Gel time was determined using the cup test method, following the guidelines of ASTM D2471 and CIRIA C774. Tests were initiated between 20 and 45 minutes after mixing, depending on the formulation evaluated, and continued until the complete transition of the system from the liquid state to the gelled state. The gelation criterion was established based on visual and tactile assessment, in accordance with standardized procedures. • Thermal control The temperature of the components (base resin, activators, retarders, and saline solutions, as applicable) was measured prior to mixing using calibrated digital thermometers. Ambient temperature was also recorded during test execution. In all cases, it was verified that material temperatures remained below 32 °C, the limit established to prevent uncontrolled acceleration of the chemical reaction. • Repeatability and traceability All tests were conducted under controlled laboratory conditions, using calibrated equipment and documented procedures. Independent replicates were performed for each formulation, allowing evaluation of result consistency and ensuring the reliability of the experimental data. 5. RESULTS AND DISCUSSION 5.1 Influence of Temperature on System Preparation Tables 3 to 8 present the temperatures measured for the individual components and the ambient conditions during the preparation of the different systems evaluated: acrylamide, acrylates, and colloidal silica. In all tests performed, the recorded temperatures remained below 32 °C, both for the materials and the ambient temperature. This controlled thermal range is critical, considering that the polymeric systems evaluated gel through free-radical polymerization reactions, which are highly sensitive to temperature. Table 3 – Temperature records of components used in the preparation of the acrylamide-based system Test Desig n No. Acrylamide-based system Temperature (°C) Base Water TEA Retarder Persulfat e Ambien t Test 1 1 22.1 23.1 25.1 21.6 22.1 25.4 Test 2 1 22.4 23.2 25.2 21.5 22.3 25.9 Test 3 2 23.0 23.5 25.7 21.6 22.4 28.1 Test 4 2 23.4 23.6 25.4 21.6 22.7 28.1 Table 4 – Temperature records of components used in the preparation of acrylate system A Test Acrylate system A
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