Flowing enhancer, aka internal lubricant, can improve the flowing behavior and processability of plastics. Ionic liquid flowing enhancers can significantly improve the flowing behaviors of plastics when the plastics are hot melted and processed. Different from traditional flow enhancers, ionic liquid flowing enhancers will not affect the thermal, mechanical properties of the plastics when the plastics cool down to room temperature. This is because of a brand-new mechanism of "reversible plasticizer enhancing flowing behaviors".