title: Potassium fulvate as co-interpenetrating agent during graft polymerization of acrylic acid from cellulose.
abstract: Grafting polymerization of acrylic acid onto cellulose in presence of potassium fulvate (KF) as a co-interpenetrating agent results enhanced water sorption compared to materials prepared similarly in its absence. The insertion of potassium fulvate (KF) did not affect the grafting process and is thought to proceed in parallel to the graft polymerization via intensive polycondensation reactions of its function groups (-COOH and OH) with COOH of the monomer and OH groups of cellulose. The combination of graft copolymerization and polycondensation reactions is assumed to produce interpenetrating network structure. Fourier transform infrared (FTIR) confirmed successful incorporation within the network structure which is an evidence for formation of interpenetrating network. The obtained structures showed homogeneous uniform surface as revealed by scanning electron microscopy (SEM). The obtained superabsorbent possessed high water absorbency 422 and 48.8g/g in distilled water and saline (0.9wt.% NaCl solution), respectively, and enhanced water retention even at elevated temperatures as revealed by thermogravimetric analysis (TGA). This could be explained by the high content of hydrophilic groups. The new superabsorbents proved to be efficient devices for controlled release of fertilizers which expands their use in agricultural applications.
authors.affiliation: Department of Chemistry, Faculty of Science, Al- Azhar University, Naser city, Cairo, Egypt.
authors.forename: Mohamed B M
authors.initials: MB
authors.lastname: Ghazy
authors.affiliation: Department of Chemistry, Faculty of Science, Al- Azhar University, Naser city, Cairo, Egypt.
authors.forename: Farag Abd
authors.initials: FA
authors.lastname: El-Hai
authors.affiliation: Department of Chemistry, Faculty of Science, Al- Azhar University, Naser city, Cairo, Egypt.
authors.forename: Magdy F
authors.initials: MF
authors.lastname: Mohamed
authors.affiliation: Department of Polymers and Pigments, National Research Centre, Dokki 12622, Cairo, Egypt. Electronic address: hessawy@hotmail.com.
authors.forename: Hisham A
authors.initials: HA
authors.lastname: Essawy
mesh_terms: D065966:Absorption, Physicochemical; D000178:Acrylamides / Q000737:chemistry; D000179:Acrylates / Q000737:chemistry*; D001578:Benzopyrans / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D005308:Fertilizers; D058105:Polymerization; D012987:Soil / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000178:Acrylamides; D000179:Acrylates; D001578:Benzopyrans; D005308:Fertilizers; D012987:Soil; D014867:Water; D002482:Cellulose; C021221:N,N'-methylenebisacrylamide; C036658:acrylic acid; C005023:fulvic acid
keywords: Acrylic acid; Cellulose; Controlled release; Grafting; Potassium fulvate; Soil fertilizers; Superabsorbents