The critical point theory is generalized to include gelation in multilink system with f functional units and J junction points. The equations derived include, as special cases, the cyclotrimerization model of J = 3, and the R–Af model of J = 2. The theory is applied to the recent observation of the cyclotrimerization of bisphenol‐A dicyanate. The theoretical prediction agrees exactly with the Stutz‐Simak observation, Dc = 0.504, and accords with the Georjon‐Galy‐Pascault observation, giving a confirmation of the physical soundness of the theory. Under the smoothness assumption, we derive post‐gelation relationships with loop formation, the result suggesting the formation of permanent sol molecules that resist being absorbed into gel phase throughout an entire reaction process.