CBSE Class 12-science Answered
Differences between chain growth and step growth polymerisation:
Chain growth polymerisation |
Step growth polymerisation |
*Concentration of monomers disappears early in the reaction. |
* Concentration of monomers decreases steadily throughout the reaction |
*Reaction is fast and polymer is formed at once. |
*The polymer is formed in gradual steps. |
*There is very little change in the molecular mass throughout the reaction. |
*The molecular mass of polymer increases throughout the reaction. |
*Increase in reaction time increases the yield but molecular weight is affected a little. |
*Long reaction time is required to get high molecular mass polymer. |
*Only one repeating unit is added at a time. |
Any two species present can react. |
*Reaction mixture contains only a monomer, polymer and growing chain. |
*All molecular species are present at any stage. |
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