Morphology, mechanical property, and processing thermal stability of PVC/La-OMMTs nanocomposites prepared via in situ intercalative polymerization

Poly(vinyl chloride) (PVC) nanocomposites were prepared via an in situ intercalative suspension polymerization of vinyl chloride with four organic carboxylic acid salts (montmorillonite [MMT] units) containing thermally stable lanthanum ions. The effects of different lanthanum organic montmorillonites (La-OMMTs) on the particle features and molecular weight were investigated. The transmission electron microscopy data indicated the formation of partially exfoliated or intercalated PVC/La-OMMTs nanocomposites. The effect of different functional groups on the mechanical properties and processing thermal stability of PVC/La-OMMT nanocomposites were investigated. Tensile testing and two-roll mill processing results showed that La-OMMTs could enhance the dynamic thermal stability and mechanical properties versus PVC pure resin and PVC/I.30P nanocomposites (composed of PVC and I.30P). This suggested that the double bond and amidogen group in La-OMMTs could promote the dispersion of La-OMMTs in the PVC matrix and also improve the adhesion between the La-OMMTs and PVC matrix. The results have potential value in the industrial development of PVC/La-OMMTs nanocomposites. J. VINYL ADDIT. TECHNOL., 26:97–108, 2020. © 2019 Society of Plastics Engineers