Plastic grinder

The utility model discloses a plastic grinder. The plastic grinder comprises a grinding cylinder, wherein a feeding opening and a discharging opening are respectively formed in two ends of the grinding cylinder; a grinding roller body is arranged in the grinding cylinder; the grinding cylinder comprises an inner cylinder and an outer cylinder; a sealed hollow layer is arranged between the inner cylinder and the outer cylinder; a cooling pipe is arranged in the hollow layer; the cooling pipe is spirally arranged along the inner wall of the outer cylinder in a manner of screwing from the bottom of the grinding cylinder; a water inlet and a water outlet are respectively formed in two ends of the cooling pipe; the water inlet and the water outlet extend to the outside of the grinding cylinder. The plastic grinder disclosed by the utility model is capable of dissipating heat of the grinding cylinder out in time and preventing the material from softening in the heat, sticking to other parts and causing extreme damage, so that the working quality of the grinder is relatively high.