gel point

also contains definition of: gelation point
https://doi.org/10.1351/goldbook.GT07535
Point of incipient network formation in a process forming a chemical or physical polymer network.
Notes:
  1. In both network-forming polymerization and the crosslinking of polymer chains, the gel point is expressed as an extent of chemical reaction (c.f., gel time).
  2. At the gel point a solid (network) material spanning the entire system is formed.
  3. The gel point is often detected using rheological methods. Different methods can give different gel points because viscosity is tending to infinity at the gel point and a unique value cannot be measured directly.
See also: gel fraction
Source:
PAC, 2007, 79, 1801. (Definitions of terms relating to the structure and processing of sols, gels, networks, and inorganic-organic hybrid materials (IUPAC Recommendations 2007)) on page 1809 [Terms] [Paper]