I'm just wondering, what gives polyethylene its property chemical resistance? Does it have something to do with the electronegativies between the C-H bonds and most chemicals are unable to break the bonds between C-H, therefore unlikely to take part in a chemical reaction? Thank you Edit: I think I'm asking too much questions... hmm but how does chlorine atoms in PVC polymer prevents fire? And also how does the bonding make it water resistant??? This is like a research task and I couldn't think why these properties can be related in terms of bonding :( Thank you so much!