The melt intercalation of poly(L-lactide) (PLLA) chains into silicate galleries has been investigated via a melting process without any shearing force at elevated temperature. Under the melting process, the incorporation of various types of organo-modified montmorillonites into PLLA matrix lead to the increase in the basal spacing of clay particles in different manner without delamination into individual layers. The changes in layer-stacked structures of the clay particles in the PLLA matrix were examined by use of wide-angle X-ray diffraction and transmission electron microscopy. The effects of clay content in PLLA matrix and clay surfactants on the melt intercalation of PLLA were discussed in terms of chain mobility. (c) 2005 Published by Elsevier Ltd.