Abstract: PLA /OMMT intercalation nanocomposite was synthesised by in-situ intercalation polymerization with organomontmorillonite (OMMT) and lactic acid monomer. The structure and morphology of PLA/OMMT intercalation nanocomposite were characterized by FT -IR , XRD，TEM. The degradability of PLA/OMMT intercalation nanocomposite was also studied. The FT –IR spectra indicated that the OMMT was exfoliated and dispersed into the PLA matrix during the polymerization. XRD shew that the layer spacings of MMT, OMMT and PLA/OMMT intercalation nanocomposite were 1.260nm, 1.993 nm and 2.287 nm individually, which shew the swellable silicate layers were intercalated by the PLA matrix, and in-situ intercalation polymerization was done. TEM images demonstrated that the PLA/OMMT intercalation nanocomposite was of intercalative structure, which accorded with the results of FT –IR and XRD. The results of the degradation of PLA/OMMT intercalation nanocomposite showed the media degradability rank was as following : NaOH>HCl>deionied water. In PBS buffer solution the intrinsic viscosity of PLA/OMMT intercalation nanocomposite was declined as the degrading time .It was shown that the degradability rate of PLA/OMMT intercalation nanocomposite was faster than that of PLA, which demonstrated that the degradability of PLA/OMMT intercalation nanocomposite was improved by the MMT 。

Key words: polylactic acid, organic montmorillonite, intercalation nanocomposite, synthesis, degradability