Preparation of PLLA-co-bis A ER/VMT Nanocomposites by In Situ Polymerization Process

ABSTRACT

Poly(L-lactic acid)-co-bisphenol-A epoxy resin/vermiculite nanocomposites (PLLA–co-bis A ER/VMT) were prepared by in situ melt polycondensation of L-LA in the presence of amino-modified vermiculite. The fourier transform infrared (FTIR) spectra was used to investigate molecular interactions between the modified vermiculite and PLLA. Transmission electron microscopy (TEM) testing indicated that the VMT particles were finely dispersed in the PLLA-co- Bis A ER matrix. The molecular weight kept almost constant at low VMT content (0.5 wt%, 1 wt%) but decreased at higher VMT content (2%). The detailed thermal property and crystallization behavior of samples were studied by using polarized optical microscopy (POM), differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA). The results indicated that the thermal stability, overall crystallization rate and spherulitic texture of PLLA-co-bis A ER were strongly influenced in the presence of vermiculite particles.