The aim of this contribution was to study the rubber elasticity of dry and swollen networks obtained by cyclotrimerization crosslinking reaction of isocyanate groups located at a linear telechelic network precursor. Telechelic diisocyanates were prepared in the undiluted state from 2,4-tolylene diisocyanate, α,ω,dihydroxypoly(oxypropylenes) and different contents of the monool component 2-(2-metoxyetoxy) ethanol. The network synthesis proceeded in a bulk. Detailed network topology was calculated by the theory of branching processes. The equilibrium swelling degree of prepared samples was related to the parameters, which are experimentally accessible for a network arising from an end-linking process using the Flory-Rehner theory. The experimental data for network modulus were compared with those arising from the "affine" model, "phantom’ model" and the model of constrained junctions.