Poli (itakonik asit-co-stearil metakrilat-co-akrilamit) hidrojellerinin sentezi, karakterizasyonu ve metilen mavisi ile kristal violet boyar maddelerinin adsorpsiyonundaki uygulamaları Synthesis and characterization of poly (itaconic acid-co-stearyl methacrylate-co-acrylamide) hydrojels and applications of the hydrogels in methylene blue and crystal violet adsorption