Synthesis and characterization of a novel Hydroxamic acid based polymer
Alaa Ismail Khalil Asaad
الاء إسماعيل خليل اسعد
Water-insoluble polymers based on hydroxamic acids are becoming increasingly im-portant in their applications for their impressive chelating ability with heavy metals. In this study, N1,N3-dihydroxymalonamide monomer was produced by reacting diethyl malonate with hydroxylamine hydrochloride using potassium hydroxide as a base in methanol. Then this monomer, N1,N3-dihydroxymalonamide, was reacted with α,α′-Dibromo-p-xylene in DMF at 60 °C with stirring overnight to produce a condensation polymer. The average molecular weight of this polymer was determined by static light scattering to be 728,000 g/mol. The glass transition temperature (Tg) and the melting point (Tm) were determined using DSC, their values were 73 °C and 148 °C, respec-tively. The polymer was partially soluble in dichloromethane and insoluble in water and in DMF. In addition, when the polymer's ability to chelate with chromium ions Cr(VI) was investigated, it was discovered that 1.0 g of polymer could remove 21% of Cr(VI) at pH=3 .