Mechanical properties of PLA/PBS foamed composites reinforced by organophilic montmorillonite

Porous materials have specific properties, such as high surface area, high permeability, lightweight, and low thermal conductivity. In foaming process of thermoplastics, high melt viscosity is indispensable. Neither poly(lactic acid) (PLA) nor poly(butylene succinate) (PBS) has sufficient melt viscosity. In this manuscript, Organophilic montmorillonite (OMMT) was employed to improve the foaming performance PLA/PBS blends. Mechanical tests were undertaken to compare the performance change of PLA/PBS foams before and after reinforcement of OMMT. The compression feature of PLA/PBS foams was discussed. X-ray diffraction (XRD) and scanning electron microscopes were performed to investigate the interaction between OMMT and PLA/PBS foams and the influence of OMMT on cell structure. The results indicated that OMMT can improve the effect of foaming markedly. With 3 wt % OMMT, The compressive strength, flexural strength, and impact strength raised up to 9.2 MPa, 14.0 MPa, and 31.2 kJ/m2, respectively, and the average size of cells changed from 475.6 to 261.4 µm. FT-IR, TGA, and XRD analysis suggested that CTAC has inserted into the Na-MMT platelets and OMMT platelets are more likely to be intercalated or completely separated in PLA/PBS matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40773.