Polymer Bulletin, Vol.70, No.11, 3185-3200, 2013
Functional copolymer/organo-MMT nanoarchitectures: self-assembled core-shell morphology of poly(maleic anhydride-alt-alpha-olefin)/organo-MMT nanocomposites
This work describes the TEM morphology analysis of amphiphilic alternating copolymers of maleic anhydride (MA) with different alpha-olefins (1-hexene, 1-octene, 1-dodecene) synthesized by radical-initiated intercalative copolymerization of preintercalated MA center dot center dot center dot organoclay complexes in the presence of two types of organoclay such as reactive octadecyl amine-montmorillonite (ODA-MMT) and nonreactive dimethyldidodecyl ammonium-MMT (DMDA-MMT). TEM analyses of all the nanocomposites indicate the formation of symmetric or non-symmetric core-shell morphologies. Energy dispersive X-ray spectroscopy analyses were used to study the occurrence of the element in the poly(MA-alt-alpha-olefin)/organo-montmorillonite nanocomposites. A role of surfactant in these nanosystems insists on alternating copolymer segments with given hydrophobic/hydrophilic balance and surface organo-modifiers of MMT clays. Highly organized self-assembly with symmetric core-shell morphology were formed in nanosystems prepared in the presence of DMDA-MMT clay as compared with ODA-MMT clay-containing nanosystems. The relatively long branched olefin fragments significantly improve image parameters of core-shell morphology where some of the core structures contain accumulated and finely dispersed silicate particles at nano level around 2-25 nm. This observed phenomenon has brought a new approach for future utilization of these nanosystems in controlled drug delivery and anticancer applications with essentially prolonged activity.