1. See the color. The color of whole rolls is yellow, then it is PVC material ,white is for PE.

2. Hands rubbing. PE cling films viscosity is poorer, after rub your hands it is easy to open. For PVC cling film,it is not easy to open after rubbing with hands. 

3. To burn it. When  fire ,PE cling film can burn easily, keep off the fire it will not die out.

For PVC cling film,fire will die out in this situation. What''s more, there will be unpleasant smell.