Macromonomers with a Polymerizable Double Bond

The characteristics, i.e., functionality, Mn, and conversion, of VAc macromonomers are given in Table 23. 

To allow the further copolymerization of this macromonomer with other monomers, the chain-end iodine is extracted by nucleophilic substitution with sodium azide (NaN3). 

The amine functionality of the polymers was studied versus the molar mass and it is shown to decrease when the molar mass increases (Fig. 3). 

Owing to their isocyanate group, IEM and l-(isopropenylphenyl)-l,l-di-methylmethyl isocyanate (TMI) have been extensively used to achieve a macromonomer structure. 

The macromonomers were then copolymerized with styrene in ethanol. The resulting microspheres, with a PS core and poly(NIPAM) brushes, were thermosensitive [264-267]. 

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Our team also realized the synthesis of macromonomers with a polymerizable double bond by using peculiar transfer agents. For instance, telomeriza-tions of (meth)acrylates were performed in the presence of cysteamine, i.e., thiol with an amine group, leading to PMMAs with an amine at the chain end [253]. However, amines enable the Michael addition onto the double bond activated by the carbonyl group. Hence, before performing the telom-erization, the amine group is protected (chlorhydrate salt) and recovered by a simple basification of the solution (Scheme 48). 

Synthesis of Macromonomers with a Polymerizable Double Bond... 

Scheme 64 Different routes to obtain macromonomers with a polymerizable double bond 3.4.1.1...

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. 

All these cationic deactivation processes were performed with oxolane as the monomer and with various initiators such as triethyloxonium tetrafluoroborate and benzoyl, acetyl or propionyl hexafluoroantimonate. Efficient difunctional cationic initiators such as adipoyl- or terephthaloyl hexafluoroantimonate) can also be used 42 to synthesize bifunctional macromonomers containing at both chain ends a polymerizable double bond. 

The polymerizable double bond may be obtained by functionalizing the amine with a monomer such as methacrylate glycidyl ether or isocyanoethyl methacrylate (IEM), i.e., reaction of amine with an epoxy or isocyanate group. We chose to functionalize the amine by using maleic anhydride to get highly stable (thermally) maleimide macromonomers [162], as shown in Scheme 49. 

End-functionalized polymers with polymerizable groups such as double bonds and heterocycles of course provide macromonomers allyl, vinyl ester, vinyl ether, lactone, and epoxy are examples of such a category whose a-ends are not susceptible or have little susceptibility to metal-catalyzed radical polymerization. As discussed above, for example, allyl chloride and bromide (FI-33 and FI-34) are effective initiators to be used for styrene with CuCl and CuBr catalysts,161 while allyl compounds with remote halogens such as FI-35 and FI-36 allow the polymerization of methacrylates with high initiation effi-... 

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