Oligomerisation of hydroxymethacrylates via Michael-type addition

Attempts to conduct step-growth addition polymerisation of monomethacrylates of oligoethylene glycols via Michael-type addition of hydroxyl groups to carbon–carbon double bonds are presented. In the presence of several basic, nucleophilic and acidic reagents, disproportionation to corresponding glycols and dimethacrylates has been observed while some of them were found to initiate oligomerisation according to afore-said mechanism. Optimal reaction conditions have been established. The most effective initiators, i.e. potassium tert-butoxide and sodium hydride were selected to obtain the series of oligomers. The products were characterised by 1H NMR, GPC and ESI-MS to confirm oligo(ether–ester) structure and to estimate molecular weight. The latter appeared to be in order of one thousand.