Terminations in Coordination Polymerizations

The terminations usually occur by chain transferring, either by an internal hydride transfer [261]  

Terminal unsaturation in the products was confirmed by infrared spectroscopy. Hydrogen terminates the reactions and it is often added to control the molecular weights of the products. Protonic acids do the same thing  

---

The understading and control of termination in coordination polymerizations would represent an important technological advance. The productivity of catalysts would be enhanced [as expressed by the ratio of polymer mass (kg) produced per 1 kg of transition metal, or sometimes per 1 kg of catalyst] and the content of dangerous catalyst residues in the product would be reduced. 

---