Toxicants organometallic polymers

For instance, in the last decade synthesis of poly(ester-alt-ether) was intensively studied. A common enzyme used in these syntheses is CALB. Polymerization of l,5-dioxepan-2-one (DXO) was performed by enzyme-catalyzed ROP in order to avoid contamination of product polymers by toxic organometallic catalysts [92], High molecular weight of poly(DXO) was obtained (Mn = 56000 Mw = 112000, 97% yield) at 60 °C for 4h. The polymerization had the characteristics of a living polymerization, as indicated by the linearity of plots between M and monomer conversion, meaning that the product molecular weight could be controlled by the stoichiometry of the reactants. Similarly, Nishida et al. [91] carried out enzymatic ROP of l,4-dioxan-2-one at 60 °C catalyzed by Novozym 435 that resulted in a polymer with Mw = 41000 in 77% yield. 

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