A new hybrid nanocomposite prepared by emulsion copolymerization of ABS inthe presence of clay

The preparation and characterizations of new hybrid organic-inorganic nanoc omposites consisting of acrylonitrile-butadiene-styrene terpolymer and a Na +-exchanged montmorillonite (MMT) are described by direct intercalation thr ough onestep emulsion polymerization. Those products were purified by succe ssive hot acetone and toluene extraction, respectively, for more than 2 day s. The IR spectra for the purified samples revealed the characteristic abso rbances as a result of those of styrene, butadiene, acrylonitrile, and MMT. X-ray diffraction spectra of the composites showed the enlarged 001 d-spac ing as much as 1.75 nm, but no signals were found for the partial insertion of copolymer chains. Moreover, it was evident that this direct intercalati on was not accompanied by delamination of the clay interlayer. The thermogr avimetric analytic measurement for the purified product confirmed that the onset temperature of decomposition was transferred to the higher temperatur e region as much as 40-50 degreesC. Morphological observations by transmiss ion electron microscopy, scanning electron microscopy, and optical microgra phy demonstrated homogeneous dispersion of MMT particles in the copolymer m atrix. The possible physical picture of this direct intercalation was discu ssed in terms of swelling characteristics of compacted bentonite and the mo nomer containing micelle sizes. (C) 2001 John Wiley & Sons, Inc.