How do you terminate the process of addition polymerization?

Answer 1

You add a chain terminator to the original polymerization mixture. For example, suppose that a polymer chain is growing through free radical polymerization. You add something like CCl4. The -CH2CH2* abstracts Cl from CCl4 and ends in -CH2CH2Cl.

Answer 2

LOL. Simple.

You run out of reactants.