Starting Monomers Cyclic Ketene Acetals

2-methylene-l,3-dioxepane. Till date, synthetic recipes for making a large number of structurally different CKAs are available (Chart 2.1) and they are stable for a longtime if protected from moisture and air [12,14, 15]. 

9-Disubstituted-4-methylene- 2-Methylene-1,3,6- 2,5-Methylene -1,3- 2-Ethyl ldene-4-methyl/ethyl- 

Perfluoro-2-methylene- 2-Difluoromethylene- Petfluoro-2-methylene-4-methyl- 2-Dlfluoromethylene-  

Chart 2.1 A wide variety of cyclic ketene acetals are available in the literature undergoing radical ring-opening polymerization for the formation of polyesters. CKAs studied in details in literature are presented here with their names and structures [12]. 

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