2 ethyl hexyl acetate naphthalene and octane for example the polymerization can be carried out in orthodichlorobenzene at a temperature between about 7 u00b0 c and about 180 u00b0 c in a most preferred embodiment r 1 is ethyl and polymer i has a number average molecular weight of about 50 000 this poly 2 ethyl 2 oxazoline polymer is sold commercially under the name of aquasol 50 by polymer chemistry innovations inc the assignee of this application to form the mechanically crosslinkable polymeric hydrogel of the present invention up to about 20 of the pendent r 1 groups on polymer i are replaced by a water soluble polymer to form a graft copolymer of structure ii the water insoluble polymer portion of graft copolymer ii is a non water soluble polymeric material having a number average molecular weight between about 5 000 and 100 000 preferably between about 8 000 and about 20 000 and most preferably between about 10 000 and 15 000 the water insoluble polymer includes polyethylene long chain alkyl polypropylene polybutadiene polyisoprene polystyrene polymethylacrylate polymethylmethacrylate polyurethanes polyamides polyesters polyesteramides and copolymers of same in a first embodiment graft copolymer ii is formed by a transamidation reaction in general transamidation is accomplished by.