Chapter 22, Problem 20TE

To determine

The reason of Plastic food wrap being stickier than polyethylene.

Answer to Problem 20TE

Plastic food wrap is a stickier plastic than polyethylene because plastic food wraps are made up of a polymer known as polyvinylidene chloride. Due to presence of large chlorine atoms they become sticky.

Explanation of Solution

Food wraps are made up of an addition polymer named polyvinylidene chloride. Its trade name is Saran. This polymer contains chlorine atoms. Due to presence of large atom of chlorine it becomes sticky. But there is no chlorine atom in polyethylene. So, it is not sticky.Polyvinylidene Chloride is synthesized from ethylene dichloride. It is first developed by DOW Chemicals in 1939.It has a great resistance againstwater, oxygen. It readily changes to hydrogen chloride above $\text{125}{}^{\text{o}}\text{C}$ .

Conclusion:

Therefore, due to presence of large chlorine atom the food wrap plastics are sticky in nature.