Polymer with functional furan groups

Diels-Alder reactions have been used to synthesize and functionalize polymers, as reported by several groups. Rotello and coworkers112, for example, covalently attached [60]fullerene to furan and cyclopentadiene substituted resins. The reaction with the furan substituted resin proved reversible. The resin was recovered by heating the fullerene functionalized resin. 

Functionalization of polymer chains with the chemical groups (furan and maleimide) is a convenient approach to prepare DA-adduct based crosslinked networks. Furan- (PA-F) and maleimide- (PA-Ml) modified polyamides have been prepared for the constmction of crosslinked polyamides (Fig. 12)... 

If on the other hand the polymerization of a furan derivative takes place through a substituent containing an adequate functionality, such as C=C or C=0, the furan ring should in principle conserve its structure and the polymers obtained will bear it as a side group. It has been found, however, that in some of these systems the normal propagation is accompanied by other reactions which involve participation of the ring and which therefore alter the normal structure of the macromolecule. The second section of this chapter deals with monomers, such as 2-vinylfuran and 2-furaldehyde, which exhibit this general behaviour. 

The same group also reported on the synthesis of multiarm star block copolymers by using Diels-Alder cycloaddition reactions (Dag et al., 2009). First, an a-anthracene-end functionalized PS (PS-anthr) and furan-protected maleimide-end-functionaUzed polymers, including PMMA and PtBuA, were prepared via ATRP. The maleimide functionalities were protected as they can contribute to the copolymerization with MMA or tBuA. Moreover, the polymerization temperature was kept below 60 °C to prevent deprotection during the polymerization. In the next step, a 33-arm anthracene-end functionalized (PS) star polymer was obtained using PS-anthr as macroinitiator and divinyl benzene as crosslinker. These star polymers were then reacted with the unprotected maleimide end-functionalized PMMA or PtBuA to give multiarm star block copolymers via Diels-Alder click reaction. The efficiencies were foimd to be 96 and 88%, respectively. 

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