Do microfilaments have polarity?

Yes, microfilaments have polarity. Microfilaments are solid rods composed of a protein called actin. When actin subunits come together to form microfilaments, they interact directionally. All are connected in such a way that they all have the same orientation, where the top of one subunit always interacts with the bottom of another. This results in the two ends of the microfilament being distinctly different. Hence it exhibits polarity. However, this is only in the sense of having directionality. It is not related in any way to electrical charge.