The modification of lanthanum-exchanged montmorillonite with anionic surfactants to enhance the thermal stability of polyvinyl chloride

A series of thermally stable lanthanum organic montmorillonites (La-OMMTs) were successfully prepared by modifying Na-MMT with anionic surfactants and lanthanum chloride. Fourier transform infrared spectroscopy and X-ray diffraction indicated that the anionic surfactants resided in the interlayer spaces and expanded the MMT basal spacing from 1.23 nm to 3.3 nm. Thermogravimetric and differential thermal analysis (TG/DTA) results showed that the intercalation of sodium dodecyl sulfonate into the lanthanum organic MMT resulted in its excellent thermal stability. The use of the La-OMMT samples in polyvinyl chloride (PVC) resins was tested, and the TG/DTG results revealed that the three La-OMMTs could significantly enhance the thermal stability of PVC. The modified La-OMMT with the highest thermal stability is expected to be useful in polymer/layered silicate nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41535.