Answer:
a) Polymerization reaction by addition
In this polymerization, there is always the breakage of a pi bond in the monomer, which causes two free valences to appear in the structure, such as in the formation of polyethylene, a polymer widely used in pharmaceutical packaging.
Step-by-step explanation:
Structural formula of polyethylene addition polymer
In the polymerization of polyethylene, molecules of ethylene (ethene) are used as monomer, which has a pi bond between the two carbon atoms. When this bond is broken, two free valences arise, one in each carbon atom that was involved in the pi bond. The monomers unite exactly in each of these valences, that is, the valence of one binds to the valence of the other, and so on.
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