What is the structure of repeating units in PVC and PAN?

Polyvinyl chloride (PVC) consists of repeating units of vinyl chloride monomers, characterized by the structure -[CH2-CHCl]n-, where "n" indicates the number of repeating units. Polyacrylonitrile (PAN), on the other hand, is composed of repeating units of acrylonitrile, represented as -[CH2-CH(CN)]n-. Both polymers exhibit distinctive properties due to the functional groups present in their repeating units.