We studied the influence of the share of catalysts and heating rate on the curing process of an adhesive, specifically the gelling point and elastic shear modulus G'. Synthetic polymeric condensation adhesive Urea-formaldehyde (UF)-type Prefere 10F102 with physical and chemical way of curing was used. Measurements were performed with rheometer having 2 parallel plates and also by differential scanning calorimetrics (DSC). The purpose of the testing was to search possible correlations between the results of both methods. We used heating rate of 5, 10 and 20 K/min and fixtures shares of 0.5 %, 1 %, 2 % and 3 % with the rheometer. As a fixture agent we used 25 % aqueous solution of ammonium sulphate. The temperature rate testing with rheometer was from 30 up to 95 °C, we used temperature rate from 30 to 100 °C for DSC. To determine the gelling point we took the intersection of the elastic shear modulus G' and the viscosity shear modulus Gʼʼ. We found that by increasing the both, the concentration of fixtures and heating rate, diminishes the temperature and speeds the time of gelling point. We have shown that the final value of the module G' are about the same, regardless the amount of catalyst or heating rate. Using the DSC "Module Free kinetics" we simulated and determined the necessary time and temperature needed to achieve a certain level of hardness.
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