(510f) Analysis of Interfacial Action of Rectorite/thermoplastic Polyurethane Nanocomposites by Inverse Gas Chromatography and Molecule Simulation

The interfacial action plays an important effect in the structure and properties of the composite materials. So the dispersion of nano particle in polymer matrix and the interfacial integration of nano particle and polymer matrix make great contribution to make perfect nano/polymer composite materials. The analysis of interactions between filler and polymer not only provide a theoretical basis for the design of the composite interface , but also improve the application to fields such as catalyzer, environment and adsorption.

Rectorite (REC) is another kind of clay mineral , with structure and characteristics much like those of MMT. In this paper, REC is organomodified with two kind of quaternary ammonium salt(quat), then organomodified rectorite (OREC) /thermoplastic polyurethane (TPUR) named OREC/TPUR are prepared via melt blending. The structure model of REC, OREC, quat,and TPUR are built using technique of molecule simulation, interaction energy was calculated to analysis the interaction between REC and quaternary ammonium salt and polymer. We characterize the surface dispersive energy and the surface acid-base properties of REC,OREC,TPUR and the composites by Inverse gas chromatography(IGC). It is analyzed the correlation of the surface properties of REC,OREC,TPUR with the structure and mechanical properties of the composites. It is found that the binding energy between 1227 quat and REC which is higher than that between 1631 quat and REC. So the combination between 1227 quat and REC is more effective than 1631 quat and REC. The binding energy of REC and TPUR ,1227-OREC and TPUR ,1631-OREC and TPUR are 499,3650,2942(kJ/mol) respectively,that shows the combination between 1227-OREC and TPUR is also better than 1631-OREC.

The IGC results indicated that the surface dispersive energy was directly influenced by surface treatment. The values of 12-OREC and 16-OREC (24.85, 30.43 mJ/m2) were lower markedly than that of REC(75.19 mJ/m2) at 100 °C . In addition, the acid-base properties of REC also changed after treating. Quaternary ammonium salt modify the behavior of the acidic REC, resulting in a mainly basic surface.

It can found that the surface properties of REC directly affect the structure of the composite and make great contribution to a series of properties of composite materials. The modification of REC improving the dispersibility in TPUR .12-OREC is found to be the best dispersibility in TPUR and better mechanical properties of the composites because the dispersive energy and acid-base property are most comparable with that of the polymer matrix.

Study of nanocomposite with different loading of OREC show that the loading of OREC affect surface propertise of its nanocomposite,and when the loading of OREC is 5phr the breaking elongation reaches the highest value, which is associated with the well-interaction because of the lowest surface energy.