Synthesis and characterization of some copolymers of N-vinylpyrrolidone with N-substituted maleimides and bismaleimides

Copolymers of N-vinylpyrrolidone (NVP) with N-substituted maleimides (RMIs) and bismaleimides (BMIs) have been prepared by free radical polymerization using 2,2-'zobisisobutyronitrile (AIBN) as initiator. The monomers used are (i) N-(4-methyl phenyl) maleimide (NMPM), (ii) N-(2-naphthyl) maleimide (NBNM), (iii) 4,4'-bismaleimido diphenyl methane (BMDPM) and (iv) p-phenylene bismaleimide (PPBM). The copolymers were characterized by IR and H-1 NMR spectroscopy. Their solubility in different solvents and intrinsic viscosity have been determined. Thermal stability of the copolymers was checked by thermogravimetric analysis (TGA) and differential thermogravimetry (DTG). The reactivity ratio values of the monomers in each copolymer have been determined by Fineman-Ross and Mayo-Lewis methods.