Let $\hat{ \frak g}$ be an untwisted affine Kac-Moody algebra. The quantum group $U_h(\hat{ \frak g})$ (over $\mathbb{ C}[[h]]$) is known to be a quasitriangular Hopf algebra: in particular, it has a universal $ R $--matrix, which yields an $ R $--matrix for each pair of representations of $U_h(\hat{ \frak g})$. On the other hand, the quantum group $U_q(\hat{ \frak g})$ (over $\mathbb{ C}(q) $) also has an $ R $--matrix for each pair of representations, but it has not a universal $ R $--matrix so that one cannot say that it is quasitriangular. Following Reshetikin, one introduces the (weaker) notion of braided Hopf algebra: then $ U_q(\hat{ \frak g})$ is a braided Hopf algebra. In this work we prove that also the unrestricted specializations of $U_q(\hat{ \frak g})$ at roots of 1 are braided: in particular, specializing $q$ at 1 we have that the function algebra $F \big[ \hat{ H} \big]$ of the Poisson proalgebraic group $\hat{ H}$ dual of $\hat{ G}$ (a Kac-Moody group with Lie algebra $\hat{ \frak g} \,$) is braided. This is useful because, despite these specialized quantum groups are not quasitriangular, the braiding is enough for applications, mainly for producing knot invariants. As an example, the action of the $ R $--matrix on (tensor products of) Verma modules can be specialized at odd roots of 1.
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