Processability of microcellular PLA has been an important field of study considering its different applications. Development of open cell morphology in PLA foaming is an challenging issue towards some special applications like scaffold, filtration membrane and packaging application. The current study is focused on the development of microcellular PLA by using solid-state batch foaming process. Solid-state batch foaming process was carried out by two different techniques: thermal induced gas phase separation and ultrasonic induced gas phase separation process. Foam morphology was characterized by scanning electron microscope and evaluated by ImageJ software inorder to identify the type of cell nucleation and efficiency of cell opening during the foaming process. The present study comprises of preparing the plasticized PLA based nanocomposites (P-PLANCs) by using organically modified layered silicates (organoclay) as nanofiller, polyethylene glycol (PEG) as plasticizer and subsequent batch foaming of P-PLANCs samples. During foaming, nanoclay acts as nucleating filler aswellas diffusion barriers increasing the foaming time. Nanoclay simultaneously increases the cell density and individual cell expansion leads to a hexagonal cellular morphology. The injection-molded plasticized PLA nanocomposites were gas saturated by using supercritical CO2 under a gas pressure of 50bar at 30°C. Solid-state batch foaming was performed for the gas saturated samples in hot glycerin bath as well as in an ultrasonication water bath. The CO2 gas absorption of the samples was measured for 30hrs in 50bar pressure at 30°C temperature. CO2 induced foam crystallization were studied by XRD analysis of respective-foamed samples. XRD pattern of foamed samples reveal simultaneous clay expansion by the infusion of CO2 gas into the clay gallery. Toughening effect of high temperature foamed samples was studied from increasing impact strength of foamed samples.