Functional copolymer–clay hybrids were synthesized by radical-initiated intercalative copolymerization of maleic acid (MA) and acrylamide (AAm) with 2,2’-azobis (2-methylpropionamidine) dihydrochloride as a water-so...Functional copolymer–clay hybrids were synthesized by radical-initiated intercalative copolymerization of maleic acid (MA) and acrylamide (AAm) with 2,2’-azobis (2-methylpropionamidine) dihydrochloride as a water-soluble ionizable radical initiator in the presence of reactive (octadecyl amine (ODA)-MMT) and non-reactive (dimethyldodecyl ammonium (DMDA)-MMT) organoclays at 50oC in aqueous medium under nitrogen atmosphere. The monomers was dissolved in aqueous medium, as well as both used clay particles were easily dissolved and dispersed with partially swollen in deionized water, respectively. Structure, thermal behavior and morphology of the synthesized nanocomposites were investigated by FTIR, XRD, DSC-TGA, SEM and TEM analysis methods, respectively. It was demonstrated that intercalative copolymerization proceed via ion exchange between organoclays and carboxylic groups of monomers/polymers which essentially improved interfacial interaction of polymer matrix and clay layers through strong H-bonding. In case of intercalative copolymerization in the presence of ODA-MMT clay, similar improvement was provided by in situ hydrogen-bonding and amidolysis of carboxylic/anhydride groups from copolymer chains with primary amine group of ODA-MMT. The nanocomposites exhibit higher intercalation/exfoliation degree of copolymer chains, improved thermal properties and fine dispersed morphology.展开更多
基金financial supports via MS and PhD bursarsthe Turkish Scientific and Technology Research Council(TUBITAK)for the financial support of this work through project TBAG-HD/249.
文摘Functional copolymer–clay hybrids were synthesized by radical-initiated intercalative copolymerization of maleic acid (MA) and acrylamide (AAm) with 2,2’-azobis (2-methylpropionamidine) dihydrochloride as a water-soluble ionizable radical initiator in the presence of reactive (octadecyl amine (ODA)-MMT) and non-reactive (dimethyldodecyl ammonium (DMDA)-MMT) organoclays at 50oC in aqueous medium under nitrogen atmosphere. The monomers was dissolved in aqueous medium, as well as both used clay particles were easily dissolved and dispersed with partially swollen in deionized water, respectively. Structure, thermal behavior and morphology of the synthesized nanocomposites were investigated by FTIR, XRD, DSC-TGA, SEM and TEM analysis methods, respectively. It was demonstrated that intercalative copolymerization proceed via ion exchange between organoclays and carboxylic groups of monomers/polymers which essentially improved interfacial interaction of polymer matrix and clay layers through strong H-bonding. In case of intercalative copolymerization in the presence of ODA-MMT clay, similar improvement was provided by in situ hydrogen-bonding and amidolysis of carboxylic/anhydride groups from copolymer chains with primary amine group of ODA-MMT. The nanocomposites exhibit higher intercalation/exfoliation degree of copolymer chains, improved thermal properties and fine dispersed morphology.
