The present invention relates to an ionic multi-block copolymer
composition comprising tri-block copolymers having a polypropyleneoxide
or polybutyleneoxide block positioned between two polyethyleneoxide
blocks and the tri-block copolymers are connected through dicarboxylic
acid linkages forming a multi-block copolymer having a weight average
molecular weight of more than 40,000 Dalton. The higher weight average
molecular weight enables the hydrolgel formed from the multi-block
copolymer of the present invention to maintain its gel status for more
than several days.