A water-soluble poly (tetra(2-hydroxy-3-(methacrylo yloxy)propyl)benzene-1,2,4,5-tétracarboxylate-co-ac rylamide) (poly (HMBC-co-AM)) has been synthesized by free ra dical polymerization of tetrafunctional methacrylat e macromonomer named tetra( 2-hydroxy-3-(methacryloyl oxy)benzene-1,2,4,5-tetracarboxylate (HMBC) and acrylamide (AM) in THF solution at 80°C employed AI BN as an initiator. The HMBC was synthesized by dir ect addition reaction between the glycidyl methacrylate (GMA) and pyromellitic dianhydride (PMDA) in aceto ne in the presence of Maghnite-H + as a catalyst at room temperature (20°C). The Magh nite-H + is a proton exchanged montmorillonite clay. The HMBC and poly (HMBC-co-A M) were characterized by FT-IR, 1 H NMR and 13 C NMR spectroscopic techniques. The molecular weights and polydispersity index of the HMBC were determined e mployed gel permeation chromatography GPC. The thermal ana lysis of the poly (HMBC-co-MA) was performed by thermogravimetric analysis (TGA) and DSC.