The objective of this work was to explore the potentials of porous and electrically conductive activated carbon particles for possible enhancement of multifunctional properties of PLA. The activated carbon was inexpensively prepared from acrylic fibrous wastes by novel single stage carbonization and physical activation. The influence of 800°C, 1,000°C, and 1,200°C carbonization temperature on physical, morphological, and electrical properties was studied from EDX, X‐ray diffraction, SEM, and BET analysis. Later, the carbonized acrylic fibrous waste was pulverized in dry conditions by high energy planetary ball milling to get activated carbon particles. The particles were then incorporated into PLA under 1, 5 and 10 wt% loading to prepare composite films by solvent casting, and their electrical conductivity, EMI shielding, thermo‐mechanical, and thermal stability properties were investigated. POLYM. COMPOS., 40:578–590, 2019. © 2017 Society of Plastics Engineers