxide and propylene oxide; in some embodiments “Im +” is an imidazolium ion; and in some embodiments “X-” is an anionic counterion.