Crumpled highly filled poly(styrene-co-butyl acrylate)/clay hybrid latexes

The encapsulation of laponite in poly(styrene-co-butyl acrylate) nanoparticles to obtain hybrid latexes with ultra-high clay contents is described. In-situ intercalative ad-miniemulsion polymerisation was used to prepare these hybrid latexes facilitating encapsulation up to 50 wt% of laponite clay. The encapsulation of clay platelets resulted in latexes with crumpled particle morphology. Besides the polymerisation method, the encapsulation of clay was facilitated by careful choice modifier and use of non-dried modified clay. TEM and SAXS showed that the clay platelets were exfoliated and homogeneously distributed within the transparent polymer/clay nanocomposites films. The use of reactive clay modifier enhanced the clay exfoliation and polymer-clay interactions resulting in material showing significant storage modulus improved of up to 5000%. The high clay content incorporated was above the percolation threshold and the materials exhibited solid-like viscoelastic behaviour.