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Chemistry · Glossary

What is Living polymerisation?

Definition 29.13 University Chemistry — Year 2 · Chapter 29 — Polymers: Synthesis, Structure and Properties

A living polymerisation is a chain-growth polymerisation without termination or transfer: all chains start together and keep growing as long as monomer remains, and they resume when more monomer is added. The anionic polymerisation of styrene initiated by butyllithium in a dry, aprotic solvent is the classic example.

Two samples with the same X_n = 50 (models). Living chains crowd around 50 (1.02); step-growth chains spread from monomer to several hundred units (1.98).
Two samples with the same Xˉn=50\bar X_n = 50 (models). Living chains crowd around 50 (Đ≈1.02\text{\DH} \approx 1.02); step-growth chains spread from monomer to several hundred units (Đ≈1.98\text{\DH} \approx 1.98).
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