Living anionic PDMS terminated with

Termination of living anionic propagating chains with suitable TEMPO compounds followed by NMRP has been employed for the preparation of several other block copolymers including PBd- J-PSt/ " " PDMS-[ -PSt/ PEO-b-PSt/ and PEO-b-P4VP. ... 

Star polymers exhibiting three different branches (PS, PDMS, and poly( er -butyl methacrylate) were prepared in a similar way, the first being the preparation of PDMS macromonomers containing a terminal nonpolymeriz-able DPE entity. Thus, a living PS is reacted with the PDMS macromonomers to create active sites on DPE. These sites served subsequently as initiators for the anionic polymerization of tert- mXy methacrylate [89]. Stadler and coworkers have used that reaction to generate polystyrene-arm-polybutadiene-arm-poly(methyl methacrylate) [90]. 

An alternate way to make block copolymers involving PDMS blocks 124,125) is to have these chains fitted with epoxide functions at chain end, and to react them with a vinylic or dienic polymer carrying terminal COOH functions. Sequential addition of monomers has also been used, the ring opening polymerization of the cyclic trimer (D3) being initiated by the anionic site of a living polymer126). 

For the PDMS-grafted systems a somewhat different method was used since PDMS is not soluble in DMF. An anionic polymerisation method was again used to produce "living" PDMS chains, but in this case these were reacted with acetic acid to give hydroxyl-terminated chains. The silica particle dispersions in ethanol were stable, and remained stable on adding n-heptane to give a 1 1 (by volume) solvent mixture in which PDMS is still soluble. 

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