Ethylene oxide ring opening polymerisation

One variation of rearrangement polymerisation is ring-opening polymerisation. Important examples include the polymerisation of trioxane, ethylene oxide and e-caprolactam Figure 2.8 (a) to (c) respectively). It is to be noted that... 

Coordination polymerisation was first proposed in 1956 for the unusual, at that time, low-pressure polymerisation of ethylene and polymerisation of propylene with the transition metal catalysts discovered by Ziegler in 1953 [1], and for the ferric chloride catalysed ring-opening polymerisation of propylene oxide to crystalline polymer reported by Pruitt et al. in a Dow patent [2]. 

A methoxy-terminated PEG-/>-PLA copolymer (CHsO-PEG-fo-PLA) was synthesised using the anionic ring-opening polymerisation (ROP) of both ethylene oxide and D,L-lactide in anhydrous tetrahydrofuran (THE). A typical experimental procedure for the synthesis of CHsO-PEG-f -PLA is described below. 

Zhao Y, Tmhlar DG (2007) How well can new-generation density functionals describe protonated epoxides where older functionals feil J Org Chem 72(1 ) 295-298 earlier PR, Deora N, Crawford TD (2006) Protonated 2-methyl-1,2-epoxypropane a challenging problem for density functional theory. J Org Chem 71(4) 1592-1597 Frenking G, Kato H, Fukui K (1975) An MO-theoretical treatment of the cationic ring-opening polymerisation. I. Ethylene oxide. Bull Chem Soc 45(1) 6-12... 

Polyethers, which contain oxygen as well as carbon atoms in their backbones, are examples of addition polymers that are generally made by a ring-opening reaction. Thus the cyclic compound ethylene oxide polymerises to a polyether as follows ... 

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