  Let $G=(V,E)$ be a finite simple graph. The Sombor index $SO(G)$ of $G$ is
defined as $\sum_{uv\in E(G)}\sqrt{d_u^2+d_v^2}$, where $d_u$ is the degree of
vertex $u$ in $G$. Let $G$ be a connected graph constructed from pairwise
disjoint connected graphs $G_1,\ldots ,G_k$ by selecting a vertex of $G_1$, a
vertex of $G_2$, and identifying these two vertices. Then continue in this
manner inductively. We say that $G$ is a polymer graph, obtained by
point-attaching from monomer units $G_1,...,G_k$. In this paper, we consider
some particular cases of these graphs that are of importance in chemistry and
study their Sombor index.
