Mechanical and thermal properties of rice Straw/PLA modified by nano Attapulgite/PLA interfacial layer

A series of attapulgite (ATP) solutions were used for the modification of rice straw (RS) to improve its compatibility with polylactic acid (PLA) matrix through attaching ATP nanorods on the surface of the RS. The reinforcing efficiency of the ATP treatment was evaluated through preparation of PLA composites with the modified rice straw (MRS) by a twin-screw extruder. The obtained MRS/PLA composites exhibited higher tensile strength and modulus than RS/PLA composites due to the enhanced interfacial adhesion between RS and PLA matrix; 18.6% increase in tensile strength was observed for the MRS/PLA composites treated with 2 wt% ATP concentration. SEM images of the tensile fractured surface confirmed that the improved interfacial adhesion was caused by the newly formed PLA-ATP interlayer. The MRS/PLA composites had a higher thermal stability than RS/PLA composites resulting from the heat barrier effect of ATP.