title: Surface characteristics of polyhedral oligomeric silsesquioxane modified clay and its application in polymerization of macrocyclic polyester oligomers.
abstract: Novel porous aminopropyllsooctyl polyhedral oligomeric silsesquioxane (POSS) modified montmorillonite clay complexes (POSS-Mts) with large interlayer distance and specific surface area have been successfully prepared via ion-exchange reaction and followed by freeze-drying treatment. The morphology of the POSS-Mts is highly influenced by the POSS concentration, pH of the suspension and drying procedure, but the interlayer distance of the POSS-Mts does not change much when the POSS concentration is above 0.4 CEC. The POSS-Mts were used as Sn-catalyst supporters to initiate the ring-opening polymerization of cyclic butylene terephthalate oligomers (CBT) for the first time. No diffraction peak was detected by wide-angle X-ray diffraction for the polymerized composites (pCBT/POSS-Mt), even at 10 wt % loading of POSS-Mt. A clay network rather than exfoliation structure was observed unexpectedly in the composites by transmission electron microscopy. The pCBT/POSS-Mt composite with 10 wt % POSS-Mt was further melt-compounded with commercial PBT resin as a master batch. The tensile properties of the resultant PBT/POSS-Mt composites were highly improved as compared to the pristine PBT due to the homogeneous dispersion of POSS-Mt in the PBT matrix.
authors.affiliation: Institute of Polymer Technology & Materials Engineering, Loughborough University, Leicestershire, UK, LE11 3TU.
authors.forename: Chaoying
authors.initials: C
authors.lastname: Wan
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Xujin
authors.initials: X
authors.lastname: Bao
authors.forename: Bala
authors.initials: B
authors.lastname: Kandasubramanian
authors.forename: Matt
authors.initials: M
authors.lastname: Duggan