PU is the adhesive system of protective film (acrylic is common), while PE refers to the category of protective film substrate. PE, the simplest polymer organic compound, is the most widely used polymer material in the world today. PE protective film is made of special polyethylene (PE) plastic film, which is divided into high density polyethylene protective film, medium density polyethylene and low density polyethylene according to its density. PU Chinese name is polyurethane, PU is polyurethane, PU film is polyurethane film, is a non-toxic and harmless environmental protection materials, no harm to human skin, and widely used in clothing fabrics, medical and health, leather and other fields.

I don't know what PU film is, but what PE film is.