Which of the following is (are)repeating unit(s)of step-growth polymers?
A)Only I
B)Only II
C)Only III
D)I and II

Question

Which of the following is (are)repeating unit(s)of step-growth polymers? 
A)Only I 
B)Only II 
C)Only III 
D)I and II

Quizplus · Accepted Answer

Step-growth polymers are formed by the reaction of two or more types of monomers, with each monomer typically containing two or more reactive functional groups. As a result, the repeating unit of a step-growth polymer can be quite complex, and may not be easily identifiable. However, in some cases, certain structural units may repeat throughout the polymer chain, and these can be considered the repeating units. Option I and II both show possible repeating units in step-growth polymers, while option III does not. Therefore, the best choice is D, as both I and II show repeating units in step-growth polymers.

Which of the Following Is (Are)repeating Unit(s)of Step-Growth Polymers