Macromonomers telomerization

Depending on the choice of transfer agent, mono- or di-cnd-functional polymers may be produced. Addition-fragmentation transfer agents such as functional allyl sulfides (Scheme 7.16), benzyl ethers and macromonomers have application in this context (Section 6.2.3).212 216 The synthesis of PEG-block copolymers by making use of PEO functional allyl peroxides (and other transfer agents has been described by Businelli et al. Boutevin et al. have described the telomerization of unsaturated alcohols with mercaptoethanol or dithiols to produce telechelic diols in high yield. 

We will focus on recent developments made on the synthesis of macromonomers through the telomerization process. This may concern the synthe-... 

We realized a similar result with dimethylaminoethyl methacrylate as the monomer. Telomerization was performed with 2-mercaptoethanol in the presence of AIBN. This study represents the first example of telomerization of a monomer with a tertiary amine. We showed that the telomerization of such a monomer was highly dependent on the solvent. Indeed, polar solvents strongly favor the nucleophilic addition of thiol onto the methacrylate double bond [255] (Scheme 51). In a second step, oligomers bearing an alcohol group at the chain end can react with IEM to lead to a macromonomer with a methacrylic function. 

The group of Akashi [257-263] extensively used NIPAM to synthesize macromonomers with a benzyl group. First, the telomerization of NIPAM is realized with 2-mercaptoethanol, followed by etherification of the alcohol group by using chlorostyrene (Scheme 54). 

Similarly, dicarboxylic transfer agents were used in telomerization. For instance, Yamashita [283-288] realized the synthesis of MMA macromonomer by using thiomalic acid as a transfer agent (Scheme 57). 

The telomerization process is certainly an appropriate technique for the synthesis of (meth)acrylic-type macromonomers, but also of (meth)acrylo-nitrile-derived macromonomers. This technique is open to almost all conventional monomers but is also devoted to original monomers such as NIPAM. We can note that macromonomers based on halogenated monomers were synthesized by telomerization, using redox catalysis. 

Like the telomerization process, ATRP enables the synthesis of two different types of macromonomers either with a polymerizable double bond or with a polycondensable group. As depicted in Sect. 3.1 on the design of the macromonomers, the polycondensable groups also comprise groups that afford ring-opening polymerization. 

A methacrylate-type poly(vinylidene fluoride) (PVF2) macromonomer was synthesized from vinylidene fluoride via hydroxy-terminated PVF2 obtained by telomerization of vinylidene fluoride. Although homopolymerization of this macromonomer did not proceed completely, it was successfully copolymerized with MMA. 

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