Polymerization by carbonyl substitution reactions

Co-polymerization of pentaerythritol and two other monomers—an unsaturated acid and benzene 1,3-dicarboxylic acid—gives a network of polymer chains branching out from the quaternary carbon atom at the centre of pentaerythritol. The reaction is simply ester formation by a carbonyl substitution reaction at high temperature (> 200°C). Ester formation between acids and alcohols is an equilibrium reaction but at high temperatures water is lost as steam and the equilibrium is driven over to the right. 

The sole study on transition metal carbonyl ion chemistry with ICR mass spectrometry has been published by Forster and Beauchamp 157), The ions produced by electron impact Fe+, Fe(CO)+ and Fe(CO)t in pure Fe(CO) 5, undergo two polymerization reactions to yield Fe CO)t and Fea(CO) 5. In binary mixtures with CHgF, H2O and NH3, substitution reactions occur like ... 

Carbonyl addition-substitution n. Step-growth polymerization schemes based on carbonyl addition-substitution reactions are almost entirely concerned with reaction of aldehydes step-growth polymers prepared by this type of reaction include polyacetals, phenolformaldehyde polymers, ureaformaldehyde polymers, and melami-neformaldehyde polymers. 

Quinolines substituted at the pyridine ring may be obtained by using a substituted a ,/3-unsaturated aldehyde or ketone instead of the glycerol as starting material. However often a large amount of the carbonyl component polymerizes under the reaction conditions. 

Polymerizations of vinyl ketones such as methyl vinyl ketone are also complicated by nucleophilic attack of the initiator and propagating carbanion at the carbonyl group although few details have been established [Dotcheva and Tsvetanov, 1985 Hrdlovic et al., 1979 Nasrallah and Baylouzian, 1977]. Nucleophilic attack in these polymers results in addition, while that at the ester carbonyl of acrylates and methacrylates yields substitution. The major side reaction is an intramolecular aldol-type condensation. Abstraction of an a-hydrogen from a methyl group of the polymer by either initiator or propagating carbanion yields an a-carbanion that attacks the carbonyl group of the adjacent repeat unit. 

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