title: Grafting of poly[(methyl methacrylate)-block-styrene] onto cellulose via nitroxide-mediated polymerization, and its polymer/clay nanocomposite.
abstract: For the first time, nitroxide-mediated polymerization (NMP) was used for synthesis of graft and block copolymers using cellulose (Cell) as a backbone, and polystyrene (PSt) and poly(methyl metacrylate) (PMMA) as the branches. For this purpose, Cell was acetylated by 2-bromoisobutyryl bromide (BrBiB), and then the bromine group was converted to 4-oxy-2,2,6,6-tetramethylpiperidin-1-oxyl group by a substitution nucleophilic reaction to afford a macroinitiator (Cell-TEMPOL). The macroinitiator obtained was subsequently used in controlled graft and block copolymerizations of St and MMA monomers to yield Cell-g-PSt and Cell-g-(PMMA-b-PSt). The chemical structures of all samples as representatives were characterized by FTIR and (1)H NMR spectroscopies. In addition, Cell-g-(PMMA-b-PSt)/organophilic montmorillonite nanocomposite was prepared through a solution intercalation method. TEM was used to evaluate the morphological behavior of the polymer-clay system. It was demonstrated that the addition of small percent of organophilic montmorillonite (O-MMT; 3wt.%) was enough to improve the thermal stability of the nanocomposite.
authors: Department of Chemistry, Payame Noor University, P.O. Box: 19395-3697 Tehran, Islamic Republic of Iran.
authors: Saber Ghasemi
authors: SG
authors: Karaj-Abad
authors: Department of Chemistry, Payame Noor University, P.O. Box: 19395-3697 Tehran, Islamic Republic of Iran. Electronic address: m_abbasian20@yahoo.com.
authors: Mojtaba
authors: M
authors: Abbasian
authors: Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, P.O. Box: 51656-65811, Tabriz, Islamic Republic of Iran. Electronic address: m_jaymand@yahoo.com.
authors: Mehdi
authors: M
authors: Jaymand
mesh_terms: D000538:Aluminum Silicates / Q000138:chemical synthesis / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D000077215:Clay; D046911:Macromolecular Substances / Q000138:chemical synthesis* / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry; D009589:Nitrogen Oxides / Q000737:chemistry*; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011137:Polystyrenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D046911:Macromolecular Substances; D009589:Nitrogen Oxides; D011108:Polymers; D011137:Polystyrenes; D002482:Cellulose; D019904:Polymethyl Methacrylate; C039900:nitroxyl; D000077215:Clay
keywords: Cellulose; Chemical modification; Clay; Copolymer; Nanocomposite; Nitroxide-mediated polymerization