Initiators of grafting reactions

For selectiveness of initiation of graft reactions, the use of a tin octoate (SnOct2) (or tin(II) 2-ethylhexanoate) catalyst is convenient for preparing this type of copolymers, polysaccharide-gra/f-PHAs, because the ring-opening polymerization of cyclic esters such as lactides and e-caprolactone (CL) can be initiated efficiently by hydroxo-initiators (i.e. based on hydroxyl groups) in the presence of SnOct2 [12-16], as exemplified in Scheme la. 

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