Abstract
During molding process the rheological behavior of phenolic molding compound becomes unsteady and very complicated according to the chemical reaction.
Then, for the purpose of clarification of the early flow properties during molding process, we used some grades of reacting materials which were made by hot-pressing the model phenolic molding compound at various molding-time.
About the flow test, we used capillary-flow method from necessity of the informations on the flow behavior in high shearing rate region.
The results of the above flow test were as follows;
1) Early flow behavior of phenolic molding compound can be treated approximately with pure viscous flow and follows the Ostwald-de Waele (Power law) model.
2) According to the reaction proceeding, the viscosity of the material increases and non-Newtonian behavior becomes remarkable.
The change of two-parameters in the power law equation (m and n) follows apparently first-order reaction model, (referred Fig. 3 and Fig. 6), that is;
mt-mo/mo=10.9 [1-exp (-kt)]
no-nt=0.13 [1-exp (-kt)]
Measurements were made on the flow properties ranging in molding temperature from 130°C to 160°C, and ranging in molding time from 0 sec to 50 sec.
